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  • Wiley-Blackwell  (16)
  • Schweizerbart  (1)
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  • 1
    Electronic Resource
    Electronic Resource
    Coconut-fiber-reinforced thermosetting plasticsCorrected proofs lost in transit. (1985)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 30 (1985), S. 1827-1836 
    Details
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Thermosetting plastic composites have been prepared with phenol-formaldehyde resins as well as unsaturated polyesters as binders and coconut hair as fibrous reinforcement. Using resole-type phenol-formaldehyde resins, the effect of coconut fiber pretreatment by NaOH, the precondensation time of the impregnated fibrous press material, the resin-fiber ratio, and pressing parameters have been studied. Especially advantageous press-material has been obtained using 60-65 wt % linear novolac type phenol-formaldehyde resin as binder and 35-40 wt % of coconut hair. Applying unsaturated polyester (UP) as binder, BMC (bulk molding compound)-type press material can be prepared using coconut fiber reinforcement instead of glass fibers. To achieve better coupling between coconut fiber and UP matrix, coconut fiber was pretreated by NaOH and/or gamma-preirradiation. It has been found that in glass-fiber-reinforced UP press materials a significant part of glass fiber could be changed for short-cut coconut fiber.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1985.070300504
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  • 2
    Electronic Resource
    Electronic Resource
    Synthese, Charakterisierung und Struktur von P7(t-Bu3Si)3 („Tris(supersilyl)heptaphosphan(3)“)Professor Hartmut Bärnighausen zum 60. Geburtstage gewidmet (1993)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 619 (1993), S. 453-460 
    Details
    ISSN: 0044-2313
    Keywords: Tris(tri-tert-butylsilyl)heptaphosphonortricyclane P7(t-Bu3Si)3 ; synthesis ; 31P{1H} NMR data ; crystal structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis, Characterization, and Structure of P7(t-Bu3Si)3 („Tris(supersilyl)heptaphosphane(3)“Tris(tri-tert-butylsilyl)heptaphosphanortricyclane P7(t-Bu3Si)3 1 is obtained from the reaction of (t-Bu)3Si—Si(t-Bu)3 with white phosphorus and forms colorless to pale yellow thermostable crystals. 1 is identified by the complete analysis of its 31P{1H} NMR spectrum (A[MX]3 spin system) as well as by a single crystal structure determination (space group Pca21, a = 170.76(2)pm, b = 131.14(3)pm, c = 426.61(5)pm, α = β = γ= 90°, Z = 8 formula units in the elementary cell). The steric demand of the (t-Bu)3Si-Groups causes an increase of the exocyclic bond angles at the equatorial phosphorus atoms Pe, while it does not particularly influence the P7-skeleton. Chlorine (r.t.) and bromine (70°C) degrade the P7-cage of 1 with formation of PX3 and (t-Bu)3SiX (X = Cl, Br).
    Notes: Tris(tri-tert-butylsilyl)-heptaphosphanortricyclan P7(t-Bu3Si)3 1 entsteht durch Umsetzung von (t-Bu)3Si—Si(t-Bu)3 mit weißem Phosphor und bildet farblose bis blaßgelbe thermostabile Kristalle. Die Identität von 1 wird durch die vollständige Analyse des 31P{1H}-NMR-Spektrums (A[MX]3-Spinsystem) sowie durch eine Kristallstrukturbestimmung belegt. 1 kristallisiert in der Raumgruppe Pca21 mit Z = 8 Formeleinheiten; a = 170,76(2)pm, b = 131,14(3)pm, c = 426,61(5)pm, α = β = γ= 90°. Der erhöhte Raumbedarf der (t-Bu)3Si-Gruppen führt zu einer Aufweitung der exocyclischen Bindungswinkel an den äquatorialen Phosphoratomen Pe ohne das P7-Gerüst besonders zu beeinflußen. Chlor (Raumtemperatur) und Brom (70°C) bauen den P7-Käfig von 1 unter Bildung von PX3 und (t-Bu)3SiX (X = Cl, Br,) ab.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19936190305
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  • 3
    Electronic Resource
    Electronic Resource
    Die Kristallstruktur des tBu2P—P=P(Br)tBu2 (1994)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 620 (1994), S. 1818-1820 
    Details
    ISSN: 0044-2313
    Keywords: Crystal structure of tBu2P—P=P(Br)tBu2 ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The Crystal Structure of tBu2P—P=P(Br)tBu2tBu2P—P=P(Br)tBu2 1 crystallizes in the monoclinic space group P21/c with a = 2 888.9(3), b = 972.16(10), c = 1 534.04(14) pm, β = 105.129(8)° and 8 formula units in the unit cell. The two independent P3-units in 1 form angles of 105.77° or 105.98°, resp. One P—P distance (220,4 pm) corresponds to a single bond, the other one (207.9 pm) to a double bond.
