Hemilabile P,N-ligand-assisted gold catalyzed Hiyama allylation to access allylarenes and 1,4-diene derivatives

Oxidant-free gold-catalyzed reactions are emerging as a novel synthetic tool for organic transformations. Herein, we report a hemilabile P,N-ligand-assisted gold-catalyzed Hiyama cross coupling reaction of aryl and alkenyl iodides with allylsilanes. The reaction proceeds smoothly without an external oxidant under mild conditions, providing access to a series of allylarenes and 1,4-diene derivatives in good to excellent yields. This transformation features a broad substrate scope, good functional group tolerance, and compatibility with heteroaromatic substrates. The (P,N) ligand MeDalphos-facilitated gold-catalyzed process presents a new approach for the synthesis of allylarenes and 1,4-diene derivatives. Moreover, mechanistic investigations including NMR and mass spectrometric studies strongly support the proposed mechanism of the reaction.