electron-withdrawing group on the α-carbon using tris(triphenylphosphine)chlororhodium as a catalyst is described. Solvolysis of these silyl ethers and silyl enol ethers afforded the corresponding reduced products. The hydrosilylation of α,β-unsaturated carbonyl compounds was found to proceed by 1,4-addition. An oxidative adduct of triethylsilane to the rhodium-(I) complex was obtained as a reaction intermediate
Nickel-Catalyzed Decarboxylative Coupling of Redox-Active Esters with Aliphatic Aldehydes
作者:Jichao Xiao、Zhenning Li、John Montgomery
DOI:10.1021/jacs.1c11170
日期:2021.12.22
The addition of alkyl fragments to aliphaticaldehydes is a highly desirable transformation for fragment couplings, yet existing methods come with operational challenges related to the basicity and instability of the nucleophilic reagents commonly employed. We report herein that nickel catalysis using a readilyavailable bioxazoline (BiOx) ligand can catalyze the reductive coupling of redox-active
The action of triethylsilane on α-ethylenic aldehydes has been studied in the presence of two types of nickel catalysts as well as palladium on charcoal. Two phenomena can result: either 1,2 or 1,4 additions only, the trans-1,4 adduct being predominant, or a competition between these two additions and coupling reactions. A comparative regioselective and stereoselective study was carried out making
Action de trialkylsilanes sur les aldehydes aliphatiques
作者:Emile Frainnet、Rolland Bourhis
DOI:10.1016/s0022-328x(00)94004-x
日期:1975.7
The possibility of obtaining enoxysilanes by action of trialkylsilanes HSiR′3 on aliphatic aldehydes RCHO in the presence of various nickel catalysts has been closely studied. Mechanisms are proposed to interpret the results.
Nickel-catalyzed reductive coupling of unactivated alkyl bromides and aliphatic aldehydes
作者:Cole L. Cruz、John Montgomery
DOI:10.1039/d1sc03712a
日期:——
A mild, convenient coupling of aliphaticaldehydes and unactivated alkyl bromides has been developed. The catalytic system features the use of a common Ni(II) precatalyst and a readily available bioxazoline ligand and affords silyl-protected secondary alcohols. The reaction is operationally simple, utilizing Mn as a stoichiometric reductant, and tolerates a wide range of functional groups. The use
已开发出一种温和、方便的脂肪醛和未活化烷基溴的偶联方法。该催化系统使用常见的 Ni( II ) 预催化剂和易于获得的生物恶唑啉配体,并提供甲硅烷基保护的仲醇。该反应操作简单,使用 Mn 作为化学计量还原剂,并且可以耐受多种官能团。使用 1,5-己二烯作为添加剂是一个重要的反应参数,可显着提高产量。最初的机械实验支持一种以 α-甲硅烷氧基镍物种为特征的机制,该物种通过还原性交叉偶联途径对烷基溴进行正式氧化加成。