Dimerization of Benzyl and Allyl Halides via Photoredox-Mediated Disproportionation of Organozinc Reagents

Published as part of the Special Topic Modern Radical Methods and their Strategic Applications in Synthesis

Abstract

Benzyl and allyl halides undergo homocoupling when treated with zinc in the presence of a catalytic amount of a cationic iridium(III) complex under irradiation with 400 nm light-emitting diodes. The reaction proceeds through the intermediate formation of an organozinc reagent, which disproportionates to a free radical and elemental zinc under photoredox conditions.

Key words

organozinc reagents - homocoupling - photoredox - free radicals - organic halides

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