A Selective Synthesis of (E)-Vinylsilanes by Cationic Rhodium Complex-Catalyzed Hydrosilylation of 1-Alkynes and Tandem Hydrosilylation/Isomerization Reaction of Propargylic Alcohols to .beta.-Silyl Ketones
摘要:
(E)-丙二烯二硅烷通过使用[Rh(COD)(2)]BF4/2PPh(3)协同催化的水硅化反应获得了高选择性,适用于多种一元炔烃底物。丙炔醇的水硅化反应产生γ-硅基 allylic 醇2h-R,并提供了一种高效产率的构象选择性高的旋多糖醇。该反应无需保护醇的功能性即可进行。由此产生的(E)-γ-硅基 allylic 醇可以通过转化得到β-硅基酮。此外,该[Rh(COD)(2)]BF4/2PPh(3)催化还可以催化丙炔醇的同分异构化反应。Furthermore, a one-pot tandem hydrosilylation-isomerization of secondary propargylic alcohols can be achieved using this approach.
Silicon-Directed Rhenium-Catalyzed Allylic Carbaminations and Oxidative Fragmentations of γ-Silyl Allylic Alcohols
作者:Sanjay W. Chavhan、Matthew J. Cook
DOI:10.1002/chem.201400104
日期:2014.4.22
A highly regioselective allylic substitution of β‐silyl allylic alcohols has been achieved that provides the branched isomer as a single product. This high level of regiocontrol is achieved through the use of a vinyl silane group that can perform a Hiyama coupling providing 1,3‐disubstituted allylic amines. An unusual oxidative fragmentation product was also observed at elevated temperature that appears
Markovnikov Hydrosilylation of Alkynes with Tertiary Silanes Catalyzed by Dinuclear Cobalt Carbonyl Complexes with NHC Ligation
作者:Dongyang Wang、Yuhang Lai、Peng Wang、Xuebing Leng、Jie Xiao、Liang Deng
DOI:10.1021/jacs.1c06583
日期:2021.8.18
with PhC≡CH and HSiEt3 can furnish the dinuclear cobalt alkyne and mononuclear cobalt silyl complexes [(IPr)(CO)2Co(μ–η2:η2-HCCPh)Co(CO)3], [(IPr)(CO)2Co(μ-η2:η2-HCCPh)Co(CO)2(IPr)], and [(IPr)Co(CO)3(SiEt3)], respectively. Both dicobalt bridging alkyne complexes can react with HSiEt3 to yield α-triethylsilyl styrene and effect the catalytic Markovnikov hydrosilylation reaction. However, the mono(NHC)
3-pentafluorobenzyl-imidazol-2-ylidene (2) and 1,3-Bis(pentaflurobenzyl)-imidazol-2-ylidene (3)], and their respective NHC ligands as imidazolium salts are reported. The catalytic activity in hydrosilylation of two propargylicalcohols gives mainly isomers E and gem; however when cationic form of the catalysts with triphenylphosphine as an additional ligand are used, only the E isomer is observed for all the complexes
Investigation of the factors controlling the regioselectivity of the hydrosilylation of alkynes catalysed by trans-di-μ-hydridobis(tricylcohexylphosphine)bis(silyl)diplatinum complexes
作者:Constantinos A. Tsipis
DOI:10.1016/s0022-328x(00)93435-1
日期:1980.3
The hydrosilylation of terminal and internalalkynes and also of some hydroxy-alkynes catalysed by trans-di-μ-hydridobis(tricyclohexylphosphine)bis(silyl)diplatinum complexes is described. These diplatinum complexes are very efficient catalysts for such hydrosilylations; high yields (80–98%) can be obtained under mild conditions with a catalysts/reactant ratio of 10−4–10−5/1. Addition of hydrosilanes