Enantio‐ and Regioconvergent Nickel‐Catalyzed C(sp3)−C(sp3) Cross‐Coupling of Allylic Electrophiles Steered by a Silyl Group

A two‐step sequence for the enantio‐ and diastereoselective synthesis of exclusively alkyl‐substituted acyclic allylic systems with a stereocenter in the allylic position is reported. The asymmetric induction and the site selectivity are controlled in an enantio‐ and regioconvergent nickel‐catalyzed C(sp3)−C(sp3) cross‐coupling of regioisomeric mixtures of racemic α‐/γ‐silylated allylic halides and primary alkylzinc reagents. The silyl group steers the allylic displacement towards the formation of the vinylsilane regioisomer, and the resulting C(sp2)−Si bond serves as a linchpin for the installation of various C(sp3) substituents in a subsequent step. A nickel‐catalyzed cross‐coupling of regioisomeric mixtures of racemic silylated allylic halides and primary alkylzinc reagents enables the enantio‐ and regioconvergent synthesis of vinylsilanes with an allylic stereocenter. The silyl group controls the regiochemical outcome and is at the same time a placeholder for another alkyl substituent that can be installed in a subsequent cross‐coupling.