    Notes: tBu2P—P=P(Br)tBu2 1 kristallisiert monoklin in der Raumgruppe P21/c mit a = 2 888,9(3), b = 972,16(10), c = 1 534,04(14) pm, β = 105,129(8)° und 8 Formeleinheiten in der Elementarzelle. Die beiden unabhängigen P3-Einheiten in 1 sind gewinkelt (105,77° bzw. 105,98°). Die P—P-Abstände entsprechen mit 220,4 pm einer Einfachbindung bzw. mit 207,9 pm einer Doppelbindung.
    Additional Material: 1 Ill.
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    URL: http://dx.doi.org/10.1002/zaac.19946201026
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  • 4
    Electronic Resource
    Electronic Resource
    Komplexchemie P-reicher Phosphane und Silylphosphane. XIV. Phosphinophosphiniden tBu2P—P als Ligand in den Pt-Komplexen [η2-{tBu2P—P}Pt(PPh3)2] und [η2-{tBu2P—P}Pt(PEtPh2)2] (1997)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 623 (1997), S. 1917-1924 
    Details
    ISSN: 0044-2313
    Keywords: Platinum complexes, tBu2P—P ; [η2-{tBu2P—P}Pt(PPh3)2] ; [η2-{tBu2P—P}Pt(PEtPh2)2] ; 1H-13C-, 31P-NMR Spectra ; Crystal Structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Coordination Chemistry of P-rich Phosphanes and Silylphasphanes. XIV. The Phosphinophosphinidene tBu2P—P as a Ligand in the Pt Complexes [η2-{tBu2P—P}Pt(PPh3)2] and [η2-{tBu2P—P}Pt(PEtPh2)2][η2-{tBu2P—P}Pt(PPh3)2 1 and [η2-{tBu2P—P}Pt(PEtPh2)2] 2 are the first complex compounds of tBu2P—P 5. They are formed in the reaction of tBu2P—P = P(Me)tBu2 3 with [η2-{H2C = CH2}Pt(PPh3)2] 6 or [η2-{H2C = CH2}Pt(PEtPh2)2] 7, respectively. Compound 1 is less stable than 2 and reacts on to [η2-{tBu2P—P} Pt(PPh3)(PtBu2Me)] 10 with the coincidently formed tBu2PMe. The molecular structures of 1 and 2 were derived from their 1H and 31P-NMR spectra, 2 was additionally characterized by a X ray structure determination. 2 crystallizes in the monoclinic space group P21/n with a = 1222.36(7) pm, b = 1770.7(1) pm, c = 1729.7(1) pm, β = 108.653(6)°.
