Photocatalytic asymmetric cross-couplings via a radical Brook rearrangement

Abstract

Photocatalytic asymmetric cross-coupling of aryl bromides with organosilicon reagents bearing an α-hydroxyalkyl group has been achieved via a dual catalysis strategy. The use of a benzophenone derivative that allows PCET with the silane coupling partner under photoexcitation is crucial for the generation of an α-silyloxyalkyl radical via a Brook rearrangement for subsequent nickel-mediated C–C bond formation. This metallaphotoredox system offers an efficient approach for synthesizing enantioenriched benzylic alcohols with compatibility across a range of functional groups.