Syntheses and Reactivity of Stannyloligosilanes. 2. Branched Stannyloligosilanes
摘要:
Branched tri(stannyl)tetrasilanes MeSi[SiMe2SnR2R'](3) (2, R = R' = Ph; 3, R = R' = Me; 5, R = t-Bu, R' = H) were synthesized by the reaction of alkali metal tri- or diorganostannides with methyltris(fluorodimethylsilyl)silane (1) or methyltris(chlorodimethylsilyl)silane (4) or by reacting triphenylchlorostannane with 1 in the presence of magnesium. Methyltris[(hydridodi-tert-butylstannyl)dimethylsiyl]silane (5) was halogenated at the tin atom by treatment with CHCl3 or CHBr3. Surprisingly, the reaction of 5 with 3 equiv of lithium diisopropylamide (LDA) resulted in the formation of the five-membered ring 10 (2-dimethylsilyl-1,1,2,3,3-pentamethyl-4,4,5,5-tetra-tert-butyl-1,2,3-trisila-4,5-distannacyclopentane) with a bridging Sn-Sn unit. Reacting 5 with triethylamine or aminostannanes resulted in the formation of 2-dimethylsilyl-1,2,3,3-pentamethyl-4,4,5,6,6-penta-tert-butyl-1,2,3-trisila-4,5,6-tristannacyclohexane (14). The solid-state structures of 5 and 14b were determined by X-ray crystallography.
New Cyclic and Polycyclic Ring Systems Containing Group 14 (Si, Ge, Sn) and 16 (S, Se, Te) Elements
作者:Uwe Herzog、Uwe Böhme、Gerd Rheinwald
DOI:10.1080/10426500108546568
日期:2001.1.1
The reactions of Me2MCl2 (M = Si, Ge, Sn), Si2Me4Cl2, Si2Me2Cl3, Si2Me2Cl4 and CH2(SiCl2Me)2, and suitable mixtures thereof, with H2S / NEt3 and Li2E (E = Se, Te) have been investigated and lead to a variety of new group 14 chalcogenide systems.
Cyclosilyl alkali compounds are universal reagents for the preparation of polycyclic silanes. Undecamethylcyclohexasilanyl potassium reacts with different chlorosilanes yielding three new methylated polycyclic silanes, which have been isolated and characterized.
Reaction of the SiCl bond with trialkyl orthoformates preparation of alkoxy-substituted silanes
作者:U Herzog、N Schulze、K Trommer、G Roewer
DOI:10.1016/s0022-328x(97)00204-0
日期:1997.11
Trialkyl orthoformates in the presence of aluminiumchloride represent quite useful reagents to generate silicon alkoxides from chlorosilanes. 3-Cyanopropyltrichlorosilane and 2-[(2-trichlorosily)ethyl]-pyridine give the triethoxy compounds 3-cyanopropyltriethoxysilane and 2-[(2-triethoxysilyl)ethyl]-pyridine respectively. Via this route, in methylchlorooligosilanes a partial or complete exchange of
Novel double-cored oligosilane dendrimers—conformational dependence of the UV absorption spectra
作者:C. Krempner、M. Köckerling、C. Mamat
DOI:10.1039/b515562b
日期:——
The novel double-cored oligosilane dendrimers [Me(Me3Si)2SiâMe2Si]2SiMeâSiMe2}2 (4) and [Me(Me3Si)2SiâMe2Si]2SiMe}2 (5) have been shown to display unusual UV absorption behaviour as a function of conformation and steric interaction in the longest oligosilane chains.
A significant enhancement of the intensity of the room temperature photoluminescence in the visible region by two orders of magnitude is observed upon introducing oxygen containing functional groups into well-defined oligosilane dendrimers.