    Notes: [η2-{tBu2P—P}Pt(PPh3)2] 1 und [η2-{t Bu2P—P}Pt(PEtPh2)2] 2 sind die ersten Komplexverbindungen des tBu2P—P 5. Sie entstehen bei der Umsetzung von tBu2P—P = P(Me)tBu2 3 mit [η2-{H2C=CH2}Pt(PPh3)2] 6 bzw. [η2-{H2C = CH2}Pt(PEtPh2)2] 7 unter Abspaltung von tBu2PMe. Verbindung 2 ist beständiger als 1. Mit tBu2PMe bildet 1 das [η2-{tBu2P—P} Pt(PPh3)(PtBu2Mc)] 10. Bei der Umsetzung von 6 mit 3 entsteht ebenfalls 10, weil das bei der Bildung von 1 freiwerdende tBu2PMe mit 1 weiterreagiert. Die Strukturen von 1 und 2 sind über ihre 1H- und 31P-NMR-Spektren, die von 2 zusätzlich durch eine Röntgenstrukturanalyse gesichert. 2 kristallisiert monoklin in P21/n mit a = 1222,36(7) pm, b = 1770,1(1) pm, c = 1729,7(1) pm, β = 108,653(6)°.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19976231216
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  • 5
    Electronic Resource
    Electronic Resource
    Die Bildung von [(tBu)2P]2P—P[P(tBu)2]2 aus LiP[P(tBu)2]2 und 1,2-Dibromethan. Die Thermolyse von tBu2P—P=P(Br)tBu2Professor O. J. Scherer zum 60. Geburtstage gewidmet (1994)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 620 (1994), S. 1-3 
    Details
    ISSN: 0044-2313
    Keywords: Formation of [(tBu2P)2P]2 from LiP[P(tBu)2]2 and 1,2-dibromethane ; pyrolysis of tBu2P—P=P(Br)tBu2 ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: [(tBu)2P]2P—P[P(tBu)2]2 from LiP[P(tBu)2]2 and 1,2-Dibromomethane. Pyrolysis of tBu2P—P=P(Br)tBu2All products of the reaction of [tBu2P]2PLi 1 with 1,2-dibromoethane 2 were investigated. Already at -70°C tBu2P—P=P(Br)tBu2 3 as main product and [tBu2P]2PBr 4 are formed. Only with an excess of 1 also [tBu2P]P—P[P(tBu)2]2 5 is obtained.Warming of a pure solution of 3 in toluene from -70°C to -30°C leads to 4, and at 20°C tBu2PBr and the cyclophosphanes P4[P(tBu)2]4 and P3[P(tBu)2]3 are observed. 5 does not result from 3, it's rather a byproduct from the reaction of 1 with 4. Also the ylide 3 and 1 yields 5.
    Notes: Es werden alle Reaktionsprodukte der Umsetzung von [tBu2P]2PLi 1 und 1,2-Dibromethan 2 aufgeklärt. Aus 1 und 2 bilden sich bereits bei -70°C tBu2P—P=P(Br)tBu2 3 (Hauptprodukt) und [tBu2P]2PBr 4. Nur bei einem Überschuß an 1 entsteht auch [(tBu)2P]2P—P · [P(tBu)2]2 5. In einer reinen Lösung von 3 (Toluol, -70°C) bilden sich um -30°C 4, um 20°C tBu2PBr und die Cyclophosphane P4[P(tBu)2]4, P3[P(tBu)2]3. 5 entsteht nicht aus 3, sondern immer als Nebenprodukt der Umsetzung von 1 mit 4. Das Ylid 3 bildet mit 1 ebenfalls Verbindung 5.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19946200102
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  • 6
    Electronic Resource
    Electronic Resource
    Komplexchemie P-reicher Phosphane und Silylphosphane. XII. Bildung und Struktur von Li(THF)2[η2-(tBu2P)2P], Li(TMEDA)[η2-(tBu2P)2P], Li(THF)2[η2-(iPr2P)2P], Li(THF)2[η2-(Et2N)2P—P—PtBu2], Li(THF)2[η2-(tBu2P—P—PiPr2] und (tBu2P)2P—SiMe3Professor Kurt Dehnicke zum 65. Geburtstag gewidmet (1996)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 622 (1996), S. 1564-1572 
    Details
    ISSN: 0044-2313
