Mild, visible light-mediated decarboxylation of aryl carboxylic acids to access aryl radicals
作者:L. Candish、M. Freitag、T. Gensch、F. Glorius
DOI:10.1039/c6sc05533h
日期:——
Herein we present the first example of aryl radical formation via the visible light-mediated decarboxylation of aryl carboxylic acids using photoredox catalysis.
Rhodium-Catalyzed Intramolecular C−H Silylation by Silacyclobutanes
作者:Qing-Wei Zhang、Kun An、Li-Chuan Liu、Shuangxi Guo、Chenran Jiang、Huifang Guo、Wei He
DOI:10.1002/anie.201602376
日期:2016.5.17
Silacyclobutane was discovered to be an efficient C−H bond silylation reagent. Under the catalysis of RhI/TMS‐segphos, silacyclobutane undergoes sequential C−Si/C−H bond activations, affording a series of π‐conjugated siloles in high yields and regioselectivities. The catalytic cycle was proposed to involve a rarely documented endocyclic β‐hydride elimination of five‐membered metallacycles, which after
发现硅环丁烷是一种有效的CH键甲硅烷基化试剂。在Rh I / TMS-segphos的催化下,硅环丁烷经历了连续的C-Si / C-H键活化,从而以高收率和区域选择性提供了一系列π-共轭硅化物。有人提出催化循环涉及很少有文献记载的五元金属环的环内β-氢化物消除,在还原性消除后会产生能够进行CH活化的Si-Rh I物种。
Ag‐Catalyzed Cyclization of Arylboronic Acids with Elemental Selenium for the Synthesis of Selenaheterocycles
A general method for the synthesis of five‐membered and six‐membered selenaheterocycles through Ag‐catalyzed C−Se bond‐forming reaction is reported. This reaction proceeds via intramolecular cyclization of arylboronic acids with selenium powder. Preliminary mechanism studies demonstrate that this transformation involves a selenium‐centred radical intermediate.