Dehydrative C–H Alkylation and Alkenylation of Phenols with Alcohols: Expedient Synthesis for Substituted Phenols and Benzofurans
作者:Dong-Hwan Lee、Ki-Hyeok Kwon、Chae S. Yi
DOI:10.1021/ja302710v
日期:2012.5.2
well-defined cationic Ru-H complex catalyzes the dehydrative C-H alkylation reaction of phenols with alcohols to form ortho-substituted phenol products. Benzofuran derivatives are efficiently synthesized from the dehydrative C-H alkenylation and annulation reaction of phenols with 1,2-diols. The catalytic C-H coupling method employs cheaply available phenols and alcohols, exhibits a broad substrate scope, tolerates
Lewis acidic nature of boron trichloride (BCl3) to coordinate to the carbonyl functionality was exploited for the synthesis of benzofurans via dehydrative cyclization. This mild and efficient procedure allowed for facile access to a number Of highly Substituted benzofurans in a regioselective manner. The Structural requirement for the successful cyclodehydration was examined in the cases, where competitive demethylation could occur. (C) 2008 Elsevier Ltd. All rights reserved.