    Keywords: Li(THF)2[η2-(tBu2P)2P] ; Li(TMEDA)[η2-(tBu2P)2P] ; Li(THF)2[η2-(iPr2P)2P] ; Li(THF)2[η2-(Et2N)2P—P—PtBu2] ; Li(THF)2[η2-(tBu2P—P—PiPr2)] ; (tBu2P)2P—SiMe3 ; crystal structures ; 1H, 31P, 7Li-NMR spectra ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Formation and Structure of Li(THF)2[η2-(tBu2P)2P], Li(TMEDA)[η2-(tBu2P)2P], Li(THF)2[η2-(iPr2P)2P], Li(THF)2[η2-(Et2N)2P—P—PtBu2], Li(THF)2[η2-(tBu2P—P—PiPr2] and (tBu2P)2P—SiMe3The formation and crystal structures of the compounds (tBu2P)2P—SiMe3 1, Li(THF)2[η2-(tBu2P)2P] 2, Li(TMEDA)[η2-(tBu2P)2P] 3, Li(THF)2[η2-(iPr2P)2P] 4, Li(THF)2[η2-(Et2N)2P—P—PtBu2] 5 and Li(THF)2[η2-(tBu2P—P—PiPr2)] 6 are reported. Compounds 3-6 are formed by reacting the corresponding silylated triphosphanes with nBuLi: 2 and 3 result from (tBu2P)2P—SiMe3 1, 4 from (iPrP)2P—SiMe3, 5 from (Et2N)2P—P(SiMe3)—PtBu2 and 6 from tBu2P—P(SiMe3)—PiPr2. 1 crystallizes in the orthorhombic space group P212121 (no. 19) with a = 910.87(7) pm, b = 1132.5(1) pm, c = 2373.5(2) pm (determined at 90 K). The structure determination of 2 was performed at 293 K and 200 K, respectively. 2 crystallizes in the monoclinic space group P21/n (no. 14) with a = 1069.7(3) pm, b = 1802.5(3) pm, c = 1604.0(7) pm, β = 98.11(2)° (200 K); 3 also in P21/n (no. 14) with a = 904.3(2) pm, b = 1936.4(5) pm, c = 1653.2(3) pm, β = 94.52(1)° (200 K). 4 crystallizes monoclinically in C2/c (no. 15) with a = 1650.0(5) pm, b = 945.6(3) pm, c = 1779.8(5) pm, β = 108.81(2)° (200 K); 5 in P21/n (no. 14) with a = 939.4(5) pm, b = 1736.8(6) pm, c = 1943.3(7) pm, β = 98.17(4)° (200 K). All compounds contain Z = 4 molecules in the unit cell.The 1H, 31P and 7Li NMR spectra of 2-6 are discussed.
    Notes: Es wird über die Verbindungen (tBu2P)2P—SiMe3 1, Li(THF)2[η2-(tBu2P)2P] 2, Li(TMEDA) · [η2-(tBu2P)2P] 3, Li(THF)2[η2-(iPr2P)2P] 4, Li(THF)2[η2-(Et2N)2P—P—PtBu2] 5 und Li(THF)2[η2-(tBu2P—P—PiPr2)] 6 berichtet. Letztere bilden sich durch Umsetzung der entsprechenden silylierten Triphosphane mit nBuLi: 2 und 3 aus (tBu2P)2P—SiMe3 1, 4 aus (iPr2P)2P—SiMe3, 5 aus (Et2N)2—P · (SiMe3)—PtBu2, 6 aus tBu2P—P(SiMe3)—PiPr2.1 kristallisiert orthorhombisch in P212121 (Nr. 19) mit a = 910,87(7) pm, b = 1132,5(1) pm, c = 2373,5(2) pm (bei 90 K bestimmt). Die Strukturbestimmung von 2 erfolgte bei 293 K und 200 K. 2 kristallisiert monoklin in P21/n (Nr. 14) mit a = 1069,7(3) pm, b = 1802,5(3) pm, c = 1604,0(7) pm, β = 98,11(2)° (200 K), 3 ebenfalls in P21/n (Nr. 14) mit a = 904,3(2) pm, b = 1936,4(5) pm, c = 1653,2(3) pm, β = 94,52(1)° (200 K). 4 kristallisiert monoklin in C2/c (Nr. 15) mit a = 1650,0(5) pm, b = 945,6(3) pm, c = 1779,8(5) pm, β = 108,81(2)° (200K), 5 in P21/n (Nr. 14) mit a = 939,4(5) pm, b = 1736,8(6) pm, c = 1943,3(7) pm, β = 98,17(4)° (200 K). Alle fünf Verbindungen enthalten jeweils vier Formeleinheiten in der Elementarzelle.Es wird über die Untersuchung der 1H-, 31P- und 7Li-NMR-Spektren der Verbindungen 2-6 berichtet.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19966220920
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  • 7
    Electronic Resource
    Electronic Resource
    tBu2P—P=P(X)tBu2-Ylide (X = Cl, Br, I) durch Halogenierung von [tBu2P]2P—SiMe3 (1994)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 620 (1994), S. 1364-1366 
    Details
    ISSN: 0044-2313
    Keywords: Halogenation of [tBu2P]2P—SiMe3, tBu2P—P=P(X)tBu2 Ylide (X = Cl, Br, I) ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: tBu2P—P=P(X)tBu2 Ylides (X = Cl, Br, I) by Halogenation of [tBu2P]2P—SiMe3[tBu2P]2P—SiMe3 1 with halogenating agents as Br2, I2, Br-succinimide, CCl4, CBr4, CI4 or C2Cl6 via cleavage of the Si—P bond in 1 produces the ylides tBu2P—P=P(X)tBu2 (X = Cl, Br, I). This proceeds independent from the formerly known pathway - [tBu2P]2PLi + 1,2-dibromoethane - and shows that the Li-phosphide must not be present as a necessary requirement for the formation of ylides.
