Light-Driven Palladium-Radical Hybrid Species: Mechanistic Aspects and Recent Examples

Abstract Visible-light-induced palladium-mediated reactions have become a novel and promising field in organic synthesis. This photocatalytic arsenal presents complementary features towards traditional Pd chemistry, allowing the achievement of new and unique reactivities by the generation of versatile Pd-radical hybrid species. These putative intermediates can be produced by direct excitation of Pd complexes, together with organic radical precursors. This review aims at describing recent advances regarding the combination of Pd-based photocatalytic manifolds and radical generation in the functionalization of important motifs in synthetic chemistry, encompassing detailed mechanistic descriptions and relevant examples. 1 Introduction 2 Homolytic Cleavage of C–X Bonds 3 Cyclizations, Desaturations and Atom Transfer Reactions 4 Homolytic Cleavage of N–O Bonds 5 Generation through Diazo Compounds 6 Generation of Acyl Radicals 7 Generation of Ketyl Radicals 8 Conclusions