Rhodium-Catalyzed Intermolecular Silylation of C -H by Silacyclobutanes.

The signature reactivity of silacyclobutane (SCB) is their cycloaddition reactions with various π bonds. Recently, the first cases were disclosed where SCBs reacted with both C -H and C -H σ bonds in an intramolecular fashion. Herein, it is reported that SCB is also an efficient reagent for C -H bond silylation. Thus, rhodium-catalyzed intermolecular reactions between SCBs and terminal alkynes produced a series of symmetrical and unsymmetrical tetraorganosilicons bearing a C -Si functionality. Preliminary studies suggested that the reaction did not involve a cycloaddition pathway, but instead a direct activation of C -H bonds.