Highly Selective Dehydrogenative Silylation of Alkenes Catalyzed by Rhenium Complexes
作者:Yanfeng Jiang、Olivier Blacque、Thomas Fox、Christian M. Frech、Heinz Berke
DOI:10.1002/chem.200802019
日期:2009.2.16
chemicals: Rhenium(I) complexes of type [ReBr2(L)(NO)(PR3)2] (L=H2 (1), CH3CN (2), ethylene (3); R=iPr (a), cyclohexyl (b)) proved to be suitable catalyst precursors for the highlyselectivedehydrogenativesilylation of alkenes. Two types of rhenium(I) hydride species, [ReBrH(NO)(PR3)2] (4) and [ReBr(η2‐CH2CHR1)H(NO)(PR3)2] (5), were found in the [ReBr2(L)(NO)(PR3)2]‐catalyzeddehydrogenative silylation
选择化学药品:[ReBr 2(L)(NO)(PR 3)2 ]类型的R(I)配合物(L = H 2(1),CH 3 CN(2),乙烯(3); R = i Pr (a),环己基(b))被证明是用于烯烃的高度选择性脱氢甲硅烷基化的合适催化剂前体。两种类型的铼(I)氢化物种,[ReBrH(NO)(PR 3)2 ](4)和[ReBr(η 2 -CH 2 CHR 1)H(NO)(PR 3)2 ](5),是在[ReBr 2(L)(NO)(PR 3)2 ]催化的烯烃脱氢甲硅烷基化反应中发现的。
Nickel(<scp>ii</scp>)-catalyzed reductive silylation of alkenyl methyl ethers for the synthesis of alkyl silanes
A new one pot protocol has been developed for the reductive silylation of alkenyl methyl ethers using Et3Si–BPin and HSiEt3 with nickel(II) catalyst. Styrene type methyl ethers, multi-substituted vinyl methyl ethers, heterocycles and unconjugated vinyl ethers are all tolerated to form alkyl silanes. Mechanistic study reveals that it is a cascade of a C–O bond silylation and vinyl double bond hydrogenation
Rh-catalyzed anti-Markovnikov hydrosilylation of terminal alkenes and tertiary silanes using readily-available PPh3 as the ligand was reported. This method facilitated the effective synthesis of alkylsilanes with a wide substrate scope and high yields. Remarkably, both an unprecedented catalytic efficiency (TON up to 10,000) and excellent selectivity for the reaction of styrene and diethoxymethylsilane