65105-84-2Relevant articles and documents
Reactions of symmetrical and unsymmetrical disilanes in the presence of Cp2MCl2/nBuli ( M = Ti, Zr, Hf)
Corey,Rooney
, p. 75 - 91 (1996)
The reactions of disilanes with catalytic quantities of Cp2MCl2/n BuLi (M = Ti, Zr) and cis-cyclooctene in a disilane/cyclooctene/metal ratio of approximately 30 : ≥ 30: 1 exhibited rapid formation of monosilanes and trisilanes. The product distributions produced from H(PhMeSi)2H, H(BuMeSi)2H (symmetrical disilanes) and from HPh2SiSiPhMeH, HPhMeSiSiMe2H, HPhMeSiSiPrMeH and HPh2SiSiPhH2 (unsymmetrical disilanes) were determined by GCMS in all cases and the trisilanes from HPh2SiSiPhMeH and HPhMeSiSiMe2 H were isolated and characterized spectroscopically. Major and minor isomers of Ph4Me2Si3H2 and Ph5MeSi3H2 (formed from HPh2SiSiPhMeH) and of PhMe5Si3H2 and Ph2Me4Si3H2 (formed from HPhMeSiSiMe2H) were identified. Analysis of the product distribution in these reactions indicated that both Si-Si bond cleavage and Si-H dehydrocoupling of the starting disilane occurs. Rationalization of the product distributions and apparent isomer preferences through both σ-bond metathesis steps and metal silylene intermediates is presented. The rapid reaction of the Si-Si bond in H(SiPhMe)χH was found to be characteristic of the disilane and occurred only to a minor extent in the trisilane and was absent in the tetrasilane.
Conversion of hydrosilanes to alkoxysilanes catalyzed by Cp2TiCl2/nBuLi
Bedard, Thomas C.,Corey, Joyce Y.
, p. 315 - 333 (2007/10/02)
The combination of Cp2TiCl2 and nBuLi provides an effective catalyst for alcoholysis of the model silanes n-HexSiH3, PhMeSiH2, Ph2SiH2 and PhMe2SiH by ethanol, isopropanol, t-butyl alcohol and phenol.Increasing the steric bulk of the substituents on either the alcohol or the silane generally requires longer reaction periods and/or increasing temperature.All SiH bonds are converted to SiOEt groups by ethanol and a single SiH bond in secondary silanes and two SiH bonds in tertiary silanes are replaced by t-butyl alcohol.Diols including pinacol, 2,4-pentanediol and 2,5-hexanediol react with PhRSiH2 (R = Me, Ph) to give 1,3-dioxa-2-silacyclopentanes, -hexanes and -heptanes, respectively.Attempts to form caged structures by condensation of primary silanes and triols was unsuccessful.Hydrolysis of PhRSiH2 is promoted by Cp2TiCl2/n-BuLi and the siloxane is produced in quantitative yield when R = Ph and a mixture of linear disiloxanes and trisiloxanes in addition to cyclopolysilanes are produced when R = Me.Other protic reagents including acids, mercaptans, amines and enolizable ketones did not react.The effects of reaction parameters such as temperature, silane to catalyst ratio, solvent, transition metal and replacements for nBuLi were also determined.