Zinc‐Catalyzed Dual C–X and C–H Borylation of Aryl Halides
作者:Shubhankar Kumar Bose、Andrea Deißenberger、Antonius Eichhorn、Patrick G. Steel、Zhenyang Lin、Todd B. Marder
DOI:10.1002/anie.201505603
日期:2015.9.28
A zinc‐catalyzed combined CX and CH borylation of arylhalides using B2pin2 (pin=OCMe2CMe2O) to produce the corresponding 1,2‐diborylarenes under mild conditions was developed. Catalytic CH bond activation occurs ortho to the halide groups if such a site is available or meta to the halide if the ortho position is already substituted. This method thus represents a novel use of a group XII catalyst
Visible-Light-Induced Ni-Catalyzed Radical Borylation of Chloroarenes
作者:Ya-Ming Tian、Xiao-Ning Guo、Ivo Krummenacher、Zhu Wu、Jörn Nitsch、Holger Braunschweig、Udo Radius、Todd B. Marder
DOI:10.1021/jacs.0c08834
日期:2020.10.21
borylation reactions proceed via a radical process. EPR studies demonstrate that [Ni(IMes)2] undergoes very fast chlorineatomabstractionfrom aryl chlorides to give [NiI(IMes)2Cl] and aryl radicals. Control experiments indicate that light promotes the reaction of [NiI(IMes)2Cl] with aryl chlorides generating additional aryl radicals and [NiII(IMes)2Cl2]. The aryl radicals react with an anionic sp2-sp3
Regioselective Synthesis of <i>o</i>-Benzenediboronic Acids via Ir-Catalyzed <i>o</i>-C–H Borylation Directed by a Pyrazolylaniline-Modified Boronyl Group
Ir-catalyzed ortho-directed C–H borylation of pyrazolylaniline (PZA)-modified arylboronic acids with bis(pinacolate)diboron afforded o-benzenediboronic acids in which two boronyl groups are differentially modified by pinacol (PIN) and PZA. By using this borylation after nondirected Ir-catalyzed C–H borylation, o-benzenediboronic acids are conveniently synthesized from unfunctionalized arenes. The differentially
Arynes are found to be facilely inserted into bis(pinacolato)diboron by using a platinum–isocyanide catalyst, affording diverse 1,2-diborylarenes, which can be converted into o-terphenyls via Suzuki–Miyaura coupling reaction.