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  • Inorganic Chemistry  (5,042)
  • Fluid Mechanics and Thermodynamics
  • 1985-1989  (3,444)
  • 1950-1954  (1,657)
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  • 1
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    An Experimental Investigation of Shear Layer Mixing in Supersonic Flows (1988)
    In:  Other Sources
    Details
    Publication Date: 2011-08-26
    Description: In the design of a combustor, information is necessary for the mixing of the fuel and air in order to determine the optimum combustor length. In scramjet combustors the mixing often takes place in a shear layer that is formed between the fuel and air. This research was an experimental study of shear layers in supersonic flows aimed at determining what mechanisms affect the shear layer so that the mixing could be better predicted. A second goal was to provide sufficient instream information for use in checking existing Computational Fluid Dynamic (CFD) codes. The shear layer between a supersonic two-dimensional air stream (M = 2 or M = 3) was mixed with a near sonic two-dimensional air stream (M = 1.2). Instream measurements of pitot pressure and cone static pressure were used to determine mean velocity profiles at various axial locations. These velocity profiles were used to determine the shear layer spreading rate and are compared with various predictions. Wall measurements of static pressure, temperature and skin friction were also taken and are presented. The instream measurements were also used for comparison with an existing CFD code. The upstream velocity, pressure and temperature profiles were used as a starting profile and the code was used to calculate downstream profiles for comparison with the experimental results. Reasonable agreement between the measured and calculated results was obtained.
    Keywords: Fluid Mechanics and Thermodynamics
    Type: CN-164-463
    Format: text
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  • 2
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    Second-Order Modeling of Low-Reynolds-Number Turbulence Near Walls (1989)
    In:  CASI
    Details
    Publication Date: 2004-12-03
    Description: This paper presents a set of second-order closure models for low-Reynolds-number turbulence near the wall. Existing closure models for the Reynolds-stress equations were modified to show proper near-wall behavior. A dissipation-rate equation for the turbulent kinetic energy is also reformulated. The proposed models satisfy realizability and will not produce unphysical behavior. Fully developed channel flows are used for model testing. The equations are solved for the mean velocity, the Reynolds stresses, and the dissipation rate of the turbulent kinetic energy. The calculations are compared with both direct numerical simulations and with measurements. It is shown that the present models perform well in predicting the behavior of the turbulence near a wall. Significant improvements over previous models in predicting the components of the Reynolds stress tensor are obtained in the present models.
    Keywords: Fluid Mechanics and Thermodynamics
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  • 3
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    Water Jetting (1985)
    In:  CASI
    Details
    Publication Date: 2018-06-09
    Description: Hi-Tech Inc., a company which manufactures water jetting equipment, needed a high pressure rotating swivel, but found that available hardware for the system was unsatisfactory. They were assisted by Marshall, which had developed water jetting technology to clean the Space Shuttles. The result was a completely automatic water jetting system which cuts rock and granite and removes concrete. Labor costs have been reduced; dust is suppressed and production has been increased.
    Keywords: Fluid Mechanics and Thermodynamics
    Type: Spinoff 1985; 85
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  • 4
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    Riblets for Stars and Stripes (1987)
    In:  CASI
    Details
    Publication Date: 2018-06-09
    Description: Stars and Stripes racing yacht brought the American's Cup back to the United States. Originating from NASA's drag reduction technology, the boats "secret weapon" was that the hull's underside was coated with riblets. Riblets are small, barely visible grooves on the surface of an airplane intended to reduce skin friction by smoothing the turbulent airflow next to the skin. Grooves are V-shaped with the angle pointing in the direction of the airflow. No deeper than a scratch, they have a pronounced beneficial influence on air turbulence. *No longer commercially available.
    Keywords: Fluid Mechanics and Thermodynamics
    Type: Spinoff 1987; 66-67
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  • 5
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    Flow Measurement (1988)
    In:  CASI
    Details
    Publication Date: 2018-06-09
    Description: Macrodyne, Inc.'s laser velocimeter (LV) is a system used in wind tunnel testing of aircraft, missiles and spacecraft employing electro optical techniques to probe the flow field as the tunnel blows air over a model of flight vehicle and to determine velocity of air and its direction at many points around the model. However, current state-of-the-art minicomputers cannot handle the massive flow of real time data from several sources simultaneously. Langley developed instrument Laser Velocimeter Autocovariance Buffer Interface (LVABI). LVABI is interconnecting instrument between LV and computer. It acquires data from as many as six LV channels at high real time data rates, stores it in memory and sends it to computer on command. LVABI has application in variety of research, industrial and defense functions requiring precise flow measurement.
    Keywords: Fluid Mechanics and Thermodynamics
    Type: Spinoff 1988; 87
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  • 6
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    Calculations of Laminar Heat Transfer Around Cylinders of Arbitrary Cross Section and Transpiration-Cooled Walls with Application to Turbine Blade Cooling (1951)
    In:  CASI
    Details
    Publication Date: 2019-06-28
    Description: An approximate method for development of flow and thermal boundary layers in laminar regime on cylinders with arbitrary cross section and transpiration-cooled walls is obtained by use of Karman's integrated momentum equation and an analogous heat-flow equation. Incompressible flow with constant property values throughout boundary layer is assumed. Shape parameters for approximated velocity and temperature profiles and functions necessary for solution of boundary-layer equations are presented as charts, reducing calculations to a minimum. The method is applied to determine local heat-transfer coefficients and surface temperature-cooled turbine blades for a given flow rate. Coolant flow distributions necessary for maintaining uniform blade temperatures are also determined.
    Keywords: Fluid Mechanics and Thermodynamics
    Type: NACA-RM-E51F22
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  • 7
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    Impingement of Water Droplets on an Ellipsoid with Fineness Ration 10 in Axisymmetric Flow (1954)
    In:  CASI
    Details
    Publication Date: 2019-06-28
    Description: The presence of radomes and instruments that are sensitive to water films or ice formations in the nose section of all-weather aircraft and missiles necessitates a knowledge of the droplet impingement characteristics of bodies of revolution. Because it is possible to approximate many of these bodies with an ellipsoid of revolution, droplet trajectories about an ellipsoid of revolution with a fineness ratio of 10 were computed for incompressible axisymmetric air flow. From the computed droplet trajectories, the following impingement characteristics of the ellipsoid surface were obtained and are presented in terms of dimensionless parameters: (1) total rate of water impingement, (2) extent of droplet impingement zone, and (3) local rate of water impingement. These impingement characteristics are compared briefly with those previously reported for an ellipsoid of revolution with a fineness ratio of 5.
    Keywords: Fluid Mechanics and Thermodynamics
    Type: NACA-TN-3147
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  • 8
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    Investigation of the Jet Effects on a Flat Surface Downstream of the Exit of a Simulated Turbojet Nacelle at a Free-Stream Mach Number of 2.02 (1954)
    In:  CASI
    Details
    Publication Date: 2019-06-28
    Description: An investigation at a free-stream Mach number of 2.02 was made to determine the effects of a propulsive jet on a wing surface located in the vicinity of a choked convergent nozzle. Static-pressure surveys were made on a flat surface that was located in the vicinity of the propulsive jet. The nozzle was operated over a range of exit pressure ratios at different fixed vertical distances from the flat surface. Within the scope of this investigation, it was found that shock waves, formed in the external flow because of the presence of the propulsive jet, impinged on the flat surface and greatly altered the pressure distribution. An integration of this pressure distribution, with the location of the propulsive jet exit varied from 1.450 propulsive-jet exit diameters to 3.392 propulsive-jet exit diameters below the wing, resulted in an incremental lift for all jet locations that was equal to the gross thrust at an exit pressure ratio of 2.86. This incremental lift increased with increase in exit pressure ratio, but not so rapidly as the thrust increased, and was approximately constant at any given exit pressure ratio.
    Keywords: Fluid Mechanics and Thermodynamics
    Type: NACA-RM-L54E05a
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  • 9
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    Approximate Turbulent Boundary-Layer Development in Plane Compressible Flow Along Thermally Insulated Surfaces with Application to Supersonic-Tunnel Contour Correction (1950)
    In:  CASI
    Details
    Publication Date: 2019-06-28
    Description: Numerical solutions of the differential equation obtained from the momentum theorem for the development of a turbulent boundary layer along a thermally insulated surface in two-dimensional and in radial shock-free flow are presented in tabular form for a range of Mach numbers from 0.100 to 10. The solution can be used in a step-wise procedure with any given distribution of favorable pressure gradients and for zero pressure gradients. Solutions are also given for use with moderate adverse pressure gradients. The mean velocity in the boundary layer is approximated by a power-law profile. In view of the stepwise integration methods to be used, the exponent designated the profile shape can be varied along the surface between the integral fraction limits 1/5 and 1/11 through interpolation. Agreement obtained between theoretical and experimental boundary-layer development in a supersonic nozzle at a nominal Mach number of 2 indicates the general validity of the approximations used in the analysis - in particular, the method of extrapolating low-speed skin-friction relations to high Mach number flows. The extrapolation method used assumes that the skin-friction coefficient depend primarily on Reynolds number, provided that the density and the kinematic viscosity are evaluated at surface conditions.
    Keywords: Fluid Mechanics and Thermodynamics
    Type: NACA-TN-2045
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  • 10
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    The Condensation Line of Air and the Heats of Vaporization of Oxygen and Nitrogen (1953)
    In:  CASI
    Details
    Publication Date: 2019-06-28
    Description: The condensation pressure of air was determined over the range of temperature from 60 to 85 K. The experimental results were slightly higher than the calculated values based on the ideal solution law. Heat of vaporization of oxygen was determined at four temperatures ranging from about 68 to 91 K and of nitrogen similarly at four temperatures ranging from 62 to 78 K.
    Keywords: Fluid Mechanics and Thermodynamics
    Type: NACA-TN-2969
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  • 11
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    An Analytical Study of Heat Requirements for Icing Protection of Radomes (1953)
    In:  CASI
    Details
    Publication Date: 2019-06-28
    Description: The heat requirements for the icing protection of two radome configurations have been studied over a range of design icing conditions. Both the protection limits of a typical thermal protection system and the relative effects of the various icing variables have been determined. For full evaporation of all impinging water, an effective heat density of 14 watts per square inch was required. When a combination of the evaporation and running wet surface systems was employed, a heat requirement of 5 watts per square inch provided protection at severe icing and operating conditions.
    Keywords: Fluid Mechanics and Thermodynamics
    Type: NACA-RM-E53A22
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  • 12
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    Generalization of Boundary-Layer Momentum-Integral Equations to Three-Dimensional Flows Including Those of Rotating System (1952)
    In:  CASI
    Details
    Publication Date: 2019-06-28
    Description: The Navier-Stokes equations of motion and the equation of continuity are transformed so as to apply to an orthogonal curvilinear coordinate system rotating with a uniform angular velocity about an arbitrary axis in space. A usual simplification of these equations as consistent with the accepted boundary-layer theory and an integration of these equations through the boundary layer result in boundary-layer momentum-integral equations for three-dimensional flows that are applicable to either rotating or nonrotating fluid boundaries. These equations are simplified and an approximate solution in closed integral form is obtained for a generalized boundary-layer momentum-loss thickness and flow deflection at the wall in the turbulent case. A numerical evaluation of this solution carried out for data obtained in a curving nonrotating duct shows a fair quantitative agreement with the measures values. The form in which the equations are presented is readily adaptable to cases of steady, three-dimensional, incompressible boundary-layer flow like that over curved ducts or yawed wings; and it also may be used to describe the boundary-layer flow over various rotating surfaces, thus applying to turbomachinery, propellers, and helicopter blades.
    Keywords: Fluid Mechanics and Thermodynamics
    Type: NACA-TR-1067
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  • 13
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    Impingement of water droplets on NACA 65(1)-208 and 65(1)-212 airfoils at 4 degrees angle of attack (1953)
    In:  CASI
    Details
    Publication Date: 2019-06-28
    Description: The trajectories of droplets in the air flowing past NACA 65(1)-208 airfoil and an NACA 65(1)-212 airfoil, both at an angle of attack of 4 degrees, were determined. The amount of water in droplet form impinging on the airfoils, the area of droplet impingement, and the rate of droplet impingement per unit area on the airfoil surface affected were calculated from the trajectories and are presented. The amount, extent, and rate of impingement of the NACA 65(1)-208 airfoil are compared with the results for the NACA 65(1)1-212 airfoil. Under similar conditions of operation, the NACA 65(1)-208 airfoil collects less water than the NACA 65(1)-212 airfoil. The extent of impingement on the upper surface of the NACA 65(1)-208 airfoil is much less than on the upper surface of the NACA 65(1)-212 airfoil, but on the lower surface the extents of impingement are about the same.
    Keywords: Fluid Mechanics and Thermodynamics
    Type: NACA-TN-2952
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  • 14
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    Applications of a Conservative Zonal Scheme to Transient and Geometrically Complex Problems (1986)
    In:  Other Sources
    Details
    Publication Date: 2019-07-13
    Description: A conservative zoning technique, wherein the flow field for a finite-difference calculation is divided into several regions to simplify grid generation, is discussed and is applied in the solution of a two-dimensional problem of complex topology. Calculations are performed on two zonal, or patched, grid systems for the supersonic flow over a double-airfoil configuration. The solution is smooth and continuous across the zonal interfaces, and shock waves pass through the boundaries without distortion. In addition, the time accuracy of the zonal boundary method is verified by a two-zone cylinder calculation with a stationary inner and a rotating outer mesh. The feasibility of the zonal approach for use in the solution of geometrically complex and unsteady problems is thus demonstrated.
    Keywords: Fluid Mechanics and Thermodynamics
    Type: Fluid Dynamics; Jun 25, 1984 - Jun 27, 1984; Snowmass, CO; United States|Computers and Fluids (ISSN 0045-7930); 14; 1; 43-58
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  • 15
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    Experimental Investigation of Average Heat-Transfer and Friction Coefficients for Air Flowing in Circular Tubes Having Square-Thread-Type Roughness (1952)
    In:  CASI
    Details
    Publication Date: 2019-06-27
    Description: An investigation of forced-convection heat transfer and associated pressure drops was conducted with air flowing through electrically heated Inconel tubes having various degrees of square-thread-type roughness, an inside diameter of 1/2 inch, and a length of 24 inches. were obtained for tubes having conventional roughness ratios (height of thread/radius of tube) of 0 (smooth tube), 0.016, 0.025, and 0.037 over ranges of bulk Reynolds numbers up to 350,000, average inside-tube-wall temperatures up to 1950deg R, and heat-flux densities up to 115,000 Btu per hour per square foot. Data The experimental data showed that both heat transfer and friction increased with increase in surface roughness, becoming more pronounced with increase in Reynolds number; for a given roughness, both heat transfer and friction were also influenced by the tube wall-to-bulk temperature ratio. Good correlation of the heat-transfer data for all the tubes investigated was obtained by use of a modification of the conventional Nusselt correlation parameters wherein the mass velocity in the Reynolds number was replaced by the product of air density evaluated at the average film temperature and the so-called friction velocity; in addition, the physical properties of air were evaluated at the average film temperature. The isothermal friction data for the rough tubes, when plotted in the conventional manner, resulted in curves similar to those obtained by other investigators; that is, the curve for a given roughness breaks away from the Blasius line (representing turbulent flow in smooth tubes) at some value of Reynolds number, which decreases with increase in surface roughness, and then becomes a horizontal line (friction coefficient independent of Reynolds number). A comparison of the friction data for the rough tubes used herein indicated that the conventional roughness ratio is not an adequate measure of relative roughness for tubes having a square-thread-type element. The present data, as well as those of other investigators, were used to isolate the influence of ratios of thread height to width, thread spacing to width, and the conventional roughness ratio on the friction coefficient. A fair correlation of the friction data was obtained for each tube with heat addition when the friction coefficient and Reynolds number were defined on the basis of film properties; however, the data for each tube retained the curve characteristic of that particular roughness. The friction data for all the rough tubes could be represented by a single line for the complete turbulence region by incorporating a roughness parameter in the film correlation. No correlation was obtained for the region of incomplete turbulence.