    Notes: [tBu2P]2P—SiMe3 1 reagiert mit Halogenierungsmitteln (Br2, I2, Bromsuccinimid, CCl4, CBr4, CI4, C2Cl6) über die Spaltung der Si—P-Bindung in 1 zu den Yliden tBu2P—P=P(X)tBu2 (X = Cl, Br, I). Dieser Weg ist unabhängig von dem bisher bekannten - [tBu2P]2PLi + 1,2-Dibromethan [1] - und zeigt, daß das Li-Phosphid nicht eine unabdingbare Voraussetzung für die Ylidbildung darstellt.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19946200806
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  • 8
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    Electronic Resource
    Reaktionen des tBu(Me3Si)P—P(Li)—P(tBu)2 mit CH3Cl und 1,2-Dibromethan (1994)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 620 (1994), S. 1367-1368 
    Details
    ISSN: 0044-2313
    Keywords: tBu(Me3Si)P—P=P(Me)tBu2, tBu(Me3Si)P—P(Br)—P(tBu)2, tBu(Me3Si)P—P=P(Br)tBu2, {tBuP—P[P(tBu)2]}2 from tBu(Me3Si)P—PLi—P(tBu)2 with MeCl or 1,2-Dibromoethane ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reactions of tBu(Me3Si)P—P(Li)—P(tBu)2 with CH3Cl and 1,2-DibromoethanetBu(Me3Si)P—P(Li)—P(tBu)2 · 0.95 THF 1 with CH3Cl (-70°C) yields tBu(Me3Si)P—P = P(Me)(tBu)2 2 at -70°C, with 1,2-Dibromoethane tBu(Me3Si)P—PBr—P(tBu)2 3 (main product) and tBu(Me3Si)P—P=P(Br)tBu2 4. 3 eliminates Me3SiBr yielding the cyclotetraphosphane {tBuP—P[P(tBu)2]}2 5.
    Notes: tBu(Me3Si)P—P(Li)—P(tBu)2 · 0,95 THF 1 bildet mit CH3Cl bei -70°C das Ylid tBu(Me3Si)P—P=P(Me)(tBu)2 2, mit 1,2-Dibromethan tBu(Me3Si)P—PBr—P(tBu)2 3 (Hauptprodukt), sowie tBu(Me3Si)P—P=P(Br)tBu2 4. Aus 3 entsteht unter Abspaltung von Me3SiBr das Cyclotetraphosphan {tBuP—P[P(tBu)2]}2 5.
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    URL: http://dx.doi.org/10.1002/zaac.19946200807
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  • 9
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    Electronic Resource
    [iPr2P]2P—SiMe3 und [iPr2P]2PLi - Synthese und Reaktionen Struktur des [iPr2P]2P—P[PiPr2]2 (1994)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 620 (1994), S. 1369-1374 
    Details
    ISSN: 0044-2313
    Keywords: Synthesis of [iPr2P]2P—SiMe3 1 and [iPr2P]2PLi 2. Reactions of 1 with CBr4, of 2 with 1,2-dibromoethane, and MeCl, yielding iPr2P—P=P(Br)iPr2, [iPrP]2P—P[PiPr2]2, iPr2P—P=P(Me)iPr2, crystal structure of Tetrakis(di-isopropyl-phosphino)diphosphane ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: [iPr2P]2P—SiMe3 and [iPr2P]2PLi - Synthesis and Reactions Structure of [iPr2P]2P—P[PiPr2]2[iPr2P]2P—SiMe3 1 and [iPr2P]2PLi 2 were prepared to investigate the influence of the bulky alkyl groups on formation and properties of the ylides R2P—P=P(X)R2 (R = iPr, tBu; X = Br, Me) in reactions of 1 with CBr4 and of 2 with 1,2-dibromoethane or MeCl, resp. Compared to the iPr groups the tBu groups favour the formation of ylides. With CBr4 1 forms iPr2P—P=P(Br)iPr2 5 just as a minor product which decomposes already below -30°C. With 1,2-dibromoethane 2 yields only traces of 5 but [iPr2P]P—P[P(iPr)2]2 7 as main product. With MeCl 2 gives iPrP—P=P(Me)iPr2 9 and [iPr2P]2PMe 10 in a molar ratio of 1:1. 9 is considerably more stable than 5. 7 crystallizes triclinic in the space group P1 (No. 2) with a = 10.813 Å, b = 11.967 Å, c = 15.362 Å, α = 67.90°, β = 71.36°, γ = 64.11° and two formula units in the unit cell.
