Ligand-Controlled Regiodivergent Carbosilylation of 1,3-Dienes via Nickel-Catalyzed Three-Component Coupling...

The regiodivergent carbosilylation of 1,3-dienes presents a formidable challenge due to inherently complex selectivity control over multiple potential reaction pathways. Here, we report a ligand-controlled, regiodivergent carbosilylation of 1,3-dienes with aldehydes and silylboranes, achieving unprecedented site-selectivity using nickel catalysts with distinct phosphine ligands. The use of triethylphosphine promotes 4,3-addition selectivity, while employing (2-biphenyl)dicyclohexylphosphine facilitates 4,1-addition selectivity. This method displays excellent regio- and diastereoselectivity, as well as a broad substrate scope and substantial functional group tolerance. Mechanistic studies indicate that the ligand choice is crucial for directing the reaction pathway and stabilizing π-allyl-nickel intermediates. Our protocol provides a practical and efficient approach to synthesizing valuable functionalized allylsilanes, which are important in various synthetic applications.