    Keywords: Fluid Mechanics and Thermodynamics
    Type: NACA-RM-E52D17 , E-2482
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  • 16
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    Spark Ignition of Flowing Gases. 2: Effect of Electrode Parameters on Energy Required to Ignite a Propane-Air Mixture (1951)
    In:  CASI
    Details
    Publication Date: 2019-06-27
    Description: Research was conducted to determine the effect of the electrode parameters of spacing, configuration, and material' on the energy required for ignition of a flowing propane-air mixture. In addition, the data were used to indicate the energy distribution along the spark length and to confirm previous observations concerning the effect of spark duration on ignition energy requirements. The data were obtained with a mixture at a fuel-air ratio of 0.0835 (by weight), a pressure of 3 inches of mercury absolute, a temperature of 80 F, and a mixture velocity of 5 feet per second. Results showed that the energy required for ignition decreased as the electrode spacing was increased; a minimum energy occurred at. a spacing of 0.65 inch for large electrodes. For small electrodes, the spacing for minimum energy was not sharply defined. Small-diameter electrodes required less energy than large-diameter electrodes if the spacing was less than the optimum distance of 0.65 inch; at a spacing equal to the optimum distance, no difference was noted. Significant effects of electrode material on ignition energy were ascribed to differences in the type of spark discharges produced; glow discharges required higher energy than the arc-glow discharges. With pure glow discharges, the ignition energy was substantially constant for lead, cadmium, brass, aluminum, and tungsten electrodes. A method is described for determining the energy distribution along a glow discharge. It was found that one-third to one-half of the energy in the spark was concentrated in a small region near the cathode electrode, and the remainder was uniformly distributed across the spark gap. It was impossible to ascertain the dependence of ignition on. this distribution. It was also observed that long-duration (600 microsec) sparks required much less energy for ignition than did short-duration (1 microsec) sparks.
    Keywords: Fluid Mechanics and Thermodynamics
    Type: NACA-RM-E51J12 , E-2394
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  • 17
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    Interpretation of Boundary-layer Pressure-rake Data in Flow with a Detached Shock (1950)
    In:  CASI
    Details
    Publication Date: 2019-06-27
    Description: No abstract available
    Keywords: Fluid Mechanics and Thermodynamics
    Type: NACA-RM-E50I29A , REPT-2003
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  • 18
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    Experimental Investigation of Air-cooled Turbine Blades in Turbojet Engine. 2: Rotor Blades with 15 Fins in Cooling-air Passages (1950)
    In:  CASI
    Details
    Publication Date: 2019-06-27
    Description: No abstract available
    Keywords: Fluid Mechanics and Thermodynamics
    Type: NACA-RM-E50I29A
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  • 19
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    Vapor resistant arteries (1989)
    In:  CASI
    Details
    Publication Date: 2019-08-17
    Description: A vapor block resistant liquid artery structure for heat pipes. A solid tube artery with openings is encased in the sintered material of a heat pipe wick. The openings are limited to that side of the artery which is most remote from the heat source. The liquid in the artery can thus exit the artery through the openings and wet the sintered sheath, but vapor generated at the heat source is unlikely to move around the solid wall of the artery and reverse its direction in order to penetrate the artery through the openings. An alternate embodiment uses finer pore size wick material to resist vapor entry.
    Keywords: Fluid Mechanics and Thermodynamics
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  • 20
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    Thermal microstructure measurement system (1985)
    In:  CASI
    Details
    Publication Date: 2019-08-17
    Description: A thermal microstructure measurement system (TMMS) operates autonomously h its own internal power supply and telemeters data to a platform. A thermal array is mounted on a cross-braced frame designed to orient itself normal to existing currents with fixed sensor positioning bars protruding from the cross bars. A plurality of matched thermistors, conductivity probes and inclinometers are mounted on the frame. A compass and pressure transducer are contained in an electronics package suspended below the array. The array is deployed on a taut mooring below a subsurface float. Data are digitized, transmitted via cable to a surface buoy and then telemetered to the platform where the data is processed via a computer, recorded and/or displayed. The platform computer also sends commands to the array via telemetry.
    Keywords: Fluid Mechanics and Thermodynamics
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  • 21
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    Data from Tests of a 1/5-Scale Model of a Proposed High-Speed Submarine in the Langley Full-Scale Tunnel (1950)
    In:  CASI
    Details
    Publication Date: 2019-07-12
    Description: Tests of a 1/5 scale model of a proposed 153-foot high-speed submarine have been conducted in the Langley full-scale tunnel at the request of the Bureau of Ships, Department of the Navy. The test program included: (1) force tests to determine the drag, control effectiveness, and static stability characteristics for a number of model configurations, both in pitch and in yaw, (2) pressure measurements to determine the boundary-layer conditions and flow characteristics in the region of the propeller, and (3) an investigation of the effects of propeller operation on the model aerodynamic characteristics. In response to oral requests from the Bureau of Ships representatives t hat the basic data obtained in these tests be made available to them as rapidly as possible, this data report has been prepared to present some of the more pertinent results. All test results given in the present paper are for the propeller-removed condition and were obtained at a Reynolds number of approximately 22,300,000 based on model length.
    Keywords: Fluid Mechanics and Thermodynamics
    Type: NACA-RM-SL50E09a
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  • 22
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    Experimental Determination of Linear Dynamics of Two-Spool Turbojet Engines (1954)
    In:  CASI
    Details
    Publication Date: 2019-07-12
    Description: Transfer functions descriptive of the response of most engine variables were determined from transient data that were obtained from approximate step inputs in fuel flow and in exhaust-nozzle area. The speed responses of both spools to fuel flow and to turbine-inlet temperature appeared as identical first-order lags. Response to exhaust-nozzle area was characterized by a first-order lag response of the outer-spool speed, accompanied by virtually no change in inner-spool speed.
    Keywords: Fluid Mechanics and Thermodynamics
    Type: NACA-RM-E54J11
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  • 23
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    Wind-Tunnel Investigation at Subsonic and Supersonic Speeds of a Fighter Model Employing a Low-aspect-ratio Unswept Wing and a Horizontal Tail Mounted Well above the Wing Plane - Lateral and Directional Stability (1954)
    In:  CASI
    Details
    Publication Date: 2019-07-12
    Description: The static lateral- and directional-stability characteristics of a high-speed fighter-type airplane, obtained from wind-tunnel tests of a model, are presented. The model consisted of a thin, unswept wing of aspect ratio 2.3 and taper ratio 0.385, a body, and a horizontal tail mounted in a high position on a vertical tail. Rolling-moment, yawing moment, and cross-wind-force coefficients are presented for a range of sideslip angles of -5 deg. to +5 deg, for Mach numbers of 0.90, 1.45, and 1.90. Data are presented which show the effects on the lateral and directional stability of: (1) component parts of the complete model, (2) modification of the empennage so as to provide different heights of the horizontal tail above the wing plane, (3) angle of attack, and (4) dihedral of the wing.
    Keywords: Fluid Mechanics and Thermodynamics
    Type: NACA-RM-SA54H26b
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  • 24
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    Efficiency arcjet thruster with controlled arc startup and steady state attachment (1989)
    In:  CASI
    Details
    Publication Date: 2019-07-12
    Description: An improved efficiency arcjet thruster has a constrictor and electrically-conductive nozzle anode defining an arc chamber, and an electrically-conductive rod having a tip spaced upstream from the constrictor and defining a cathode spaced from the anode by a gap generally coextensive with the arc chamber. An electrical potential is applied to the anode and cathode to generate an electrical arc in the arc chamber from the cathode to anode. Catalytically decomposed hydrazine is supplied to the arc chamber with generation of the arc so as to produce thermal heating and expansion thereof through the nozzle. The constrictor can have a electrically insulative portion disposed between the cathode tip and the nozzle anode, and an electrically-conductive anode extension disposed along the insulative portion so as to define an auxiliary gap with the cathode tip substantially smaller than the gap defined between the cathode and nozzle anode for facilitating startup of arc generation. The constrictor can also include an electrically-conductive electrode with a variable electrical potential to vary the shape of the arc generated in the arc chamber. Also, the cathode is mounted for axial movement such that the gap between its tip and the nozzle anode can be varied to facilitate a generally nonerosive generation of the electrical arc at startup and reliable steady state operation. Further, the arc chamber can have a nonparallel subsonic-to-supersonic transition configuration, or alternatively solely a nonparallel supersonic configuration, for improved arc attachment.
    Keywords: Fluid Mechanics and Thermodynamics
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  • 25
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    Vapor resistant arteries (1989)
    In:  CASI
    Details
    Publication Date: 2019-08-15
    Description: A vapor block resistant liquid artery structure for heat pipes. A solid tube artery with openings is encased in the sintered material of a heat pipe wick. The openings are limited to that side of the artery which is most remote from the heat source. The liquid in the artery can thus exit the artery through the openings and wet the sintered sheath, but vapor generated at the heat source is unlikely to move around the solid wall of the artery and reverse its direction in order to penetrate the artery through the openings. An alternate embodiment uses finer pore size wick material to resist vapor entry.
    Keywords: Fluid Mechanics and Thermodynamics
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  • 26
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    Investigation of High-Subsonic Performance Characteristics of a 12 Degree 21-Inch Conical Diffuser, Including the Effects of Change in Inlet-Boundary-Layer Thickness (1950)
    In:  CASI
    Details
    Publication Date: 2019-07-11
    Description: Investigations were conducted of a 12 degree 21-inch conical diffuser of 2:l area ratio to determine the interrelation of boundary layer growth and performance characteristics. surveys were made of inlet and exit from, longitudinal static pressures were recorded, and velocity profiles were obtained through an inlet Reynolds number range, determined From mass flows and based on inlet diameter of 1.45 x 10(exp 6) to 7.45 x 10(exp 6) and a Mach number range of 0.11 to approximately choking. These investigations were made to two thicknesses of inlet boundary layer. The mean value, over the entire range of inlet velocities, of the displacement thickness of the thinner inlet boundary layer was approximately 0.035 inch and that of the thicker inlet boundary layer was approximately six times this value. The loss coefficient in the case of the thinner inlet boundary layer had a value between 2 to 3 percent of the inlet impact pressure over most of the air-flow range. The loss coefficient with the thicker inlet boundary layer was of the order of twice that of the thinner inlet boundary layer at low speeds and approximately three times at high speeds. In both cases the values were substantially less than those given in the literature for fully developed pipe flow. The static-pressure rise for the thinner inlet boundary layer was of the order of 95 percent of that theoretically possible over the entire speed range. For the thicker inlet boundary layer the static pressure rise, as a percentage of that theoretically possible, ranged from 82 percent at low speeds to 68 percent at high speeds.
    Keywords: Fluid Mechanics and Thermodynamics
    Type: NACA-RM-L9H10
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  • 27
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    High-Subsonic Performance Characteristics and Boundary-Layer Investigations of a 12 10-Inch-Inlet-Diameter Conical Diffuser (1950)
    In:  CASI
    Details
    Publication Date: 2019-07-11
    Description: Performance and boundary-layer data were taken in a 12 degree 10-inch inlet-diameter conical diffuser of 2:1 exit- to inlet-area ratio. These data were taken for two inlet-boundary-layer conditions. The first condition was that of a thinner inlet boundary later (boundary-layer displacement thickness, delta* approximately equal to 0.034) produced by an inlet section approximately 1 inlet diameter in length between the entrance bell and the diffuser. The second condition was a thicker inlet boundary layer (delta* approximately equal to 0.120) produced by an additional inlet section length of approximately 6 diameters. Longitudinal static-pressure distributions were measured fro wall static orifices. Transverse total- and static-pressure surveys were made at the inlet and exit stations. Boundary-layer velocity distributions were measured at seven stations between the inlet and exit. These data were obtained for a Reynolds number (based on inlet diameter) range of 1 x 10(exp 6) to 3.9 x 10(exp 6). The corresponding Mach number range was from M = 0.2 to choking. At the maximum-power-available condition supersonic flow was obtained as far as 4.5 inches downstream from the diffuser inlet with a maximum Mach number of M approximately equal to 1.5. The total-pressure loss through the diffuser in percentage of inlet dynamic pressure was approximately 2.5 percent for the thinner inlet boundary later and 5.5 percent for the thicker inlet boundary later over the lower subsonic range. These valued increased with increasing flow rate- the values for the thicker inlet boundary later more than those for the thinner inlet boundary layer. The diffuser effectiveness, expressed as the ratio of the actual static-pressure rise to the ideal static-pressure rise, was about 85 percent for the thinner inlet boundary layer and about 67 percent for the thicker inlet boundary later in the lower subsonic range. These values decrease with increasing flow rate. Separated flow was observed for both inlet-boundary-layer conditions in the region of adverse pressure gradient just downstream of the transition curvature from inlet section to diffuser. The flow for the thinner-inlet-boundary-layer condition did not fully re-establish itself along the diffuser walls. The thicker inlet-boundary-layer flow, while not completely re-establishing the normal flow pattern downstream of the separated region, did re-establish more successfully than the thinner inlet boundary layer.
    Keywords: Fluid Mechanics and Thermodynamics
    Type: NACA-RM-L50C02a
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  • 28
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    Oscillation pressure device for dynamic calibration of pressure transducers (1987)
    In:  CASI
    Details
    Publication Date: 2019-08-28
    Description: Method and apparatus for obtaining dynamic calibrations of pressure transducers. A calibration head (15), a flexible tubing (23) and a bellows (20) enclose a volume of air at atmospheric pressure with a transducer (11) to be calibrated subject to the pressure inside the volume. All of the other apparatus in the drawing apply oscillations to bellows (20) causing the volume to change thereby applying oscillating pressures to transducer (11) whereby transducer (11) can be calibrated.
