Ligand‐Controlled Regiodivergent Carbosilylation of 1,3‐Dienes via Nickel‐Catalyzed Three‐Component Coupling Reactions

Abstract 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.