Synthesis of Arylated Benzofurans by RegioselectiveSuzuki-Miyaura Cross-Coupling Reactions of 2,3-Dibromobenzofurans- and 2,3,5-Tribromobenzofurans
作者:M. Hussain、N. Thai Hung、N. Abbas、R. A. Khera、I. Malik、T. Patonay、N. Kelzhanova、Z. A. Abilov、A. Villinger、P. Langer
DOI:10.1002/jhet.2083
日期:2015.3
Arylatedbenzofurans were prepared by regioselective Suzuki–Miyaura cross‐coupling reactions of 2,3‐dibromobenzofuran. The reactions proceeded with very good site‐selectivity in favor of the more electron deficient position 2. The Suzuki–Miyaura reactions of 2,3,5‐tribromobenzofuran also proceeded in favor of position 2.
The Suzuki-Miyaura reaction of 2,3-dibromobenzofuran with two equivalents of boronic acids gave 2,3-diarylbenzofurans. The reaction with one equivalent of arylboronic acids resulted in site-selective formation of 2-aryl-3-bromobenzofurans. 2,3-Diarylbenzofurans containing two different aryl groups were prepared from 2,3-dibromobenzofuran in a one-pot protocol by sequential addition of two different boronic acids. (C) 2010 Elsevier Ltd. All rights reserved.