    Keywords: Fluid Mechanics and Thermodynamics
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  • 29
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    Jet pump-drive system for heat removal (1987)
    In:  CASI
    Details
    Publication Date: 2019-08-28
    Description: The invention does away with the necessity of moving parts such as a check valve in a nuclear reactor cooling system. Instead, a jet pump, in combination with a TEMP, is employed to assure safe cooling of a nuclear reactor after shutdown. A main flow exists for a reactor coolant. A point of withdrawal is provided for a secondary flow. A TEMP, responsive to the heat from said coolant in the secondary flow path, automatically pumps said withdrawn coolant to a higher pressure and thus higher velocity compared to the main flow. The high velocity coolant is applied as a driver flow for the jet pump which has a main flow chamber located in the main flow circulation pump. Upon nuclear shutdown and loss of power for the main reactor pumping system, the TEMP/jet pump combination continues to boost the coolant flow in the direction it is already circulating. During the decay time for the nuclear reactor, the jet pump keeps running until the coolant temperature drops to a lower and safe temperature where the heat is no longer a problem. At this lower temperature, the TEMP/jet pump combination ceases its circulation boosting operation. When the nuclear reactor is restarted and the coolant again exceeds the lower temperature setting, the TEMP/jet pump automatically resumes operation. The TEMP/jet pump combination is thus automatic, self-regulating and provides an emergency pumping system free of moving parts.
    Keywords: Fluid Mechanics and Thermodynamics
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  • 30
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    Space vehicle thermal rejection system (1989)
    In:  CASI
    Details
    Publication Date: 2019-08-28
    Description: A space vehicle thermal heat rejection system 10 utilizing separate optimized heat pipe components for the functions of heat acquisition, heat transport, and heat rejection. A honeycomb panel heat pipe evaporator section 20 performs the function of heat acquisition, and forms a closed thermodynamic system with a dual channel heat pipe transport section 30, which performs the function of heat transport. A plurality of truss or channel core heat pipe rejection fins 41 form the condenser section 40, which performs the function of heat rejection. A common wall 32 separates the condenser section 40 from the transport section 30. Using the above heat pipe components and having efficient interfacing between them results in high performance factors for the overall system.
    Keywords: Fluid Mechanics and Thermodynamics
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  • 31
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    Fluid leak indicator (1989)
    In:  CASI
    Details
    Publication Date: 2019-08-28
    Description: A fluid leak indicator (30) for detecting and indicating leaks in visually inaccessible fluid tubing joints (20, 21), such as those obstructed by insulation (24), includes a bag system (25) and a wicking system (30) surrounding or wrapping the joints (20, 21) under the visual obstructing material (24). Leaking fluid is collected in the bag (25) or on the wicking material (34) where it is conducted along the wicking material (34) to a visibly accessible capturing transparent indicator bulb (35) for providing a visual indication of the leak without requiring a chemical change in the capturing indicator bulb (35).
    Keywords: Fluid Mechanics and Thermodynamics
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  • 32
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    Exact Solutions of Equations of Gas Dynamics (1950)
    In:  CASI
    Details
    Publication Date: 2019-07-13
    Description: This document presents equations for the two-dimensional stationary problem of gas dynamics, and uses them to derive other equations, including equations for vorticity.
    Keywords: Fluid Mechanics and Thermodynamics
    Type: NACA-TM-1260 , Prikladnaya Matematika I Mekhanica; 11; 193-198
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  • 33
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    The Boundary Layers in Fluids with Little Friction (1950)
    In:  CASI
    Details
    Publication Date: 2019-07-13
    Description: The vortices forming in flowing water behind solid bodies are not represented correctly by the solution of the potential theory nor by Helmholtz's jets. Potential theory is unable to satisfy the condition that the water adheres at the wetted bodies, and its solutions of the fundamental hydrodynamic equations are at variance with the observation that the flow separates from the body at a certain point and sends forth a highly turbulent boundary layer into the free flow. Helmholtz's theory attempts to imitate the latter effect in such a way that it joins two potential flows, jet and still water, nonanalytical along a stream curve. The admissibility of this method is based on the fact that, at zero pressure, which is to prevail at the cited stream curve, the connection of the fluid, and with it the effect of adjacent parts on each other, is canceled. In reality, however, the pressure at these boundaries is definitely not zero, but can even be varied arbitrarily. Besides, Helmholtz's theory with its potential flows does not satisfy the condition of adherence nor explain the origin of the vortices, for in all of these problems, the friction must be taken into account on principle, according to the vortex theorem.
    Keywords: Fluid Mechanics and Thermodynamics
    Type: NACA-TM-1256 , Zeitschrift fuer Mathematik und Physik; 56; 1; 1-37
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  • 34
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    Subsonic Gas Flow Past A Wing Profile (1950)
    In:  CASI
    Details
    Publication Date: 2019-07-13
    Description: The use of the linearized equations of Chaplygin to calculate the subsonic flow of a gas permits solving the problem of the flow about a wing profile for absence and presence of circulation. The solution is obtained in a practical convenient form that permits finding all the required magnitudes for the gas flow (lift, lift moment velocity distribution over the profile, and critical Mach number). This solution is not expressed in simple closed form; for a certain simplifying assumption, however, the equations of Chaplygin can be reduced to equations with constant coefficients, and solutions are obtained by using only the mathematical apparatus of the theory of functions of a complex variable. The method for simplifying the equations was pointed out by Chaplygin himself. These applied similar equations to the solution of the flow problem and obtained a solution for the case of the absence of circulation.
    Keywords: Fluid Mechanics and Thermodynamics
    Type: NACA-TM-1250 , Prikladnaya Matematika I Mekhanika; 11; 1; 105-118
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  • 35
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    On the Formation of Shock Waves in Subsonic Flows With Local Supersonic Velocities (1950)
    In:  CASI
    Details
    Publication Date: 2019-07-13
    Description: In the flow about a body with large subsonic velocity if the velocity of the approaching flow is sufficiently large, regions of local supersonic velocities are formed about the body. It is known from experiment that these regions downstream of the flow are always bounded by shock waves; a continuous transition of the supersonic velocity to the subsonic under the conditions indicated has never been observed. A similar phenomenon occurs in pipes. If at two cross sections of the pipe the velocity is subsonic and between these sections regions of local supersonic velocity are formed without completely occupying a single cross section, these regions are always bounded by shock waves.
    Keywords: Fluid Mechanics and Thermodynamics
    Type: NACA-TM-1251 , Prikladnaya Matematika I Mekhanika; 11; 190-202
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  • 36
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    Flow Analysis of Space Shuttle Feed Line 17-inch Disconnect Valve (1988)
    In:  CASI
    Details
    Publication Date: 2019-07-13
    Description: A steady incompressible three-dimensional viscous flow analysis has been conducted for the Space Shuttle External Tank/Orbiter propellant feed line disconnect flapper valves with upstream elbows. The full Navier-Stokes code, INS3D, is modified to handle interior obstacles. Grids are generated by SVTGD3D code. Two dimensional initial grids in the flow cross section with and without the flappers are improved by elliptic smoothing to provide better orthogonality, clustering and smoothness to the three dimensional grid. The flow solver is tested for stability and convergence in the presence of interior flappers. An under-relaxation scheme has been incorporated to improve the solution stability. Important flow characteristics such as secondary flows, recirculation, vortex and wake regions, and separated flows are observed. Computed values for forces, moments, and pressure drop are in satisfactory agreement with water flow test data covering a maximum tube Reynolds number of 3.5 x 10(exp 6). The results will serve as a guide to improved design and enhanced testing of the disconnect.
    Keywords: Fluid Mechanics and Thermodynamics
    Type: AIAA PAPER 88-3788 , AIAA/ASME/SIAM/APS National Fluid Dynamics Congress; Jul 25, 1988 - Jul 28, 1988; Cincinnati, OH; United States
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  • 37
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    Use of an Expansion Tube to Examine Scramjet Combustion at Hypersonic Velocities (1989)
    In:  Other Sources
    Details
    Publication Date: 2019-07-13
    Description: Combustion testing at total enthalpy conditions corresponding to flight Math numbers in excess of 12 requires the use of impulse facilities. The expansion tube is the only operational facility of its size which can provide these conditions without excessive oxygen dissociation or driver gas contamination. Expansio tube operation is described herein and the operational parameters having the largest impact on its performance are determined. These are: driver-to-intermediate chamber pressure ratio, driver gas molecular weight and specific heat ratio, and driver gas temperature. Increases in the lase named parameter will markedly affect the test section static pressure. Preliminary calibration tests are discussed and test gas conditions which have been achieved are presented. Calculated and experimental test times are compared and the parameters affecting test time are discussed. The direction of future work using this important experimental tool is indicated.
    Keywords: Fluid Mechanics and Thermodynamics
    Type: AIAA Paper-89-2536 , AIAA/ASME/SAE/ASEE 25th Joint Propulsion Conference; Jul 10, 1989 - Jul 12, 1989; Monterey, CA; United States
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  • 38
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    Some Studies on the Flow of a Gas in the Region of Transition Through the Velocity of Sound (1950)
    In:  CASI
    Details
    Publication Date: 2019-07-11
    Description: The two-dimensional motion of an incompressible fluid about a closed contour with a definite velocity in magnitude and direction at infinity is considered. If, without changing the direction of the velocity at infinity, the magnitude is increased, the configuration of the streamlines remains unchanged and only the numbering of the stream function changes. There exists only one family of curves that can serve as streamlines in the incompressible flow about a given contour (at a given angle of attack); for example, the contour of an airplane wing. The case is quite different with a compressible fluid.
    Keywords: Fluid Mechanics and Thermodynamics
    Type: NACA-TM-1252 , Izvestia Akademii Nauk, SSSR, No. 3; 153-259; Rept-3
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  • 39
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    Effect of Various Blade Modifications on Performance of A16-Stage Axial-Flow Compressor. V - Effect on Over-All Performance Characteristics of a 20-Percent Reduction in Solidity of the Fourteenth Through Sixteenth Stage Rotors (1952)
    In:  CASI
    Details
    Publication Date: 2019-07-12
    Description: The performance of a 16-stage axial-flow compressor, in which the mean-radius solidity was reduced from 1.28 to 1.02 in the fourteenth through sixteenth stage rotors was determined. The performance of this modification was compared with that of the compressor with original rotors. The reduced solidity resulted in slightly improved performance.
    Keywords: Fluid Mechanics and Thermodynamics
    Type: NACA-RM-E52D22
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  • 40
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    Preliminary Data on the Effects of Inlet Pressure Distortions on the J57-P-1 Turbojet Engine (1954)
    In:  CASI
    Details
    Publication Date: 2019-07-12
    Description: An investigation to determine the steady-state and surge characteristics of the J57-P-1 two-spool turbojet engine with various inlet air-flow distortions was conducted in the altitude wind tunnel at the NACA Lewis laboratory. Along with a uniform inlet total-pressure distribution, one circumferential and three radial pressure distortions were investigated. Data were obtained over a complete range of compressor speeds both with and without intercompressor air bleed at a flight Mach number of 0.8 and at altitudes of 35,000 and 50,000 feet. Total-pressure distortions of the magnitudes investigated had very little effect on the steady-state operating line for either the outer or inner compressor. The small radial distortions investigated also had engine over that obtained with the uniform inlet pressure distribution. The circumferential distortion, however, raised the minimum speed at which the engine could operate without encountering surge when the intercompressor bleeds were closed. This increase in minimum speed resulted in a substantial reduction in the operable speed range accompanied by a reduction in the altitude operating limit.
    Keywords: Fluid Mechanics and Thermodynamics
    Type: NACA-RM-SE54K19
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  • 41
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    Preliminary Altitude Performance Data of J71-A2 Turbojet Engine Afterburner (1954)
    In:  CASI
    Details
    Publication Date: 2019-07-12
    Description: The performance and operational characteristics of the J71-A2 turbojet-engine afterburner were investigated for a range of altitudes from 23,000 to 60,000 feet at a flight Mach number of 0,9 and at flight Mach numbers of 0.6, 0.9, and 1.0 at an altitude of 45,000 feet. The combustion performance and altitude operational limits, as well as the altitude starting characteristics have been determined.
    Keywords: Fluid Mechanics and Thermodynamics
    Type: NACA-RM-SE54J06
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  • 42
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    Circulation controlled rotor blade tip vent valve (1986)
    In:  CASI
    Details
    Publication Date: 2019-07-12
    Description: Inadvertent slot opening in a circulation controlled rotor due to plenum valve leakage is averted by venting duct pressure below a control minimum. A vent valve is disclosed.
    Keywords: Fluid Mechanics and Thermodynamics
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  • 43
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    Device and method for determining freezing points (1986)
    In:  CASI
    Details
    Publication Date: 2019-07-12
    Description: A freezing point method and device (10) are disclosed. The method and device pertain to an inflection point technique for determining the freezing points of mixtures. In both the method and device (10), the mixture is cooled to a point below its anticipated freezing point and then warmed at a substantially linear rate. During the warming process, the rate of increase of temperature of the mixture is monitored by, for example, thermocouple (28) with the thermocouple output signal being amplified and differentiated by a differentiator (42). The rate of increase of temperature data are analyzed and a peak rate of increase of temperature is identified. In the preferred device (10) a computer (22) is utilized to analyze the rate of increase of temperature data following the warming process. Once the maximum rate of increase of temperature is identified, the corresponding temperature of the mixture is located and earmarked as being substantially equal to the freezing point of the mixture. In a preferred device (10), the computer (22), in addition to collecting the temperature and rate of change of temperature data, controls a programmable power supply (14) to provide a predetermined amount of cooling and warming current to thermoelectric modules (56).
    Keywords: Fluid Mechanics and Thermodynamics
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  • 44
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    Forced flow evaporator for unusual gravity conditions (1987)
    In:  CASI
    Details
    Publication Date: 2019-07-12
    Description: Low efficiency heat transfer in evaporators subject to unusual gravitational conditions is avoided through the use of a spiral evaporator conduit 12 receiving at an inlet 14 a vaporizable coolant at least partly in the liquid phase. Flow of the coolant through the conduit 12 demists the coolant by centrifuging the liquid phase against a pressurre wall 44 of the conduit 12. Vapor flow 40 induces counterrotating vortices 46, 48 which circulate the liquid phase coolant around the interior of the conduit 12 to wet all surfaces thereof.
    Keywords: Fluid Mechanics and Thermodynamics
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  • 45
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    Investigation of Surge Characteristics of XJ34-WE-32 Turbojet Engine (1951)
    In:  CASI
    Details
    Publication Date: 2019-07-12
    Description: Surge characteristics of the XJ34-WE-32 turbojet engine were determined over a range of altitudes. Several typical oscillograph traces during which surge occurred are presented. The effect of altitude on the surge line and it's relation to the steady-state operating region are shown.
