ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Aminomethylation  (1)
  • Crystal Structures  (1)
  • halogen compounds  (1)
  • 1995-1999  (3)
  • 1
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 1777-1785 
    ISSN: 0009-2940
    Keywords: Lithiation ; Aminomethylation ; Nitrogen heterocycles ; Diazasilaheterocycles ; Diazaphosphaheterocycles ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The aminals tetramethylmethylenediamine (TMMDA) la, dicyclohexyldimethylmethylenediamine (CMMDA) lb, and di-isopropyldimethylmethylenediamine (IMMDA) lc are doubly metalated by LitBu to give LiCH2N(R)CH2N(R)CH2Li [2a: R = Me, 2b: R = Cy (Cy = cyclohexyl), 2c: R = iPr], which precipitate out of pentane as highly pyrophoric substances. Deuteration confirms N-methyl metalation exclusively. A series of aminomethylation reactions were performed by means of the doubly lithiated aminals 2a-c. The reactions of 2a-c with monochlorosilanes yield the silylated species R′3SiCH2MN(R)CH2N(R)CH2SiR′3 (3a: R′= Me, R == Me; 3b: R′ == Me, R == Cy; 3c: R′= Me, R = iPr 4: R′= Ph, R = Me, see Scheme 2). The use of dichlorosilanes lead to six-membered heterocycles 6a-6d. 6a is transferred into a mono quarternary ammonium salt 7 by methylation with MeI. The spirocycle 8 is obtained from SiCl4 and two equivalents of 2a. Similarly, several substituted 1,3-diaza-5-phosphacyclohexanes 9a-e (R1 = Me, Ph, NPh2, NCy2, see Scheme 3) are synthesized by the reaction of dichlorophosphanes R1PC2, with 2a and 2b, respectively. Oxidation of 9d with sulfur yields 12a, which is characterized by X-ray structure determination.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 0947-6539
    Keywords: ab initio calculations ; crystal structure ; halogen compounds ; nitrides ; selenium compounds ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Se2NBr3, a planar molecule shaped liked dividers, was formed by the reaction of SeBr4 with N(SiMe3)3, which reduced the selenium to the trivalent state. Under the same conditions, Se2NCl5 was obtained by the reaction of SeCl4 with N(SiMe3)3, retaining the tetravalent state of selenium. The molecule is formed by two edge-sharing pseudotrigonal bipyramids with selenium as their central atoms. Se2NCl5 reacts with PPh4Cl to form the Se2NCl-6 ion by the addition of a Cl- ion to only one of the two selenium atoms, resulting in pseudooctahedral coordination of this atom. Ab initio calculations for all the compounds reported confirm the experimentally determined structures.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 0044-2313
    Keywords: Phosphorane Iminato Complexes of Sulfur ; Syntheses ; IR Spectra ; Crystal Structures ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Phosphorane Iminato Complexes of Sulfur. Syntheses and Crystal Structures of [O3SS(NPPh3)2] · CH3CN, [SO(NPPh3)2], and [SCl(NPMe3)2]ClThe title compounds have been prepared by the reaction of Me3SiNPPh3 with SO2 and SOCl2, respectively, and by the reaction of Me3SiNPMe3 with S2Cl2. They form colourless, moisture sensitive crystals, which were characterized by IR spectroscopy and by crystal structure determinations.[O3SS((NPPh3)2)] · CH3CN: Space group Pca21, Z = 4, structure solution with 4016 observed unique reflections, R = 0.050. Lattice dimensions at -60°C: a = 1865.1, b = 1168.4, c = 1569.0 pm. The compound has a zwitterionic structure with a S—S bond length of 218.2 pm and bond lengths S—N of 161.2 and P—N of 160.1 pm.[SO(NPPh3)2]: Space group P21/c, Z = 4, structure solution with 2854 observed unique reflections, R = 0.113. Lattice dimensions at -50°C: a = 1173.1, b = 1585.6, c = 1619.2 pm, b̃ = 98.13°. The compound forms monomeric molecules, in which the positions of S and N atoms are disordered in two positions. The bond lengths are S—N 166 pm and P—N 163 pm in average.[SCl(NPMe3)2]Cl: Space group P1, Z = 2, structure solution with 2416 observed unique reflections, R = 0.038. Lattice dimensions at 20°C: a = 613.2, b = 1030.3, c = 1111.4 pm, α = 88.48°, b̃ = 88.01°, γ = 83.10°. The compound forms ions [SCl(NPMe3)2]+ and Cl-. In the cation the sulfur atom is φ-tetrahedrally coordinated with a long S—Cl distance of 246.9 pm and bond lengths S—N of 155.3 pm and P—N of 164.3 pm in average.
    Notes: Die Titelverbindungen entstehen durch Umsetzung von Me3SiNPPh3 mit Schwefeldioxid bzw. mit Thionylchlorid und von Me3SiNPMe3 mit Dischwefeldichlorid als farblose, feuchtigkeitsempfindliche Kristalle, die wir durch die IR-Spektren und durch Kristallstrukturanalysen charakterisiert haben.[O3SS(NPPh3)2)] · CH3CN: Raumgruppe Pca21, Z = 4, Strukturlösung mit 4016 unabhängigen beobachteten Reflexen, R = 0,050. Gitterabmessungen bei -60°C: a = 1865,1; b = 1168,4; c = 1569,0 pm. Die Verbindung hat eine zwitterionische Struktur mit einer S—S-Bindungslänge von 218,2 pm und Abständen S—N von 161,2 pm und P—N von 160,1 pm.[SO(NPPh3)2]: Raumgruppe P21/c, Z = 4, Strukturbestimmung mit 2854 unabhängigen beobachteten Reflexen, R = 0,113. Gitterabmessungen bei -50°C: a = 1173,1; b = 1585,6; c = 1619,2 pm, b̃ = 98,13°. Die Verbindung hat eine monomere Molekülstruktur, deren S- und N-Atomlagen in zwei Positionen fehlgeordnet sind. Die Bindungslängen betragen im Mittel für S—N 166 pm und für P—N 163 pm.[SCl(NPMe3)2]Cl: Raumgruppe P1, Z = 2, Strukturlösung mit 2416 unabhängigen beobachteten Reflexen, R = 0,038. Gitterabmessungen bei 20°C: a = 613,2; b = 1030,3; c = 1111,4 pm, α = 88,48°; b̃ = 88,01°; γ = 83,10°. Die Verbindung besteht aus Ionen [SCl(NPMe3]2+ und Cl-. Im Kation ist das Schwefelatom φ-tetraedrisch koordiniert mit einem S—Cl-Abstand von 246,9 pm und mittleren Bindungslängen S—N von 155,3 pm und P—N von 164,3 pm.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...