Fe-catalyzed B–H and Si–H insertion reactions of gem-dihaloalkanes

Abstract

Transition metal-catalyzed B–H and Si–H insertion reactions afford efficient routes to the synthesis of valuable organoboranes and organosilicon compounds. Typically, these methods employ carbene precursors bearing resonance-stabilizing substituents. Herein, we present an approach involving Fe-catalyzed B–H and Si–H insertion reactions of gem-dichloroalkanes. In contrast to previous strategies, our method uses gem-dihaloalkanes as non-stabilized carbene precursors and operates through a radical reaction pathway. Mechanistic investigations, encompassing deuterium-labelling experiments, crossover experiments, kinetic isotope effect studies, and control experiments, provide evidence supporting the intermediacy of an iron carbene and a concerted Si–H insertion process. Notably, this protocol exhibits excellent functional group compatibility, delivering a diverse array of aliphatic boranes and organosilicon compounds under mild conditions.