    Keywords: Fluid Mechanics and Thermodynamics
    Type: NACA-RME51J02
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  • 46
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    Investigation of Downwash, Sidewash, and Mach Number Distribution behind a Rectangular Wing at a Mach Number of 2.41 (1950)
    In:  CASI
    Details
    Publication Date: 2019-07-12
    Description: An investigation of the nature of the flow field behind a rectangular circular-arc wing has been conducted in the Langley 9-inch supersonic tunnel. Pitot- and static-pressure surveys covering a region of flow behind the wing have been made together with detailed pitot surveys throughout the region of the wake. In addition, the flow direction has been measured using a weathercocking vane measurements. Theoretical calculations of the variation of both downwash and sidewash with angle of attack using Lagerstrom's superposition method have been made. In addition the effect of the wing thickness on the sidewash with the wing at 0 angle of attack has been evaluated. Near an angle of attack of 0, agreement between theory and experiment is good, particularly for the downwash results, except in the plane of the wing, inboard of the tip. In this region the proximity of the shed vortex sheet and the departure of the spanwise distribution of vorticity from theory would account for the disagreement. At higher angles of attack prediction of downwash depends on a knowledge of the location of the trailing vortex sheet, in order that the downwash may be corrected for its displacement and distortion. The theoretical location of the trailing vortex sheet, based on the theoretical downwash values integrated downstream from the wing trailing edge, is shown to differ widely from the experimental case. The rolling-up of the trailing vortex sheet behind the wing tip is evidenced by both the wake surveys and the flow-angle measurements.
    Keywords: Fluid Mechanics and Thermodynamics
    Type: NACA-RM-L50G12 , NACA Rept 1340
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  • 47
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    Performance of 15-Stage Experimental J71 Axial-Flow Compressor: II - Individual Stage Performance Characteristics (1954)
    In:  CASI
    Details
    Publication Date: 2019-07-12
    Description: The first four stages were found to cause a major part of the poor low-speed efficiency of this compressor. The low design-speed over-all pressure ratio at surge was caused by the first and the twelfth to fifteenth stages. The multiple over-all performance curves in the intermediate-speed range were at least partly the result of double-branched characteristic curves for the third and seventh stages.
    Keywords: Fluid Mechanics and Thermodynamics
    Type: NACA-RM-SE54J19
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  • 48
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    Fuel cell crimp-resistant cooling device with internal coil (1986)
    In:  CASI
    Details
    Publication Date: 2019-07-12
    Description: A cooling assembly for fuel cells having a simplified construction whereby coolant is efficiently circulated through a conduit arranged in serpentine fashion in a channel within a member of such assembly. The channel is adapted to cradle a flexible, chemically inert, conformable conduit capable of manipulation into a variety of cooling patterns without crimping or otherwise restricting of coolant flow. The conduit, when assembled with the member, conforms into intimate contact with the member for good thermal conductivity. The conduit is non-corrodible and can be constructed as a single, manifold-free, continuous coolant passage means having only one inlet and one outlet. The conduit has an internal coil means which enables it to be bent in small radii without crimping.
    Keywords: Fluid Mechanics and Thermodynamics
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  • 49
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    Labyrinthine turbine-rotor-blade tip seal (1987)
    In:  CASI
    Details
    Publication Date: 2019-07-12
    Description: Means for sealing the tip 18 of a rotor turbine blade 10 against tip leakage flow comprising a multiplicity of recesses 30 formed in the surface of the tip 18. The recesses 30 are preferably formed in a labyrinthine or slaggered pattern which interposes at least one recess 30 in every leakage flow path across the tip 18 from the pressure side 26 to the suction side 28 of the blade 10.
    Keywords: Fluid Mechanics and Thermodynamics
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  • 50
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    Heating Rate Distributions at Mach 10 on a Circular Body Earth-to-Orbit Transport Vehicle (1985)
    In:  CASI
    Details
    Publication Date: 2019-07-13
    Description: Among the concepts being considered for future Earth-to-orbit transport vehicles are fully reusable single-stage systems which take off vertically and land horizontally. Because these vehicles carry their own propellant internally, they are much larger than the present Space Shuttle Orbiter. One such single-stage vehicle under study is the circular body configuration which has the advantages of simple structural design and large volume-to-weight ratio. As part of an overall evaluation of this configuration, a series of heat transfer and surface flow tests were conducted. The phase-change paint and oil-flow tests were performed in the Langley 31-Inch Mach-10 Tunnel at angles of attack from 20 through 40 degrees in 5-degree increments. Heat-transfer coefficient data are presented for all angles of attack and detailed oil-flow photographs are shown for windward and leeward surfaces at 25 and 40 degrees angle of attack. In many ways, heating was similar to that previously determined for the Shuttle Orbiter so that, in a cursory sense, existing thermal protection systems would appear to be adequate for the proposed circular-body configurations.
    Keywords: Fluid Mechanics and Thermodynamics
    Type: AIAA Paper 85-0974 , AIAA 20th Thermophysics Conference; Jun 19, 1985 - Jun 21, 1985; Williamsburg, VA; United States
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  • 51
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    Notes on the Prediction of Shock-induced Boundary-layer Separation (1953)
    In:  CASI
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    Publication Date: 2019-07-12
    Description: The present status of available information relative to the prediction of shock-induced boundary-layer separation is discussed. Experimental results showing the effects of Reynolds number and Mach number on the separation of both laminar and turbulent boundary layer are given and compared with available methods for predicting separation. The flow phenomena associated with separation caused by forward-facing steps, wedges, and incident shock waves are discussed. Applications of the flat-plate data to problems of separation on spoilers, diffusers, and scoop inlets are indicated for turbulent boundary layers.
    Keywords: Fluid Mechanics and Thermodynamics
    Type: NACA-RM-L53I16a
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  • 52
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    Pulsed electrothermal thruster (1989)
    In:  CASI
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    Publication Date: 2019-07-12
    Description: A plasma electrothermal thruster includes a capillary passage in which a plasma discharge is formed and directed out of an open end of the passage into a supersonic nozzle. Liquid supplied to the capillary passage becomes partially atomized to cool a confining surface of the passage. The plasma discharge is formed as the atomized liquid flows out of the open end into a supersonic equilibrium nozzle. The discharge can have a duration greater than the two way travel time of acoustic energy in the capillary to cause the plasma to flow continuously through the nozzle during the time of the discharge pulse.
    Keywords: Fluid Mechanics and Thermodynamics
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  • 53
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    External artery heat pipe (1989)
    In:  CASI
    Details
    Publication Date: 2019-07-12
    Description: An improved heat pipe with an external artery. The longitudinal slot in the heat pipe wall which interconnects the heat pipe vapor space with the external artery is completely filled with sintered wick material and the wall of the external artery is also covered with sintered wick material. This added wick structure assures that the external artery will continue to feed liquid to the heat pipe evaporator even if a vapor bubble forms within and would otherwise block the liquid transport function of the external artery.
    Keywords: Fluid Mechanics and Thermodynamics
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    Boundary Layer Effect on the Surface Pressure of an Infinite Cone in Supersonic Flow (1951)
    In:  CASI
    Details
    Publication Date: 2019-08-26
    Description: The theory of Taylor and Maccoll (Ref,1) gives the surface pressure on an infinite cone in supersonic flow as a function of the cone vertex angle and the free stream Mach number and static pressure for a gas of vanishing viscosity. When a slender conical probe is used together with an impact pressure probe to determine the static pressure and Mach number in a low density gas stream, it is desirable to have some theoretical estimate of the effect of viscous boundary layer on the probe readings. Theoretical and experimental results with respect to impact probes have been presented in Refs. 5 and 6. A simple approximation for a conical probe based on linearized supersonic flow and compressible boundary layer theory is presented here.
    Keywords: Fluid Mechanics and Thermodynamics
    Type: HE-150-80
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    Power frame (1988)
    In:  CASI
    Details
    Publication Date: 2019-08-15
    Description: A rotor stage disposed within an annular fluid flowpath in a turbomachine is disclosed. The rotor stage includes outer and inner rings and a plurality of first and second airfoils. The outer and inner rings define flowpath surfaces for said flowpath. The first and second airfoils extend between the rings for transferring energy between the fluid and the rotor stage. At least one of the first airfoils surrounds means for transmitting energy across the flowpath.
    Keywords: Fluid Mechanics and Thermodynamics
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  • 56
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    Vortex generator for flow control (1989)
    In:  CASI
    Details
    Publication Date: 2019-08-15
    Description: Fluidics flow control of a multiphase supply using a cylindrical chamber is achieved by introducing the supply flow radially into the chamber. The supply flow exits through a port in the center at the chamber. A control fluid is then introduced tangentially about 90.degree. upstream from the supply port. A second control fluid port may be added about 90.degree. upstream from the first control fluid port, but preferably two sets of supply and control ports are added with like ports diametrically opposite each other. The control fluid flows against the circular wall of the control chamber, which introduces a vortex in the flow of the supply flow that decays into a spiral path to the exit port in the center of the chamber. The control flow rate may thus be used to control the spiral path, and therefore the supply flow rate through the exit port.
    Keywords: Fluid Mechanics and Thermodynamics
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  • 57
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    Sphere based fluid systems (1989)
    In:  CASI
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    Publication Date: 2019-08-15
    Description: Systems are described for using multiple closely-packed spheres. In one system for passing fluid, a multiplicity of spheres lie within a container, with all of the spheres having the same outside diameter and with the spheres being closely nested in one another to create multiple interstitial passages of a known size and configuration and smooth walls. The container has an inlet and outlet for passing fluid through the interstitial passages formed between the nested spheres. The small interstitial passages can be used to filter out material, especially biological material such as cells in a fluid, where the cells can be easily destroyed if passed across sharp edges. The outer surface of the spheres can contain a material that absorbs a constitutent in the flowing fluid, such as a particular contamination gas, or can contain a catalyst to chemically react the fluid passing therethrough, the use of multiple small spheres assuring a large area of contact of these surfaces of the spheres with the fluid. In a system for storing and releasing a fluid such as hydrogen as a fuel, the spheres can include a hollow shell containing the fluid to be stored, and located within a compressable container that can be compressed to break the shells and release the stored fluid.
    Keywords: Fluid Mechanics and Thermodynamics
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  • 58
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    Forced air heat sink apparatus (1989)
    In:  CASI
    Details
    Publication Date: 2019-08-15
    Description: A high efficiency forced air heat sink assembly employs a split feed transverse flow configuration to minimize the length of the air flow path through at least two separated fin structures. Different embodiments use different fin structure material configurations including honeycomb, corrugated and serpentine. Each such embodiment uses a thermally conductive plate having opposed exterior surfaces; one for receiving a component to be cooled and one for receiving the fin structures. The serpentine structured fin embodiment employs a plurality of fin supports extending from the plate and forming a plurality of channels for receiving the fin structures. A high thermal conductivity bondant, such as metal-filled epoxy, may be used to bond the fin structures to either the plate or the fin supports. Dip brazing and soldering may also be employed depending upon the materials selected.
    Keywords: Fluid Mechanics and Thermodynamics
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  • 59
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    Direct Simulation of Reentry Flows with Ionization (1989)
    In:  CASI
    Details
    Publication Date: 2019-08-15
    Description: The Direct Simulation Monte Carlo (DSMC) method is applied in this paper to the study of rarefied, hypersonic, reentry flows. The assumptions and simplifications involved with the treatment of ionization, free electrons and the electric field are investigated. A new method is presented for the calculation of the electric field and handling of charged particles with DSMC. In addition, a two-step model for electron impact ionization is implemented. The flow field representing a 10 km/sec shock at an altitude of 65 km is calculated. The effects of the new modeling techniques on the calculation results are presented and discussed.
    Keywords: Fluid Mechanics and Thermodynamics
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  • 60
    Electronic Resource
    Electronic Resource
    Synthese, Struktur und katalytische Aktivität von μ-(Alkylthio)-dicarbonyl-μ-chloro-bis(tri-tert-butylarsan)-dirhodium-Komplexen (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 2738-2745 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis, Structure, and Catalytic Activity of μ-(Alkylthio)-dicarbonyl-μ-chloro-bis(tri-tert-butylarsane)dirhodium ComplexesTetracarbonyl-di-μ-chloro-dirhodium (1) reacts with tri-tert-butylarsane (2) and alkyl trimethylsilyl sulfides (4) to give complexes [Rh2(CO)2(AstBu3)2Cl(SR)] (5a-c). The complexes 5b and c with the surface active trialkoxysilyl groups [R=(MeO)3SiCH2CH2, (MeO)3SiCH2CH2CH2] are bound to fused silica support. The X-ray structural analysis of[Rh2(CO)2(AstBu3)2Cl(StBu)] (5a) indicates a cis-configuration of the tri-tert-butylarsane ligands. The new complexes catalyze the hydroformylation of cyclohexene, and the isomerization of allylbenzene (8) into cis- and trans-β-methylstyrene (9). The soluble complex 5a was shown to be an extremely effective olefin hydrogenation catalyst, whereas the supported complexes 6b and c were completely inactive in this process.
    Notes: Durch Umsetzung von Tetracarbonyl-di-μ-chloro-dirhodium (1) mit Tri-tert-butylarsan (2) und Alkyl(trimethylsilyl)sulfiden (4) werden die Komplexe [Rh2(CO)2(AstBu3)2Cl(SR)] (5a-c) dargestellt. Die Komplexe 5b und c mit Trialkoxysilyl-Gruppen [R=(MeO)3SiCH2CH2, (MeO)3SiCH2CH2CH2] werden auf Silicagel fixiert. Die Röntgenstrukturanalyse von [Rh2(CO)2- (AstBu3)2Cl(StBu)] (5a) zeigt das Vorliegen von cis-konfigurierten Tri-tert-butylarsan-Gruppen. Die neuen Komplexe katalysieren die Hydroformylierung von Cyclohexen und die Isomerisierung von Allylbenzol (8) zu cis- und trans-β-Methylstyrol (9). Während lösliches 5a die Hydrierung von Olefinen katalysiert, sind die Heterogenkatalysatoren 6b und c hierbei völlig inaktiv.
    Additional Material: 3 Ill.
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    URL: http://dx.doi.org/10.1002/cber.19851180716
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    Brückenkopf-olefinische Isomere des Triquinacens: Derivate des Tricyclo[5.2.1.04,10]deca-1,5,8- und -1,6,8-triens (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 2757-2776 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Bridgehead Olefinic Isomers of Triquinacene: Derivatives of Tricyclo[5.2.1.04,10]deca-1,5,8- and -1,6,8-trieneBridgehead halides 12 and 13 of triquinacene (2) with soft nucleophiles undergo a syn-stereoselective SN2′ reaction forming derivatives of tricyclo[5.2.1.04,10]deca-1,5,8-triene 15 and 17, respectively, and of tricyclo[5.2.1.04,10]deca-1,6,8-triene 18. The relative stability of these bridgehead olefins is discussed with regard to force field calculations as well as semiempirical MNDO calculations.
    Notes: Brückenkopf-Mono- 12 und -Dihalogenide 13 des Triquinacens (2) reagieren mit weichen Nucleophilen im Sinne einer syn-stereoselektiven SN2′-Reaktion zu Derivaten des Tricyclo[5.2.1.04,10]-deca-1,5,8-triens 15 bzw. 17 und des Tricyclo[5.2.1.04,10]deca-1,6,8-triens 18. Die relative Stabilität dieser Brückenkopf-Olefine wird anhand von Kraftfeld-Rechnungen sowie semiempirischen MNDO-Rechnungen diskutiert.
    Additional Material: 1 Ill.
