Br-radical-mediated [3+2] annulation: synthesis of 2-bromomethyl-substituted alkenylcyclopentanes by the reaction of alkenylcyclopropanes with allyl bromides under photo irradiation

• 来源期刊: 中国科学:化学（英文版）
• 年，卷（期）: 2019,（11）
• 页码范围: 1525-1528
• 页数: 4页
• 语种: 英文

摘要

A radical chain addition of allyl bromides 2 to alkenylcyclopropanes 1 resulted in [3+2] annulation to give 2-bromomethyi-alkenylcyclopentanes 3 in good yields (16 examples).In this reaction,two kinetically fast radical reactions,cyclopropylcarbinyl radical-ring-opening and 5-exo-radical eyclization,preceded the β-fragmentation of a bromine radical to make the formal cycloaddition possible.