Switchable Reactivities of Metalated Phosphasilenes Regulated by Reversible 1,2‐Metal Migration

Abstract

Abstract Anionic reagents with silicon‐containing double bonds, M(R)Si═ER n (E = main group elements), have garnered significant interest owing to their unique metal‐mediated reactivity and their potential in transferring the Si═E unit. Within this domain, the intriguing field of Si ‐metalated phosphasilenes remains uncharted. Herein, we present a novel strategy for the efficient synthesis of P ‐metalated phosphasilenes and their subsequent transformation into Si ‐metalated phosphasilenes via a distinctive phosphinosilylene intermediate formed during a metal‐mediated skeletal rearrangement. While P ‐metalated phosphasilenes exhibit a pronounced π‐bonding character in the Si═P linkage, the skeletal rearrangement attenuates both the Si═P and Si─M bonds in the resulting Si ‐metalated phosphasilenes, rendering them effective silylene equivalents. Moreover, formal transmetallation of Si ‐metalated phosphasilene with dimetal carbonyl complexes provides access to a broader array of Si ‐metalated analogues. This transmetallation proceeds through the phosphinosilylene intermediate, as evidenced by the isolation of a silylene–dimanganese complex, thereby revealing an uncharted mechanistic manifold for this class of transformations.