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    URL: http://dx.doi.org/10.1002/cber.19851180718
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    Stabilitätskonstanten und thermodynamische Werte für die Bildung von 1:1- und 2:1-Komplexen von Kronenethern mit Alkali- und Erdalkali-Ionen in Methanol (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 2746-2756 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Stability Constants and Thermodynamic Values for the Formation of 1:1- and 2:1-Complexes of Crown Ethers with Alkali and Alkaline-earth Ions in MethanolThe determination of stability constants and thermodynamic values for the reaction of crown ethers with alkali-, alkaline-earth ions, and the silver ion was achieved by calorimetric titration in methanol. Through modification of the experimental conditions it is possible to measure separately the formation of 1:1- and 2:1-complexes (ratio of ligand to cation). With the exception of Ag+ and Ca2+ all ions examined form both kinds of complexes with the various 15 C 5 ligands. The complex stabilities are influenced by enthalpic and entropic contributions. 18 C 6 and DC 18 C 6, having a bigger diameter than 15 C 5, show a definite increase of the stability of 1:1-complexes. Only the Cs+ ion with the largest radius forms 2:1-complexes. A good agreement is found with values determined potentiometrically for the 1:1- and 2:1-complex formation of Na+.
    Notes: Die Komplexstabilitäten und thermodynamischen Werte für die Reaktion von Kronenethern mit Alkali-, Erdalkali-Ionen und dem Silber-Ion in Methanol wurden mittels kalorimetrischer Titrationen bestimmt. Durch Veränderung der experimentellen Bedingungen ist es möglich, sowohl die Bildung von 1:1- als auch 2:1-Komplexen (Verhältnis von Ligand zu Kation) getrennt voneinander zu messen. Mit Ausnahme von Ag+ und Ca2+ bilden alle untersuchten lonen beide Arten von Komplexen mit den verschiedenen 15 K 5-Liganden. Die Komplexstabilitäten werden von enthalpischen und entropischen Faktoren beeinflußt. 18 K 6 und DC 18 K 6, die einen größeren Durchmesser als 15 K 5 besitzen, zeigen einen deutlichen Anstieg der Stabilität der 1:1-Komplexe. 2:1-Komplexe bildet nur noch das Cs+ -Ion mit dem größten Radius. Ein Vergleich mit potentiometrisch bestimmten Daten für die 1:1- und 2:1-Komplexbildung von Na+ zeigt gute Übereinstimmung.
    Additional Material: 4 Ill.
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    URL: http://dx.doi.org/10.1002/cber.19851180717
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    Anodische Oxidation O-benzoylierter α-Hydroxyessigsäuren - Ein Beitrag zur Reaktivität anodisch umgepolter Carboxylat-Ionen (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 2777-2788 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Anodic Oxidation of O-Benzoylated α-Hydroxyacetic Acids - A Contribution to the Reactivity of Anodic Oxidated Carboxylate Ions - “Umpolung”Anodic oxidation of O-benzoylated α-hydroxyacetic acid 1 at graphite electrodes in methanol leads to the corresponding mixed acylals 2 and methyl benzoates 3. The rate 2:3 depends on the substitution of the aromatic ring and can be correlated to Hammett's σ-values.
    Notes: Bei der anodischen Oxidation O-benzoylierter α-Hydroxyessigsäuren 1 an Graphitelektro-den in Methanol entstehen die zugehörigen gemischten Acylale 2 und die entsprechenden Benzoesäure-methylester 3. Das Produktverhältnis 2:3 ist abhängig von der Substitution des Aromaten und läßt sich mit den Hammettschen σ-Werten korrelieren.
    Additional Material: 2 Ill.
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    URL: http://dx.doi.org/10.1002/cber.19851180719
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    Cyclopentadienylsubstituierte Germylene und Stannylene als Komplexliganden (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 2789-2797 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Cyclopentadienyl-substituted Germylenes and Stannylenes as Complex LigandsTransition metal complexes of chloro(pentamethylcyclopentadienyl)germylene and -stannylene with pentacarbonylchromium and -tungsten bound to the 4B-element (3a, b, 5a, b) are available by alkylation of the ylide complexes Cl2(THF)El→M(CO)5 (El=Ge, Sn; M=Cr, W, 1a, b, 4a, b). X-Ray structure studies on the germylene complex Me5C5(Cl)-Ge→ W(CO)5 (3b) show that involving the lone-pair of the 4B-element in a metal-metal bond changes the distorted h5-Me5C5 coordination of the uncomplexed germylene to a highly symmetrical h2-structure.
    Notes: Übergangsmetallkomplexe des Chlor(pentamethylcyclopentadienyl)germylens und -stannylens mit am 4B-Element gebundener Pentacarbonylchrom- bzw. -wolframeinheit (3a, b, 5a, b) werden durch Alkylierung der Ylidkomplexe Cl2(THF)El→M(CO)5 (El=Ge,Sn; M=Cr, W, 1a, b, 4a, b) erhalten. Röntgenographische Untersuchungen am Germylenkomplex Me5C5(Cl)Ge→W(CO)5 (3b) zeigen, daß sich die Inanspruchnahme des “lone-pair” am 4B-Element in einem Wechsel der verzerrten h5-Me5C5-Koordination im freien Germylen zu einer hochsymmetrischen h2-Koordination äußert.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19851180720
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    Kleine Ringe, 52. Oxidative Ringöffnung von Tetra-tert-butyltetrahedran. - Kristall- und Molekularstruktur von Tetra-tert-butyl-cyclobutenylium-Ionen (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 2798-2810 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Small Rings, 52. Oxidative Ring Opening of Tetra-tert-butyltetrahedrane. - Crystal and Molecular Structure of Tetra-tert-butylcylobutenylium IonsOxidative ring opening of tetra-tert-butyltetrahedrane yields cyclobutenylium ions of type 4 or 6. Their spectroscopic properties, but especially the crystal structure determination of 4h and 6c, show the characteristics expected for homocyclopropenylium salts. Because of 1,3-bonding interactions the ions are folded (4h: 37.3°, 6c: 36.4°), the 1,3-distances across the four-membered ring are short (4h: 1.806 Å, 6c: 1.833 Å).
    Notes: Bei der oxidativen Ringöffnung von Tetra-tert-butyltetrahedran entstehen Cyclobutenylium-Salze vom Typ 4 oder 6. Deren spektroskopische Eigenschaften, vor allem aber röntgenographische Strukturbestimmungen von 4h oder 6c, rechtfertigen es, diese Verbindungen als Homocyclopropenylium-Salze zu benennen. Die Ionen sind aufgrund von 1,3-bindenden Wechselwirkungen stark gefaltet (4h: 37.3°, 6c: 36.4°), der 1,3-Abstand im Vierring ist kurz (4h: 1.806 Å, 6c: 1.833 Å).
    Additional Material: 2 Ill.
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    URL: http://dx.doi.org/10.1002/cber.19851180721
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    Tetrafluor-1,2-ethandisulfenyldichlorid - ein Baustein für neue Schwefel-Stickstoff-Kohlenstoff-Heterocyclen (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 2811-2821 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Tetrafluoro-1,2-ethanedisulfenyl Dichloride - a Precursor for new Sulfur-Nitrogen-Carbon Heterocycles1,3,2-Dithiazolidines (3a-c) are obtained by reaction of the title compound CISCF2CF2SCI 1 with disilylated amines (Me3Si)2NR (R=Me, Ph, SiMe3). Reaction with (Me3-SiNR)2SO2 (R=Me, SiMe3) yields 1,3,5,2,4-trithiadiazepanes 4a, b, whereas N,N′-disilylated urea leads to the dithiadiazepanon 5. CISCF2CF2SSCI and SO2[N(SiMe3)2]2 react to yield the eight-membered tetrahiadiazocane 6. Using the dilution principle, with disilylated piperazine 7 in a molar ratio of 1:1 the sixteen-membered ring 9 is formed, which contains two piperazine units within the ring skeleton. The crystal structure of 1,3,5,2,4-trithiadiazepane-tetraphenylphosphonium chloride 10 is reported. 4b reacts with 1 to yield 11 in which a ten-membered ring is bridged by an SO2 group. By changing the reaction conditions a product of twice the molecular weight is formed, for which a tricyclic system with a central fourteen-membered ring 13 is proposed.
    Notes: Die Titelverbindung CISCF2CF2SCI 1 reagiert mit disilylierten Aminen (Me3Si)2NR (R=Me, Ph, SiMe3) glatt zu 1,3,2-Dithiazolidinen (3a-c). Bei der Umsetzung mit (Me3SiNR)2SO2 (R=Me, SiMe3) werden die 1,3,5,2,4-Trithiadiazepane 4a, b erhalten; mit N,N′-disilyliertem Harnstoff bildet sich das 1,5,2,4-Dithiadiazepanon 5. CISCF2CF2SSCI und SO2[N(SiMe3)2]2 reagieren zum achtgliedrigen 1,2,4,6,3,5-Tetrathiadiazocan 6. Durch Anwendung des Verdünnungsprinzips wird mit disilyliertem Piperazin 7 im Molverhältnis 1:1 der sechzehngliedrige Ring 9 synthetisiert, welcher zwei Piperazineinheiten im Ringgerüst enthält. Von 1,3,5,2,4-Trithiadiazepan-Tetraphenylphosphoniumchlorid 10 wird die Röntgenstrukturanalyse mitgeteilt. 4b reagiert mit 1 zu 11; hier liegt ein zehngliedriger Ring vor, der durch eine SO2-Gruppe überbrückt ist. Bei veränderter Reaktionsführung erhält man ein Produkt der doppelten Molekülmasse, dem eine tricyclische Struktur zugeschrieben wird, die einen zentralen vierzehngliedrigen Ring enthält (13).
    Additional Material: 4 Ill.
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    URL: http://dx.doi.org/10.1002/cber.19851180722
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    Darstellung und Eigenschaften von 1,3-Dithietan-2-on-1,1-dioxid (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 2852-2857 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Preparation and Properties of 1,3-Dithietan-2-one 1,1-DioxideOzonolysis of 2-(benzoylmethylene)-1,3-dithietane 1,1-dioxide (7), prepared via oxidation of 2-(benzoylmethylene)-1,3-dithietane (6), yielded 1,3-dithietan-2-one 1,1-dioxide (5) as the first 1,3-dithietane with an α-oxosulfone structure. Diethyl (1,3-dithietan-2-ylidene)malonate S,S-dioxide (2) did not react with ozone. 5 can be regarded as a potential sulfene precursor. However, in the pyrolysis of 5 sulfene could not be detected so far.
    Notes: Ozonolyse von 2-(Benzoylmethylen)-1,3-dithietan-1,1-dioxid (7), dargestellt durch Oxidation von 2-(Benzoylmethylen)-1,3-dithietan (6), ergab 1,3-Dithietan-2-on-1,1-dioxid (5) als erstes 1,3-Dithietan mit α-Oxosulfonstruktur. (1,3-Dithietan-2-yliden)malonsäure-diethylester-S,S-dioxid (2) setzte sich dagegen nicht mit Ozon um. 5 kann als potentieller Sulfen-Bildner angesehen werden. Bei der Pyrolyse von 5 konnte jedoch bislang kein Sulfen nachgewiesen werden.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19851180724
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    Cycloadditionen des 1-(4-Methoxyphenyl)-2,2-dimethylvinyl-Kations an Olefine (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 2974-2992 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Cycloadditions of 1-(4-Methoxyphenyl)-2,2-dimethylvinyl Cation to Olefins1-Bromo-1-(4-methoxyphenyl)-2-methyl-1-propene (1) reacts with cyclohexene, cycloheptene, (Z)-cyclooctene and the silver salts AgBF4, via the vinyl cation 2 by cycloaddition to form the cyclobutenes 7b-d. Cyclobutene 8 is obtained from (Z)- and (E)- and (E)-2-butene. Besides the cyclobutene derivatives, the isomeric cyclopropane compound 10d is also formed in the reaction of 1 with (Z)-cyclooctene under the same conditions, with cyclopentene only the cyclopropane derivative is formed. Copper (I) triflate-olefin complexes can be used in place of silver slats to generate the vinyl cation 2, whereby cyclobutenes 7 are formed preferably. - In contrast to vinyl bromide 1, 1-(4-methoxyphenyl)-2-methyl-1-propenyl triflate (5) reacts with cyclopentene, cyclohexene, cyloheptene, (Z)- and (E)-cyclooctene to give mostly the corresponding cyclopropane derivatives 10. The stereoisomeric cyclopropyl compounds 19 are obtained from (Z)- and (E)-2-butene. - The mechanisms of silver-catalysed and silver-free cycloaddition reactions are discussed.
    Notes: 1-Brom-1-(4-methoxyphenyl)-2-methyl-1-propen (1) reagiert mit Cyclohexen, Cyclohepten, (Z)-Cycloocten und den Silbersalzen AgBF4 bzw. AgSbF6 über das Vinylkation 2 unter Cycloaddition überwiegend zu den Cyclobutenen 7b-d. Mit (Z)- und (E)-2- Buten wird das Cyclobuten 8 erhalten. Bei der Umsetzung von 1 unter den gleichen Bedingungen entsteht mit Cyclopenten das Cyclopropanderivat 10a, mit (Z)-Cycloocten entsteht neben dem Cyclobutenderivat 7d die isomere Cyclopropanverbindung 10d. An Stelle der Silbersalze können auch Kupfer(I)-triflat-Olefin-Komplexe zur Erzeugung des Vinylkations 2 verwendet werden, wobei ebenfalls bevorzugt die Cyclobutene 7 erhalten werden. - Im Gegensatz zum Vinylbromid 1 reagiert das 1-(4-Methoxyphenyl)-2-methyl-1-propenyl-triflat (5) mit Cyclopenten, Cyclohexen, Cyclohepten und (Z)- bzw. (E)-Cycloocten überwiegend zu den entsprechenden Cyclopropanderivaten 10. Mit (Z)- und (E)-2-Buten werden die stereoisomeren Cyclopropylverbindungen 19 erhalten. - Die Mechanismen der silbersalzkatalysierten und silberfreien Cycloadditionsreaktionen werden diskutiert.
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    Masthead (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985) 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19851180801
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    Versuche zur Darstellung von Endiazeniumsalzen (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 3011-3019 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Experiments to Form Enediazenium Salts(2-Alkoxyvinyl)diazenium salts 9 and 14 are obtained by O-alkylation of glyoxal- (4) and methylglyoxal monodimethylhydrazone (13), resp., with alkyl trifluoromethanesulfonates. Bromination of N-(trimethylsilyl)enehydrazines 16 and 18 in pentane leads to the formation of solid, hydrophilic substances, for which the structures of enediazenium salts 19, α-bromohydrazones 20, or ammonium salts 21 are discussed. These compounds react with nucleophiles (alcohols, amines, thiols, and indole) to give hydrazones 24a-i substituted at C-2.
    Notes: Glyoxal- (4) und Methylglyoxal-monodimethylhydrazon (13) werden durch Trifluormethansulfonsäure-alkylester am Sauerstoff zu (Alkoxyvinyl)diazeniumsalzen 9 bzw. 14 alkyliert. N-Silylierte Enhydrazine 16 und 18ergeben mit Brom in Pentan feste, hydrophile Verbindungen, für die die Strukturen von Endiazeniumsalzen 19 oder α-Bromhydrazonen 20 bzw. Ammoniumsalzen 21 diskutiert werden. Diese Verbindungen addieren Alkohole, Amine, Thiole sowie Indol als Nucleophile am C-Atom 2 unter Bildung der Hydrazone 24a-i.
