Intermolecular Carbosilylation of α‐Olefins with C(sp3)−C(sp) Bond Formation Involving Silylium‐Ion Regeneration

摘要

Abstract A regioselective addition of alkynylsilanes across unactivated, terminal alkenes is reported. The reaction is initiated by the capture of a sterically unhindered silylium ion by a silylated phenylacetylene derivative to form a bis(silylated) ketene‐like carbocation. This in situ‐generated key intermediate is the actual catalyst that maintains the catalytic cycle by a series of electrophilic addition reactions of silylium ions and β‐silicon‐stabilized carbocations. The computed reaction mechanism is fully consistent with the experimental findings. This unprecedented two‐component carbosilylation establishes a C(sp3)−C(sp) bond and a C(sp3)−Si bond in atom‐economic fashion.