No abstract

The present review aims to provide an overview of recent developments in photochemical and photocatalyzed synthesis of α‐aryl carbonyls via formation of C(sp)2−C(sp)3 bonds. The approaches described are based on the use of light as the exclusive energy source for the generation of highly reactive carbon radicals, cations or radical ions as the key intermediates of the process. Such strategies efficiently compete with traditional routes, that require the combined use of transition metal complexes, ligands, additives and often harsh reaction conditions.

A direct transformation of non-preactivated benzyl alcohols to benzyl stannanes and benzyl silanes was realized through Pd-catalyzed C(sp 3 )−O activation process. By using versatile tin and silicon sources, these reactions exhibit a broad substrate scope and a high efficiency under mild conditions, affording functionalized benzyl and allylic stannanes and benzylsilanes with high yields. The successful implementation of gram-scale stannylation/silylation as well as the one-pot Stille coupling reaction demonstrates the potential application of this method in organic synthesis. Both experimental and theoretical investigations reveal the mechanistic details of this reaction.