Visible-light excitation of iminium ions enables the enantioselective catalytic β-alkylation of enals
作者:Mattia Silvi、Charlie Verrier、Yannick P. Rey、Luca Buzzetti、Paolo Melchiorre
DOI:10.1038/nchem.2748
日期:2017.9
organisms. Herein we demonstrate that the direct excitation of chiral iminium ions can unlock unconventional reaction pathways, enablingenantioselective catalytic photochemical β-alkylations of enals that cannot be realized via thermal activation. The chemistry uses readily available alkyl silanes, which are recalcitrant to classical conjugateadditions, and occurs under illumination by visible-light-emitting
Catalytic Selective Metal-Free Cross-Coupling of Heteroaromatic <i>N</i>-Oxides with Organosilanes
作者:Mahesh Puthanveedu、Vasiliki Polychronidou、Andrey P. Antonchick
DOI:10.1021/acs.orglett.9b01141
日期:2019.5.3
of heteroaromatic N-oxides has been developed. The method enables the synthesis of various benzylated and alkynylated N-heterocycles in a transition-metal-free manner employing organosilanes as coupling partners. The unanticipated reactivity has been exploited for the synthesis of a number of symmetrical disubstitutedacetylenes from ethynyltrimethylsilane via carbon–silicon bond metathesis.
A Practical Procedure for Iron-Catalyzed Cross-Coupling Reactions of Sterically Hindered Aryl-Grignard Reagents with Primary Alkyl Halides
作者:Chang-Liang Sun、Helga Krause、Alois Fürstner
DOI:10.1002/adsc.201301089
日期:2014.4.14
Although iron‐catalyzed cross‐coupling reactions of arylmagnesium halides with alkylhalides are well established and proceed effectively under a variety of experimental conditions, they often find limitations when working with sterically hindered aryl‐Grignardreagents. Outlined in this paper is a practical solution that allows this gap in coverage to be filled. Specifically, it is shown that bis
Reactions of a <i>N</i>-Acyliminium Ion Pool with Benzylsilanes. Implication of a Radical/Cation/Radical Cation Chain Mechanism Involving Oxidative C−Si Bond Cleavage
作者:Tomokazu Maruyama、Yusuke Mizuno、Ikuo Shimizu、Seiji Suga、Jun-ichi Yoshida
DOI:10.1021/ja068589a
日期:2007.2.1
The reaction of a N-acyliminium ion pool with benzylsilane proceeds by a chain mechanism involving oxidative C−Si bond cleavage. A radical/cation/radical cation crossover mechanism involving single electron transfer has been proposed. The effective binary system consisting of a stoichiometric amount of a benzylsilane and a catalytic amount of a more easily oxidized benzylstannane has been developed