Synthesis of 2‐Benzyl‐3,4‐dihydronaphthalenes via Oxidative Radical Opening/Cyclization of Methylenecyclopropanes with Potassium Benzyltrifluoroborates

Abstract

A Copper-catalyzed benzylation of methylenecyclopropanes with potassium benzyltrifluoroborate salts has been developed to produce 2-benzyl-3,4-dihydronaphthalenes in moderate to good yields. This oxidative cyclization reaction proceeds well via a sequence of radical addition, ring-opening, and cyclization. This protocol represents a new example of methylenecyclopropane oxidative cyclization and tolerates a diverse range of substrate.