Anchimeric assistance by γ-substituents Z, Z=MeO, PhO, MeS or PhS, in reactions of the bromides (Me3Si)2(ZMe2Si)CSiMe2Br with AgBF4
作者:Colin Eaborn、Anna Kowalewska、J David Smith、Wlodziemierz A Stańczyk
DOI:10.1016/s0022-328x(01)01169-x
日期:2001.12
products by 19F-NMR spectroscopy, have led to the following approximate relative reactivities of the bromides and so to the relative abilities of the γ-Z groups to provide anchimericassistance to the leaving of Br− in this reaction: Me, 1; Ph, 40; PhO, 3400; PhS, 5000; MeS, 7000; MeO, 54 000. In methanolysis in CH2Cl2, (Me3Si)2(MeOMe2Si)CSiMe2Cl has been found to be roughly 120 times as reactive as
Reactions at highly sterically hindered organosilicon centres. Chemistry of (Me3Si)3 CSiPhHI, (Me3Si)3CSiPh(OMe)I, and related species
作者:Zakariah H. Aiube、Colin Eaborn
DOI:10.1016/0022-328x(91)86400-k
日期:1991.12
(Me3Si)2C(SiPhHMe)(SiMe2F). The reactions of the iodide TsiSiPh(OMe)I with AgY give the unrearranged products TsiSiPh(OMe)Y, except that reaction with AgO2CMe in MeCO2H seems also to give some (Me3Si)2C[SiPh(OMe)Me](SiMe2O2CMe). Treatment of the hydrides TsiSiPhHX (X = OMe, OH, or F) with one molar proportion of ICl in CCl4 gives the iodides TsiSiPhXI, and these react with a further molar proportion of
Reactions of some sterically-hindered organosilicon hydrides and iodides with halogens
作者:Colin Eaborn、Abdulrahman I. Mansour
DOI:10.1016/0022-328x(83)80129-6
日期:1983.10
The reaction of TsiSiMe2H (I) (Tsi = (Me3Si)3C) with I2 or with a molar equivalent of ICl gives the iodide TsiSiMe2I (II) in hydroxylic media (MeOH, CH3CO2H, CF3CO2H) as it does in CCl4. The reaction with I2 is very fast in CF3CO2H, but in MeOH is only about as fast as in CCl4. The iodide II reacts with ICl in MeOH to give a mixture of TsiSiMe2OMe (III) and TsiSiMe2Cl (IV), but the reaction is markedly
Reaction of the (Dichloromethyl)oligosilanes R(Me3Si)2Si−CHCl2 (R = Me, Ph, Me3Si) with Organolithium Reagents and the Synthesis of Novel Kinetically Stabilized Silenes
silanols, by the addition of methanol to give methoxysilanes and by formal [2+2] cycloadditions with benzaldehyde to afford stable 1,2-oxasiletanes. 1-Methyl-1-(2,4,6-triisopropylphenyl)-2,2-bis(trimethylsilyl)silene (8a), produced as intermediate from 1a and 2,4,6-triisopropylphenyllithium (1:2), proved to be unstable in the presence of excess aryllithium compound. Thus, only the addition product Me(2