Rapid and efficient entry to vinyl silanes from aldehydes employing a novel metalation–Peterson sequence
作者:James McNulty、Priyabrata Das
DOI:10.1039/b716897g
日期:——
Bis(trimethylsilyl)chloromethane undergoes a rapid and selective metalation with s-BuLi, yielding the nucleophilic bis(trimethylsilyl)methyl anion and providing a straightforward general entry to vinyl silanes from aromatic, aliphatic and vinyl aldehydes.
Copper-NHC-Mediated Semihydrogenation and Hydroboration of Alkynes: Enhanced Catalytic Activity Using Ring-Expanded Carbenes
作者:Jonathan W. Hall、Darcy M. L. Unson、Paul Brunel、Lee R. Collins、Mateusz K. Cybulski、Mary F. Mahon、Michael K. Whittlesey
DOI:10.1021/acs.organomet.8b00467
日期:2018.9.24
tert-butoxide complexes bearing five-, six-, and seven-membered ring N-heterocycliccarbenes, prepared by protonolysis of (NHC)CuMes with tBuOH, have been used as catalytic precursors in the semihydrogenation of alkynes with silanes/tBuOH and the hydroboration of alkynes with HBPin. Both processes proceed with high regioselectivity and show enhancements with six- and seven-membered ring carbenes.
由(NHC)CuMes与t BuOH质子分解制得的一系列带有五元,六元和七元环N-杂环卡宾的二配位叔丁醇铜配合物已被用作苯甲酸半加氢反应的催化前体。炔烃与硅烷/ t BuOH的混合,以及炔烃与HBPin的硼氢化。两种方法都具有较高的区域选择性,并显示六元和七元环卡宾具有增强作用。
Design, Synthesis, and Implementation of Sodium Silylsilanolates as Silyl Transfer Reagents
There is an increasing demand for facile delivery of silyl groups onto organic bioactive molecules. One of the common methods of silylation via a transition-metal-catalyzed coupling reaction employs hydrosilane, disilane, and silylborane as major silicon sources. However, the labile nature of the reagents or harsh reaction conditions sometimes render them inadequate for the purpose. Thus, a more versatile
The reactions of bis (trimethylsilyl) peroxide with alkyl, vinyl, alkynyl, aromatic and heteroaromatic anions are described. Depending on the reaction conditions, the trimethylsilyloxy derivatives can be obtained alone or together with the corresponding trimethylsilyl derivatives, which is sometimes the major product. Enolates, generated using magnesium diisopropylamide give the corresponding hydroxycarbonyl
Me
<sub>3</sub>
Si−SiMe
<sub>2</sub>
[
<i>o</i>
CON(
<i>i</i>
Pr)
<sub>2</sub>
−C
<sub>6</sub>
H
<sub>4</sub>
]: An Unsymmetrical Disilane Reagent for Regio‐ and Stereoselective Bis‐Silylation of Alkynes
作者:Peihong Xiao、Yanjun Cao、Yingying Gui、Lu Gao、Zhenlei Song
DOI:10.1002/anie.201800513
日期:2018.4.16
The air‐stable unsymmetrical disilane Me3Si−SiMe2[oCON(iPr)2C6H4] has been developed for bis‐silylation of alkynes. This reagent tolerates a range of functional groups, providing Z‐vinyl disilanes in high yields. It is proposed that the phenyl‐ring‐tethered amide group directs oxidative addition of Pd0 into the Si−Si bond, which might facilitate formation of a six‐membered Pd cycle, generating products
空气稳定的不对称乙硅烷Me 3 Si-SiMe 2 [ o CON(i Pr)2 C 6 H 4 ]已开发用于炔烃的双硅烷化反应。该试剂可耐受多种官能团,可提供高收率的Z乙烯基乙硅烷。有人建议苯环束缚的酰胺基团将Pd 0氧化加成到Si-Si键中,这可能有助于形成六元Pd循环,从而产生具有良好或极好的区域选择性的产物。