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    1,3-Dithienium- und 1,3-Dithioleniumsalze, IV. 1,3-Dithian-2-ylium-tetrafluoroborate - neue Agenzien zur Synthese von 1-Deuterioaldehyden (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 3166-3171 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: 1,3-Dithienium- and 1,3-Dithiolenium Salts, IV. 1,3-Dithian-2-ylium Tetrafluoroborates - New Agents for the Synthesis of 1-DeuterioaldehydesThe 1,3-dithian-2-ylium tetrafluoroborates 3 react in good yields with sodium borohydride (4) to give the 1,3-dithianes 6 and with sodium borodeuteride (5) to form the precursors 7 of 1-deuterated aldehydes 8. Three 1-deuterioaldehydes 8 are synthesized exemplarily by dethioacetalization of 7.
    Notes: Die 1,3-Dithian-2-ylium-tetrafluoroborate 3 reagieren in guten Ausbeuten mit Natriumborhydrid (4) zu den 1,3-Dithianen 6 und mit -deuterid (5) unter Bildung der Vorläufer 7 von 1-deuterierten Aldehyden 8. Exemplarisch werden drei 1-Deuterioaldehyde 8 durch Dethioacetalisierung von 7 synthetisiert.
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    Kleine Ringe, 54. Cyclopentadienon (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 3196-3204 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Small Rings, 54. CyclopentadienoneCyclopentadienone (1) can be generated by photolysis or pyrolysis of several precursors and isolated in an argon matrix. It dimerizes even on thawing of the matrix (38 K). The IR and UV spectroscopic properties of 1 are discussed.
    Notes: Cyclopentadienon (1) kann aus mehreren Vorstufen photolytisch oder pyrolytisch erzeugt und in einer Argonmatrix bei 10 K isoliert werden. Es dimerisiert bereits beim Auftauen der Matrix (38 K). Die IR- und UV-spektroskopischen Eigenschaften von 1 werden beschrieben.
    Additional Material: 2 Ill.
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    URL: http://dx.doi.org/10.1002/cber.19851180819
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    Metallorganische Verbindungen des Iridiums und Rhodiums, XXIII. Chelatphosphan-substituierte Iridaheterocyclen des Typs (chel-P3)[(2)] (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 3188-3195 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Organometallic Compounds of Iridium and Rhodium, XXIII. Chelate Phosphane-Substituted Iridaheterocycles of the Form (chel-P3)When treated with chelate phosphanes chel-P3, aryl iridium(I) compounds of the type Ir(CO)[C6H4-nMen-CH3-(2)](PPh3)2 readily undergo PPh3 substitution, CO insertion, and oxidative benzyl C-H addition to give metallaheterocyclic complexes of formula fac-(Chel-P3) 1-4) (C6H4-nMen=C6H4, C6H3Me-(6), C6H2Me2-(4,6); chel-P3=PhP[(CH2)3PPh2]2, MeP[(CH2)3PPh2]2, PhP[(CH2)2PPh2]2, MeC(CH2-PPh2)3). The cyclic iridium(III) species have been investigated by IR, 1H, and 31P NMR spectroscopy as well as by a single crystal X-ray diffraction analysis of fac-[PhP(CH2CH2-CH2PPh2)2] 1a).
    Notes: Aryliridium(I)- Verbindungen des Typs Ir(CO)[C6H4-nMen-CH3-(2)](PPh3)2 reagieren mit Chelatphosphanen chel-P3 unter PPh3-Substitution, CO-Insertion und oxidativer Benzyl C - H-Addition spontan zu metallaheterocyclischen Iridaindanon-Spezies der Formel fac-(chel-P3)1 - 4) (C6H4-nMen=C6H4, C6H3Me-(6), C6H2Me2-(4, 6); chel-P3=PhP[(CH2)3PPh2]2, MeP[(CH2)3PPh2]2, PhP[(CH2)2PPh2]2 MeC(CH2PPh2)3). Die cyclischen Iridium(III)-Verbindungen wurden spektroskopisch (IR, 1H- und 31P-NMR) sowie röntgenographisch (fac-[PhP(CH2CH2CH2PPh2)2]-, 1 a) untersucht.
    Additional Material: 1 Ill.
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    URL: http://dx.doi.org/10.1002/cber.19851180818
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    Synthesen substituierter elektronenreicher N-Sulfonyl-1-azabutadiene (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 3217-3226 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Syntheses of Substituted Electron-rich N-Sulfonyl-1-azabutadienesThe syntheses of alkylthio- und arylthio-substituted electron-rich N-sulfonyl-1-azabutadienes 3a - e, 5a - d, and 10a - c, of dialkylamino-substituted N-sulfonyl-1-azabutadienes 6a - g, and the sulfoxide 11 are described.
    Notes: Es wird über die Synthesen der alkylthio- bzw. arythiosubstituierten elektronenreichen N-Sulfonyl-1-azabutadiene 3a - e sowie 5a - d und 10a - c, über die dialkylaminosubstituierten N-Sulfonyl-1-azabutadiene 6a - g und das Sulfoxid 11 berichtet.
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    URL: http://dx.doi.org/10.1002/cber.19851180821
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    (tert-Butylimino)[tert-butyl(trimethylsilyl)amino]boran, ein Aminoiminoboran, und seine Reaktionen (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 3205-3216 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: (tert-Butylimino)[tert-butyl(trimethylsilyl)amino]borane, an Aminoiminoborane, and its ReactionsThe title compound (1b) was prepared by gas-phase elimination of FSiMe3 from the corresponding diaminoborane as a distillable liquid, storable at -30°C, dimerizing at room temperature. Additions to the more unsaturated BN-bond are typical for 1b. Protic reagents are added to give the aminoboranes 3a - c. The aminoboranes 3d - h are formed by ethylo-, azido-, or chloroboration or by azidosilation of 1b, respectively. The chloroboration can be followed by the novel formation of the diazadiboretidines 2e - g. Iminoboranes give a ring closure with 1b, the diazadiboretidines 2b,h being formed. The addition of the CO-bond of aldehydes to 1b yields the oxazaboretidines 4a - c. The [2 + 3]-cycloaddition products 5a,b are isolated by the reaction of 1b with azide- or nitrone-type 1,3-dipolar systems. The borane 1b behaves as a dienophile towards cyclopentadiene with the bicyclic molecule 6 as the product. By X-ray analysis, the central ring-unit of 2f turns out to be a BNBN-rhombus with the acute angles at the N-atoms.
    Notes: Die Titelverbindung (1b) erhält man als destillierbare, bei -30°C lagerfähige, bei Raumtemperatur dimerisierende Flüssigkeit durch Gasphaseneliminierung von FSiMe3 aus dem entsprechenden Diaminoboran. Typisch für 1b sind Additionen an die stärker ungesättigte BN-Bindung. Protonenaktive Stoffe addieren sich zu den Aminoboranen 3a - c. Durch Ethylo-, Azido- oder Chloroborierung sowie durch Azidosilierung erhält man die Aminoborane 3d - h. Die Chloroborierung kann mit einer neuartigen Bildung der Diazadiboretidine 2e - g einhergehen. Iminoborane addieren sich an 1b zu den Diazadiboretidinen 2b,h. Die Addition der CO-Bindung von Aldehyden führt zu den Oxazaboretidinen 4a - c. 1,3-Dipolare Verbindungen vom Azid- bzw. Nitrontyp ergeben die Fünfring-Verbindungen 5a,b. Mit Cyclopentadien reagiert 1b als Dienophil zum Bicyclus 6. Für die Verbindung 2f ergibt sich als zentrale Baueinheit röntgenographisch eine BNBN-Raute mit spitzen Winkeln an den N-Atomen.
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    URL: http://dx.doi.org/10.1002/cber.19851180820
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    Zur Kenntnis der Cycloaddukte aus 3-Imino-3H-1,2,4-dithiazolen und Nitrilen: Herstellungsbedingungen und Molekülstruktur (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 3241-3247 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Cycloadducts from 3-Imino-3H-1,2,4-dithiazoles and Nitriles: Conditions of Preparation and StructureA series of (thiocarbamoylimino)-1,2,4-thiadiazolines (2) was prepared by ring-opening cycloaddition from some imino-1,2,4-dithiazoles (1) and different nitriles. The structure of 2j was determined by X-ray analysis and compared with an isomeric thiadiazolidine (3).
    Notes: Eine Reihe von (Thiocarbamoylimino)-1,2,4-thiadiazolinen (2) wurde durch ringöffnende Cycloaddition aus einigen Imino-1,2,4-dithiazolen (1) und verschiedenen Nitrilen hergestellt. Von 2j wurde eine Röntgenstrukturanalyse angefertigt und mit der eines isomeren Thiadiazolidins (3) verglichen.
    Additional Material: 2 Ill.
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    URL: http://dx.doi.org/10.1002/cber.19851180823
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    Hochdruckversuche, XIII. Die Reaktion von tert-Butylisonitril und von Toluol mit Bicyclo[2.2.1]hepten unter Hochdruckbedingungen (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 3275-3286 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: High Pressure Experiments, XIII. Reaction of tert-Butyl Isonitrile and of Toluene with Bicyclo[2.2.1]heptene (Norbornene) at High PressureAt pressure of about 10 kbar tert-butyl isonitrile reacts with bicyclo[2.2.1]heptene (norbornene) in low yield to give many products of which addition compounds 2 - 11 were identified. With pure toluene exo-2-benzylbicyclo[2.2.1]heptane (10) was found. With oxygen containing toluene also exo-2,3-epoxybicyclo[2.2.1]heptane (2) was isolated. The structure of methanopyrroloindole 6 is confirmed by an X-ray structure analysis.
    Notes: Unter einem Druck von etwa 10 kbar verbindet sich tert-Butylisonitril mit Bicyclo-[2.2.1]hepten (Norbornen) in geringer Ausbeute zu mehreren Produkten, von denen die Verbindungen 2 - 11 aufgeklärt werden konnten. Mit reinem Toluol entsteht in 41proz. Ausbeute exo-2-Benzylbicyclo[2.2.1]heptan (10). Mit sauerstoffhaltigem Toluol wird auch exo-2,3-Epoxybicyclo[2.2.1]heptan (2) erhalten. Von Methanopyrroloindol 6 wurde eine Röntgenstrukturanalyse durchgeführt.
    Additional Material: 2 Ill.
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    URL: http://dx.doi.org/10.1002/cber.19851180827
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    Synthese mittlerer und großer Ringe, XI. Bicyclo[n.2.2]alkene aus überbrückten Oxepinen - Synthese von 3,6-Pentanooxepin-4,5-dicarbonsäure-dimethylester und 6,9-Dihydro[5]paracyclophan-7,8-dicarbonsäure-dimethylester (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 3287-3298 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis of Medium and Large Rings, XI. Bicyclo[n.2.2]alkenes from Bridged Oxepins - Synthesis of Dimethyl 3,6-Pentanooxepin-4,5-dicarboxylate and Dimethyl 6,9-Dihydro[5]paracyclophane-7,8-dicarboxylateA new approach to bicyclo[5.2.2]undec(adi)enes and bicyclo[6.2.2]dodecene derivatives, starting from cycloheptanone and cyclooctanone is described. Key steps of this synthesis are the conversion of 3,4-pentano- and -hexanofuran to the β,β′-bridged oxepins 2 and the transannular addition of bromine to 2. The dibromides 3a and 3b can be debrominated to give 3c and 3d in high yield.
    Notes: Ein neuer Zugang zu Bicyclo[5.2.2]undec(adi)enen und Bicyclo[6.2.2]dodecen-Derivaten, ausgehend von Cycloheptanon und Cyclooctanon, wird beschrieben. Schlüsselschritte dieser Synthese sind die Überführung von 3,4-Pentano- und -Hexanofuran in die β,β′-überbrückten Oxepine 2 und eine transannulare Addition von Brom an 2. Die Dibromide 3a und 3b lassen sich in hohen Ausbeuten zu 3c und 3d entbromieren.
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    Kohlenhydrat-Modelle, I. Kinetische und thermodynamische Effekte bei Acetalisierungsreaktionen enantiomerenreiner Thiolactole (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 3299-3310 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Carbohydrate-Model Compounds, I. Kinetic and Thermodynamic Effects in Acetal Formation of Enantiomerically Pure ThiolactolsThe synthesis of the enantiomerically pure thiolactol 1 is described. Depending on reaction conditions either (R)-2 or (S)-2 reacts with preference in acetal formation with racemic 1-phenylethanol (rac-2).
    Notes: Die Herstellung des enantiomerenreinen Thiolactols 1 wird beschrieben. Bei der Acetalisierung mit racemischem 1-Phenylethanol (rac-2) reagiert je nach Wahl der Reaktionsbedingungen entweder (R)-2 oder (S)-2 bevorzugt.
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    URL: http://dx.doi.org/10.1002/cber.19851180829
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    Aliphatische Flüssigkristalle, 2. Einige nematische Derivate des all-trans-Perhydrophenanthrens (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 3332-3349 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Aliphatic Liquid Crystals, 2. Some Nematic Derivatives of all-trans-PerhydrophenanthreneA stereoselective synthesis of the all-trans-7-alkylperhydro-2-phenanthrenols 15a - f in 11 steps and 28 liquid crystalline esters 16 of 15a - f are described, additionally some further derivatives of 7-alkylperhydro-2-phenanthrenol. An X-ray structure analysis of ester 16ec is reported.
    Notes: Die stereoselektive Synthese der all-trans-7-Alkylperhydro-2-phenanthrenole 15a - f in 11 Stufen und 28 flüssigkristalline Ester 16 von 15a - f werden beschrieben, daneben einige weitere Derivate der 7-Alkylperhydro-2-phenanthrenole. Vom Ester 16ec wurde eine Röntgenstrukturanalyse durchgeführt.
    Additional Material: 3 Ill.
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    URL: http://dx.doi.org/10.1002/cber.19851180832
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    Komplexierung von Blei(II) durch Azakronenether und Kryptanden in Methanol (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 3408-3412 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Complexation of Lead(II) by Aza Crown Ethers and Cryptands in MethanolThe stability of PbII complexes with the mono- and bicyclic ligands 1 - 5 in methanol was determined by potentiometric titrations using an ion-selective lead(II) electrode. Reaction enthalpies ΔH were measured by calorimetric titrations. Substitution of the protons at the nitrogen atoms of aza crown 1b by the long decyl chains in 1d leads to a great increase in ΔH, whereas the complex stability is scarcely influenced. Benzo anellands (3, 4) reduce the ligand flexibility and cause a decrease in reaction enthalpies. The reaction entropies are nearly unchanged.
    Additional Material: 2 Ill.
