Nickel‐Catalyzed Enantioselective Reductive Heck Reaction of Olefins with Aryl Bromides and Chlorides Enabled by Chiral NHC Ligands

Despite significant advances in catalytic asymmetric reductive Heck reaction, most reported methods rely on highly reactive aryl electrophiles and exhibit a limited olefin scope. Expanding this transformation to employ more abundant and cost-effective aryl bromides and chlorides with common olefins has remained a major challenge, owing to the inertness of C─Br and C─Cl bonds and the resulting difficulty in achieving chemo-, regio-, and stereocontrol. Here, we report that nickel catalysts combined with chiral dihydroimidazolium-derived N-heterocyclic carbene ligands bearing remote meta-substitution enable highly efficient and enantioselective reductive Heck reaction of a broad range of olefins-including styrenes, 1,3-dienes, and aliphatic alkenes-with aryl bromides and chlorides. Experimental studies and DFT calculations elucidated the origins of stereo induction and structure-reactivity relationships. This robust methodology provides streamlined access to structurally diverse, enantioenriched benzylic frameworks.