Cobalt-Catalyzed Arylative Cyclization of Acetylenic Esters and Ketones with Arylzinc Reagents through 1,4-Cobalt Migration
作者:Jianming Yan、Naohiko Yoshikai
DOI:10.1021/acscatal.6b01039
日期:2016.6.3
reported a cobalt-catalyzed migratory arylzincation reaction of an alkyne that features alkenyl-to-aryl 1,4-cobalt migration and cobalt-to-zinc transmetalation as key steps. We report herein that the cobalt/arylzinc combination can also promote a cascade arylative cyclization reaction of alkynesbearing pendant ester or ketone moieties to afford benzo-fused cyclic ketone or alcohol products, respectively
Alkynones react with arylboronic acids in the presence of a rhodium(I) catalyst to afford four- and five-membered-ring cyclic alcohols equipped with a tetrasubstituted exocyclic olefin. The cyclic allylic alcohol skeleton is constructed by the carbon-carbon bond formation between the carbonyl group and an alkenylrhodium(I) intermediate formed by the regioselective addition of an arylrhodium(I) species across the carbon-carbon triple bond. (c) 2007 Elsevier Ltd. All rights reserved.