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    URL: http://dx.doi.org/10.1002/cber.19851180837
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    Cycloaddition of Singlet Oxygen and 4-Phenyl-4H-1,2,4-triazole-3,5-dione to 7-Substituted 1,3,5-Cyclooctatrienes (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 3357-3379 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Cycloaddition von Singulettsauerstoff und 4-Phenyl-4H-1,2,4-triazol-3,5-dion mit 7-substituierten 1,3,5-CyclooctatrienenDie Cycloadditionen von 7-substituierten (X; Y) 1,3,5-Cyclooctatrienen 3 (N3; H), 4 (OAc; H), 5 (OEt; OEt), 6 (Me; H) und 7 (iPr; H) mit Singulettsauerstoff (1O2) und 4-Phenyl-4H-1,2,4-triazol-3,5-dion (PTAD) wurden untersucht. Singulettsauerstoff reagierte mit diesen Cyclooctatrienen aus dem bicyclischen Valenzisomeren (Bicyclo[4.2.0]octa-2,4-dien) heraus zu den entsprechenden tricyclischen Endoperoxiden. Bicyclische Endoperoxide, ausgehend von monocyclischen Valenzisomeren (1,3,5-Cyclooctatrien), wurden lediglich bei den alkylsubstituierten Derivaten 6 (Me; H) und 7 (iPr; H) erhalten. Die Cyclcoaddition mit PTAD führte zu den bicyclischen und tricyclischen Urazolen, mit Ausnahme des Acetals 5 (OEt; OEt), welches nur das tricyclische Produkt gab. Das Bromderivat 2 reagierte weder mit 1O2 noch mit PTAD. Kontrollexperimente mit der Stammverbindung zeigten, daß die Cycloadditionsprodukte entsprechend den mono- und bicyclischen Valenzisomerenanteilen des Eduktgemisches erhalten wurden.
    Notes: The cycloaddition of the 7-substituted (X; Y) 1,3,5-cyclooctatrienes 3 (N3; H), 4 (OAc; H), 5 (OEt; OEt), 6 (Me; H), and 7 (iPr; H) with singlet oxygen (1O2) and 4-phenyl-4H-1,2,4-triazole-3,5-dione (PTAD) was investigated. Singlet oxygen gave with all cyclooctatrienes the corresponding tricyclic endoperoxides derived from the bicyclic valence isomers (bicyclo[4.2.0]octa-2,4-dienes). The corresponding bicyclic endoperoxides derived from the monocyclic valence isomers (1,3,5-cyclooctatriene) were only obtained for the alkyl-substituted derivatives 6 (Me; H) and 7 (iPr; H). PTAD cycloaddition led to both the bicyclic and tricyclic urazoles, except with the acetal 5 which gave only tricyclic product. The bromo derivative 2 did not react with 1O2 nor PTAD. Control experiments with the parent cyclooctatriene showed that the cycloaddition products were derived from the “static” amounts of the monocyclic and bicyclic valence isomers in the substrate mixture.
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    Decarboxylierungsprodukt von Hexahydrophthalsäureanhydrid: Struktur und spektroskopische Eigenschaften (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 3413-3418 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Product of Decarboxylation of Hexahydrophthalic Anhydride: Structure and Spectroscopic PropertiesThe decarboxylation of some dicarboxylic anhydrides by catalytic influence of tertiary amines occurs at surprisingly low temperature (T≥80°C). The product 12, formed from two molecules of hexahydrophthalic anhydride 6 with loss of one molecule of carbon dioxide, has been isolated and characterized by spectroscopic investigations and X-ray structure analysis.
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  • 84
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    [2 + n]-Cycloadditionen des [Bis(trimethylsilyl)methylen]-[(trimethylsilyl)ethinyl]phosphans (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 3419-3423 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: [2 + n]-Cycloadditions of [Bis(trimethylsilyl)methylene][(trimethylsilyl)ethynyl]phosphane[2 + n]-Cycloadditions of phosphaalkene 1 with sulfur, selenium, 2,3-dimethylbutadiene, diphenyldiazomethane, and trimethylsilyl azide leading to 2, 3, 11, 14, and 15 are reported.
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  • 85
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    Zur Lewis-Acidität von Nickel(0), II. Methylentriorganylphosphoran-Komplexe von Nickel(0) (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 298-312 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: On the Lewis Acidity of Nickel(0), II. Methylenetriorganylphosphorane Complexes of Nickel(0)Methylenetriorganylphosphoranes R3P = CH2 (R = CH3, C6H5) react with Ni(CDT) and Ni(C2H4)3 to form the (methylenetriorganylphosphorane)(alkene)nickel(0) complexes (R3PCH2)Ni(CDT) (R = CH3, 2) and (R3PCH2)Ni(C2H4)2) (R = CH3, C6H5, 4, 5). On treatment with CO the ethene complexes give the known carbonyl complexes (R3PCH2)Ni(CO)3 (R = CH3, C6H5, 9, 10) in pure form. 2 and 4 decompose at room temperature to give Me3PNi(CDT) and Me3PNi(C2H4)2; cyclopropane is produced in the presence of ethene.  -  The stability of the CH2—Ni0 bond in the methylenetriorganylphosphorane complexes falls in the series Ni(CO)3 〉 Ni(C2H4)2 〉 Ni(CDT), corresponding to declining Lewis acidity of the nickel atom. 13C NMR evidence indicates that in the same sequence the P—CH2 bond also becomes weakened. The thermally induced elimination of methylene shows that the nickel bonded methylene group has appreciable carbenoid character.
    Notes: Methylentriorganylphosphorane R3P = CH2 (R = CH3, C6H5) reagieren mit Ni(CDT) und Ni(C2H4)3 zu den (Methylentriorganylphosphoran)(alken)nickel(0)-Komplexen (R3PCH2) Ni(CDT) (R = CH3, 2) und (R3PCH2)Ni(C2H4)2(R = CH3, C6H5, 4, 5). Die Ethen-Komplexe ergeben mit CO die bereits bekannten Carbonyl-Komplexe (R3PCH2)Ni(CO)3(R = CH3, C6H5, 9, 10) in reiner Form. 2 und 4 gehen bei Raumtemperatur in Me3PNi(CDT) und Me3PNi(C2H4)2 über, wobei sich in Gegenwart von Ethen Cyclopropan bildet.  -  Die Stabilität der CH2—Ni0-Bindung in den Methylentriorganylphosphoran-Komplexen verringert sich mit der in der Reihe Ni(CO)3 〉 Ni(C2H4)2 〉 Ni(CDT) abfallenden Lewis-Acidität des Nickels. Aus den 13C-NMR-Spektren ist ableitbar, daß sich in gleicher Sequenz auch die P—CH2-Bindungsordnung vermindert. Die thermisch induzierte Methylen-Abspaltung läßt auf einen carbenoiden Charakter der an Nickel(0) gebundenen Methylengruppen schließen.
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    Zur Lewis-Acidität von Nickel(0), III. Alkalimetall-hydridotrialkylaluminat-Komplexe von Ni(CDT) (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 313-322 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: On the Lewis Acidity of Nickel(0), III. Alkali Metal Hydridotrialkylaluminate Complexes of Ni(CDT)Ni(CDT) reacts with hydridotrialkylaluminates of the alkali metals in ether/THF or ether/amine mixtures at temperatures below -50°C to form the temperature-sensitive compounds [MA(n-Donor)n]+[R3Al—H—Ni(CDT)]- (1-7) (MA = Li, Na; R = Me, Et, iBu). An Al—H—Ni three-centre bond is present in these complexes. On the basis of NMR data, the strength of the hydridoaluminate-nickel bond and the charge on nickel, caused by the hydridoaluminate residue, are compared with the corresponding characteristics of other ligand-Ni(CDT) complexes in which donor-acceptor σ-bonds are present.
    Notes: Ni(CDT)Abkürzungen: CDT = trans, trans, trans-1,5,9-Cyclododecatrien, COD = 1,5-Cyclooctadien, MA+ (solvatisiertes) Alkalimetall-Ion, PMDTA = N,N,N′,N″N″-Pentamethyldiethylentriamin, TMEDA = N,N,N′,N′-Tetramethylethylendiamin. reagiert mit Alkalimetall-hydridotrialkylaluminaten in Ether/THF-oder Ether/Amin-Mischungen als Lösungsmittel unterhalb von -50°C zu den thermisch labilen Verbindungen [MA(n-Donor)n]+[R3Al—H—Ni(CDT)]- (1-7) (MA = Li, Na; R = Me, Et, iBu). In diesen Komplexen liegt eine Al—H—Ni-Mehrzentrenbindung vor. Anhand NMR-spektroskopischer Daten lassen sich die Stärke der Hydridoaluminat-Nickel-Bindung und die Beladung des Nickels durch den Hydridoaluminat-Rest mit den Bindungsverhältnissen in anderen Ligand-Ni(CDT)-Komplexen mit Donor-Akzeptor-σ-Bindungen vergleichen.
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    Neue Reagenzien, XXIX. Synthese, Stabilität und präparative Anwendung von (Triphenylplumbyl)methyllithium (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 370-379 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: New Reagents, XXIX. Synthesis, Stability, and Preparative Applications of (Triphenylplumbyl)methyllithium(Triphenylplumbyl)methyllithium (2), obtained from well accessible starting compounds by iodine-Li- or plumbyl-Li exchange, is applied as a reagent for the introduction of the (triphenylplumbyl)methyl group into alkyl halides, aldehydes, ketones, oxiranes, and organoelement halides.
    Notes: (Triphenylplumbyl)methyllithium (2), durch Iod-Li- oder Plumbyl-Li-Austausch mit Phenyllithium in Tetrahydrofuran aus gut zugänglichen Ausgangssubstanzen erhältlich, wird als Reagenz zur Einführung der (Triphenylplumbyl)methyl-Gruppe in Alkylhalogenide, Aldehyde, Ketone, Oxirane und Organoelementhalogenide angewandt.
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    Notiz zur Reaktion des 3-Iminophenoxazins mit Ammoniak und Aminen (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 397-400 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Note on the Reaction of 3-Iminophenoxazine with Ammonia and AminesPhenazines and phenoxazines are formed in the reaction of 3-iminophenoxazine with amines.
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  • 89
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    Neue Reagenzien, XXXI. Synthese von (Iodmethyl)- und (Diiodmethyl)element-Verbindungen der Elemente Si, Ge, Sn, Pb (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 391-396 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: New Reagents, XXXI. Synthesis of (Iodomethyl)-and (Diiodomethyl)element Compounds of the Elements Si, Ge, Sn, PbVia Li—CH2—Hal or Li—CHHal2 (Hal = I, Br), respectively, the monohalides Ph3El—CH2—I (El = Si, Ge, Pb) and Ph3 Ge—CH2—Br have been obtained (49-74%) as well as the dihalides Ph3El—CHI2 (El = Si, Ge, Sn; 49-69%), Ph3Pb—CHI2 (9%), and Ph3Ge—CHBr2 (78%). These compounds are favourable starting materials for corresponding monolithium compounds. Some of them have found synthetic applications.
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  • 90
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    Kleine Ringe, 50. Ungewöhnliche Dimerisierung von Tri-tert-bytylcyclobutadien (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 409-412 
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    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Small Rings, 50. Unusual Dimerization of Tri-tert-butylcyclobutadieneThe dimerization of tri-tert-butylcyclobutadiene (2) does not lead to syn-dimer 4 but  -  as shown by a X-ray structure determination  -  via a two-step process to the unexpected anti-configurated dimer 5.
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  • 91
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    Diazadiene als Steuerliganden in der homogenen Katalyse, IX. Katalytische Cyclotetramerisierung von Propiolsäureestern (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 428-435 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Diazadienes as Controlling Ligands in Homogeneous Catalysis, IX Catalytic Cyclotetramerization of Propynoic EstersPropynoic esters HC≡C—CO2R 2 react at low temperature in cyclohexane in the presence of precatalysts of the type of diazadiene-nickel(0) complexes 3 and 4 or diazadiene-nickel-(η2-alkyne) complexes such as 5b to give exclusively or preponderantly cyclooctatetraene tetracarboxylic esters 7. From 1H and 13C NMR data and by chemical methods a 1,3,6,8-substitution pattern (symmetry C2) is established.
    Notes: Propiolsäureester HC≡C—CO2R 2 lassen sich bei niedriger Temperatur in Cyclohexan an Präkatalysatoren vom Typ der Diazadien-Nickel(0)-Komplexe 3 bzw. 4 oder an Diazadien-Nickel-(η2-Alkin)-Komplexen wie 5b vollständig oder überwiegend zu Cyclooctatetraen-tetracarbon-säureestern 7 umsetzen. Aus 1H- und 13C-NMR-Daten sowie mit chemischen Methoden ergibt sich ein 1,3,6,8-Substitutionsmuster (Symmetrie C2).
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    Palladium- und Platin(II)-Komplexe mit den Anionen von 6-Methyl-1,2,3-oxathiazin-4(3H)-on-2,2-dioxid und N-2-Pyrimidinylsulfanilamid (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 444-449 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Palladium and Platinum(II) Complexes with the Anions of 6-Methyl-1,2,3-oxathiazin-4(3H)-one 2,2-Dioxide and N-2-PyrimidinylsulfanilamideWith the title ligand L = 3 the complexes K2[trans-PtCl2L2] (1) and K2[ML4] (M = Pt,Pd) (2, 4) have been obtained. The anion 5 of sulfadiazine and (nBu3P)(CI)PdCl2Pd(Cl)(PnBu3) give a dinuclear ligand bridged complex 6. The compounds are characterized by their IR and 1H NMR spectra. The structure of 1 was determined by X-ray structure analysis.
    Notes: Mit dem Titelliganden L = 3 werden die Komplexe K2[trans-PtCl2L2] (1) und K2[ML4] (M = Pt, Pd) (2, 4) erhalten. Das Sulfadiazin-Anion (5) bildet mit (nBu3P)(Cl)PdCl2Pd(Cl)(PnBu3) einen zweikernigen ligandverbrückten Komplex 6. Die Verbindungen werden spektroskopisch (IR, 1H-NMR) charakterisiert; die Struktur von 1 wird durch eine Röntgenstrukturanalyse bestimmt.
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    Ein neuer Zugang zu Alkylthio(trifluoracetyl)furanen durch thermische [3 + 2]-Cycloadditionen neuer mesoionischer 1,3-Oxathiol-4-one an Alkine (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 785-795 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: A New Entry to Alkylthio(trifluoroacetyl)furans by Way of Thermal [3 + 2]Cycloaddition Reactions of New Mesoionic 1,3-Oxathiol-4-ones to AlkynesAs cyclic carbonyl ylides, the novel 2-alkylthio-5-trifluoroacetyl-1,3-oxathiolylium-4-olates of type 1a-d combine with dimethyl acetylenedicarboxylate across the 2,5-position with formation of non-isolable primary adducts, which release COS to give the furandicarboxylic diesters 3a-d. Methyl propiolate reacts with 1a-c to produce mixtures of the regioisomeric furancarboxylic esters 4a-c and 5a-c, whose main components 4a-c are isolable. On the other hand, the reactions of phenylacetylene, 1-diethylaminopropyne, or (Z)-1-methoxy-1-buten-3-yne with 1a proceed with regiospecific formation of the furan derivatives 6, 7, or 8, respectively. The observed regioselectivities are qualitatively discussed on the basis of MO-perturbation theory.