    Notes: [iPr2P]2P—SiMe3 1 und [iPr2P]2PLi 2 wurden synthetisiert. Die Umsetzungen von 1 mit CBr4 und von 2 mit 1,2-Dibromethan bzw. MeCl ermöglichen einen Vergleich des Einflusses der iPr- bzw. tBu-Gruppen auf Bildung und Eigenschaften der Ylide R2P—P=P(X)R2 (R = iPr, tBu; X = Br, Me) bei analogen Reaktionen.Die tBu-Gruppe begünstigt gegenüber der iPr-Gruppe die Ylidbildung. 1 bildet mit CBr4 das iPr2P—P=P(Br)iPr2 5 als Nebenprodukt, das sich schon unterhalb -30°C zersetzt. 2 bildet mit 1,2-Dibromethan das Ylid 5 nur in Spuren, aber [(iPr)2P]2P—P[P(iPr)2]2 7 als Hauptprodukt. 2 reagiert mit MeCl zum iPr2P—P=P(Me)iPr2 9 und [iPr2P]2PMe 10 im Molverhältnis 1:1. 9 ist erheblich beständiger als 5. 7 kristallisiert triklin in P1 (Nr. 2) mit a = 10,813 Å, b = 11,967 Å, c = 15,362 Å, α = 67,90°, β = 71,36°, γ = 64,11°. Die Elementarzelle enthält zwei Formeleinheiten.
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    URL: http://dx.doi.org/10.1002/zaac.19946200808
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  • 10
    Electronic Resource
    Electronic Resource
    Reaktionen von (tBu)2P—P=P(Br)tBu2 mit LiP(SiMe3)2, LiPMe2 und LiMe, LitBu, LinBu (1994)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 620 (1994), S. 4-7 
    Details
    ISSN: 0044-2313
    Keywords: Reactions of (tBu)2P—P=P(Br)tBu2 with LiPR2 (R = SiMe3, Me) or LiMe ; diphosphanes P2R2 (R = SiMe3, Me) ; isotetraphosphanes P[P(tBu)2]2PR2, tBu2P—P=P(Me)tBu2 ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reactions of (tBu)2P—P=P(Br)tBu2 with LiP(SiMe3)2, LiPMe2 and LiMe, LitBu and LinBuThe reactions of (tBu)2P—P=P(Br)tBu2 1 with LiP(SiMe3)2 2 yield (Me3Si)2P—P(SiMe3)2 4 and P[P(tBu)2]2P(SiMe3)2 5, whereas 1 with LiPMe2 2 yields P2Me4 6 and P[(tBu)2]2PMe2 7. 1 with LiMe yields the ylid tBu2P—P=P(Me)tBu2 (main product) and [tBu2P]2PMe 15.In the reaction of 1 with tBuLi [tBu2P]2PH 11 is the main product and also tBuP—P=P(R)tBu2 21 is formed. The reaction of 1 with nBuLi leads to [tBu2P]2PnBu 17 (main product) and tBu2P—P=P(nBu)tBu2 22 (secondary product).
    Notes: Die Umsetzung von (tBu)2P—P=P(Br)tBu2 1 mit LiP(SiMe3)2 2 führt zu den Verbindungen (Me3Si)2P—P(SiMe3)2 4 und P[P(tBu)2]2P(SiMe3)2 5, mit LiPMe2 2 entsprechend zu P2Me4 6 und P[P(tBu)2]2PMe2 7. Mit LiMe bildet 1 das Ylid tBu2P—P=P(Me)tBu2 14 (Hauptprodukt) neben [tBu2P]2PMe 15. Bei Umsetzung von 1 mit tBuLi is [tBu2P]2PH 11 Hauptprodukt, und es bildet sich tBu2P—P=P(R)tBu2 21. Die Umsetzung von 1 mit nBuLi führt zum [tBu2P]2PnBu 17 (Hauptprodukt) neben tBu2P—P=P(nBu)tBu2 22. Der Verlauf der Umsetzungen wird beschrieben.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19946200103
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