    Notes: Als cyclische Carbonyl-ylide nehmen die neuen 2-Alkylthio-5-trifluoracetyl-1,3-oxathiolylium-4-olate vom Typ 1a-d in 2,5-Stellung Acetylendicarbonsäure-dimethylester unter Bildung nicht-isolierbarer Primäraddukte auf, die unter COS-Abspaltung Furandicarbonester 3a-d liefern. Mit Propiolsäure-methylester reagiert 1a-c zu Gemischen aus den regioisomeren Furancarbonestern 4a-c und 5a-c, deren Hauptkomponenten 4a-c isolierbar sind. Dagegen vereinigen sich Phenylacetylen, 1-Diethylaminopropin bzw. (Z)-1-Methoxy-1-buten-3-in mit 1a regiospezifisch zu den Furan-Derivaten 6, 7 bzw. 8. Die beobachteten Regioselektivitäten werden qualitativ auf der Basis der MO-Störungstheorie diskutiert.
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    Electron donor-acceptor compounds, XXXVI. Quinones and quinhydrones of the [2.2]- and [3.3]metaparacyclophane series (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 796-813 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Elektron-Donor-Acceptor-Verbindungen, XXXVI Chinone und Chinhydrone der [2.2]- und [3.3]Metaparacyclophan-ReihenDie isomeren Chinhydrone 1 und 2 sowie das Bis(chinon) 6 der [2.2]Metaparacyclophan-Reihe wurden synthetisiert. Vorstufe dieser Verbindungen war das Tetramethoxy[2.2]metaparacyclophan 3, das über 4 und 5 dargestellt wurde. Röntgen-Strukturanalysen von 1, 3 und 6 werden im Hinblick auf die sterische Spannung dieser Moleküle und die Donor-Acceptor-Orientierung in 1 diskutiert. Charge-transfer-Absorptionen von 1 und 2 werden ebenso behandelt wie der Circulardichroismus von 1, das in Enantiomere getrennt werden konnte.  -  Auf analogem Wege wurden die isomeren Chinhydrone 13 und 14 sowie das Bis(chinon) 15 der [3.3]Metaparacyclophan-Reihe dargestellt. Der Unterschied in der sterischen Spannung zwischen den [3.3]- und [2.2]-Metaparacyclophan-Reihen wird auf der Grundlage der Röntgen-Strukturanalyse von 13 diskutiert. Charge-transfer-Absorptionen von 13 und 14 werden angegeben.
    Notes: The isomeric quinhydrones 1 and 2 as well as the bis(quinone) 6 of the [2.2]metaparacyclophane series were synthesized. Precursor of these products was the tetramethoxy[2.2]metaparacyclophane 3 which was prepared via 4 and 5. X-ray structure analyses of 1, 3 and 6 are discussed with regard to the steric strain in these molecules and the donor-acceptor orientation in 1. Charge-transfer absorptions of 1 and 2 are reported as well as circular dichroism of 1 which was separated into enantiomers.  -  Following an analogous route the isomeric quinhydrones 13 and 14 as well as the bis(quinone) 15 of the [3.3]metaparacyclophane series were prepared. The difference in steric strain of the [3.3]- in comparison to the [2.2]metaparacyclophane series is discussed on the basis of an X-ray structure analysis of 13. Charge-transfer absorptions of 13 and 14 are reported.
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    Disproval of claimed unusually stable primary ozonides of 1,4-dichloro-2-butenes (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 845-850 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Beweise gegen postulierte ungewöhnlich stabile Primärozonide von 1,4-Dichlor-2-butenenOzonolysen von cis- und trans-1,4-Dichlor-2-buten (1) in Methanol ergaben ca. äquimolare Anteile an 2-Chlor-1-methoxyethanol (6a) und 2-Chlor-1-methoxyethylhydroperoxid (7a) als Hauptprodukte sowie eine geringe Menge 2,2′-Dichlor-1-hydroxy-1′-methoxydiethylperoxid (8a). Ozonolyse von 1 in [D4]Methanol ergab die entsprechenden deuterierten Produkte 6c-8c. Die postulierte Existenz von ungewöhnlich stabilen Primärozoniden 2 wird widerlegt.
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    Organische Synthesen mit Übergangsmetallkomplexen, 10. Metalltemplate zur Synthese carbocyclischer Vier- und Sechsringe aus Isonitrilen und Carbenkomplexen (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 952-963 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Organic Syntheses with Transition Metal Complexes, 10. Metal Templates for the Syntheses of Carbocyclic Four- and Six-membered Rings from Isonitriles and Carbene ComplexesIsonitriles (R—NC, R = CH3, c-C6H11, tC4H9) react with carbene complexes (CO)5CrC(OCH3)R′ (R′ = CH3, C6H5) to give ketenimine complexes (CO)5Cr(R)N=C=C(OCH3)R′ 2a-f via insertion of the isonitrile into the M=C bond. The complexes 2 are isolated in crystalline form. On warming they dismutate to (CO)6Cr and (CO)4Cr complexes 3a-f of a 1,2-bis(imino)cyclobutane chelate ligand 4. The ligands 4 are generated in a template reaction by a hitherto unknown symmetrical [2 + 2]dimerisation of the ketenimines. 4 and the 1, 2-bis(hydroximino)cyclobutane 5 are obtained free of the metal by disengagement with H2O2/OH- or H2NOH, respectively. 3d, e easily isomerize to give bis(imino)tetrahydronaphthalenes 6d, e by expansion of the carbocyclic four- to the six-membered ring incorporating the phenyl group. Thermolysis of 6 leads to the formation of the 1,2-dihydronaphthaline derivative 7. The latter is also accessible in a one-pot synthesis from the carbene complex and the isonitrile without isolation of the intermediates 2, 3, and 6.
    Notes: Isonitrile (R — NC, R = CH3, c-C6H11, t-C4H9) reagieren mit Carbenkomplexen (CO)5CrC(OCH3)R′ (R′ = CH3, C6H5) unter Insertion der N = C- in die M = C-Bindung zu kristallin isolierbaren Keteniminkomplexen (CO)5Cr(R)N = C = C(OCH3)R′ 2a-f. Letztere sind sehr kondensations-freudig und dismutieren bei Abwesenheit eines Reaktionspartners zu (CO)6Cr und (CO)4Cr-Komplexen 3a-f, die ein 1,2-Bis(imino)cyclobutan 4 als Chelatligand enthalten. 4 bildet sich in einer Templatreaktion unter bisher unbekannter symmetrischer [2 + 2]-Dimerisierung des Keteniminliganden. Metallfreies 4 und ein davon abgeleitetes 1,2-Bis(hydroximino)cyclobutan 5 erhält man durch oxidative Zersetzung von 3 mit H2O2/OH- oder H2NOH. Die Bis(imino)cyclobutan-Komplexe 3d, e isomerisieren beim Erwärmen zu Bis(imino)tetrahydronaphthalin-Komplexen 6d, e durch Ringerweiterung des carbocyclischen Vier- zum Sechsring unter Einbeziehung des Aromaten. Die Thermolyse von 6e oder 6e′ gibt ein metallfreies 1,2-Dihydronaphthalin 7. Dieses kann in einer „Eintopfsynthese“ auch ohne Isolierung der Zwischenstufen 2, 3 und 6 direkt aus dem Carbenkomplex und dem Isonitril erhalten werden.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19851180313
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  • 97
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    Versuche zur Darstellung eines Alkinyldiazonium-Salzes (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 1008-1021 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Attempts to Prepare an Alkynyldiazonium SaltThe 2-bromo-1-chloroalkanal p-tosylhydrazones 11a, and b react with triethylamine as base to give the azoalkenes 12, of which (1-chloro-2-phenylethenyl)tosyldiazene (12b) is obtained as a crystalline material at room temperature. 12b reacts with SbCl5 at - 30 and - 70°C to form different diazonium salts, which are treated with nucleophiles such as methanol and water. The products obtained (Schemes 3 and 4) indicate the formation of the phenylethynyldiazonium salt 20, which is stable up to - 20°C. 20 adds nucleophiles like methanol or water as well as anisole at the C°C triple bond before releasing nitrogen.
    Notes: Die 2-Brom-1-chloralkanal-p-tosylhydrazone 11a und b reagieren mit Triethylamin als Base zu den Azoalkenen 12, von denen (1-Chlor-2-phenylethenyl)tosyldiazen (12b) als kristalline, bei Raumtemperatur stabile Verbindung erhalten wird. 12b reagiert mit SbCl5 bei - 30 und - 70°C zu verschiedenen Diazoniumsalzen, die mit nucleophilen Reaktionspartnern (Methanol und Wasser) umgesetzt werden. Die dabei erhaltenen Produkte (Schema 3 und 4) deuten auf die Entstehung des Phenylethinyldiazonioum-Salzes 20, das bis etwa - 20°C stabil ist. 20 addiert Nucleophile wie Methanol oder Wasser, aber auch Anisol an die C°C-Dreifachbindung, bevor eine Stickstoffabgabe erfolgt.
    Additional Material: 1 Tab.
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    URL: http://dx.doi.org/10.1002/cber.19851180317
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    Magnesium-acetylacetonat, Mg3[MeC(O)CHC(O)Me]6, und Magnesium-(diethoxyphosphinyl)acetonat, Mg3[(EtO)2P(O)CHC(O)Me]6, dreikernige Chelatkomplexe (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 3529-3534 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Magnesium Acetylacetonate, Mg3[MeC(O)CHC(O)Me]6, and Magnesium (Diethoxyphosphinyl)acetonate, Mg3[(EtO)2P(O)CHC(O)Me]6- Trinuclear Chelate ComplexesThe title compounds 1 and 2 have been investigated by X-ray structure analysis and found to be trimeric. Each Mg atom is coordinated by six O atoms with a distorted octahedral array. The bridging of the central Mg atom with the terminal ones is achieved by common O atoms of the carbonyl groups. Whereas the preparation of magnesium (diethoxyphosphinyl)acetonate (2) has been reported previously, magnesium acetylacetonate (1) has been obtained for the first time by dehydration of Mg(acac)2(H2O)2.
    Notes: Röntgenuntersuchungen ergaben für die Titelverbindungen 1 und 2 trimere Strukturen. Jedes Mg-Atom ist von sechs O-Atomen verzerrt oktaedrisch koordiniert. Die Verbrückung des zentralen Mg-Atoms mit den endständigen erfolgt durch gemeinsame O-Atome der Car-bonyl-Gruppen. Magnesium-(diethoxyphosphinyl)acetonat (2) wurde nach Literaturangaben hergestellt, die Darstellung von Magnesium-acetylacetonat (1) erfolgte erstmals durch Entwässerung von Mg(acac)2(H2O)2.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19851180909
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  • 99
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    Photolyse von 9-Azido-10-methyltriptycen. - Dimerisierung eines extrem gespannten Brückenkopfimins durch verschiedene Cycloadditionen (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 3535-3550 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Photolysis of 9-Azido-10-methyltriptycene. - Dimerization of a Severely Strained Bridgehead Imine via Distinct Cycloaddition RoutesIrradiation of a cyclohexane solution of the 9-azidotriptycene 1b affords molecular nitrogen and a mixture of products. By means of chromatography a dimer (S2-7), which is yellow in solution, and two colorless dimers (e.g. 3b and 5) of the intermediate bridgehead imine 2b are separated from this mixture. The structures of the photoproducts are elucidated by spectroscopic methods, particularly high field NMR. In addition, the structure 5 is proven by its rapid and quantitative photoisomerization to the colored dimer S2-7 the constitution 7 of which is confirmed by comparison with the anthrone anil 11 and hydrolysis to the (2-aminophenyl)anthrone 9. At room temperature rapid diastereotopomerization of the benzene rings of the 9,10-dihydroanthracene systems of S2-7 occurs via N-inversion (1H, 13C NMR). According to the proton spectrum in the absence of exchange ( - 60 °C), the colored product possesses S2 rather than C2 symmetry. The photoproducts are postulated to be derived from the initially formed azahomotriptycene 2b bearing a formal bridgehead CN double bond. This bridgehead imine first dimerizes to the isomeric 1,4-diradicals 13 and 14 which subsequently cyclize to the intermediate 15 and the [2 + 2] dimer 5, respectively. Photochemical [2 + 2]cycloelimination of 5 affords the dimer S2-7.
    Notes: Durch Bestrahlung des 9-Azidotriptycens 1b in Cyclohexan erhält man neben Stickstoff ein Gemisch, aus dem chromatographisch ein in Lösung gelbes Dimeres (S2-7) und zwei farblose Dimere (3b und 5) des intermediären Brückenkopfimins 2b isoliert werden. Die Strukturen dieser Photoprodukte werden auf spektroskopischem Weg, insbesondere mit Hilfe von Hochfeld-NMR-Spektren, aufgeklärt. Zusätzlich wird die Struktur 5 durch die rasche, quantitative Photoisomerisierung in das farbige Dimere S2-7 gesichert, dessen Konstitution 7 durch Vergleich mit dem Anthronanil 11 und Hydrolyse zum (2-Aminophenyl)anthron 9 bewiesen wird. Bei Raumtemperatur tritt rasche Diastereotopomerisierung der Benzolringe der 9,10-Dihydroanthracen-Systeme von S2-7 durch N-Inversion ein (1H-, 13C-NMR). Aufgrund des 1H-NMR-Spektrums bei Abwesenheit von raschem Austausch ( - 60°C) besitzt das farbige Produkt S2- und nicht C2-Symmetrie. Es wird angenommen, daß zunächst das Azahomotriptycen 2b mit einer formalen Brückenkopf-CN-Doppelbindung entsteht, das zu den rotationsisomeren 1,4-Diradikalen 13 und 14 dimerisiert, die zur Zwischenstufe 15 bzw. dem [2 + 2]-Dimeren 5 cyclisieren. Photochemische [2 + 2]-Cycloeliminierung von 5 ergibt das Dimere S2-7.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19851180910
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  • 100
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    Übergangsmetallkomplexe instabiler Ylide, VII. Synthese und Reaktivität von als Vertreter eines Ylid-Chelatkomplexes mit exocyclischer C =C-Doppelbindung (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 3560-3569 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Transition Metal Complexes of Instable Ylides, VII. Synthesis and Reactivity of as an Example of an Ylide Chelate Complex Containing an Exocyclic C =C Double BondThe sulfur ylide complex (CO)5Cr[CH2S(O)Me2] reacts with 1,1-bis(diphenylphosphino)-ethene (1) to yield the five-membered metalla-heterocycle 2 with a reactive exocyclic C =C double bond. To this double bond carbon-, hydrogen-, phosphorus-, and sulfur nucleophiles are easily added.
    Notes: Der Schwefelylidkomplex (CO)5Cr[CH2S(O)Me2] reagiert mit 1,1-Bis(diphenylphosphino)-ethen (1) zu dem fünfgliedrigen Metallacyclus 2, der eine reaktive exocyclische C =C-Doppelbindung aufweist. An diese werden Nucleophile mit C, H, P und S als Donoratomen glatt addiert.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19851180912
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