Frustrated Lewis Pair-Promoted Organocatalytic Transformation of Hydrosilanes into Silanols with Water Oxidant

Abstract

Owing to their unique properties, the silanols have attracted intense attention but remain challenging to prepare from the organocatalytic oxidation of hydrosilanes using H₂O as a green oxidant. Herein, we employ a frustrated Lewis pair (FLP) to successfully suppress the formation of undesired siloxanes and produce silanols in high to excellent yields in the presence of H₂O. Mechanistic studies suggest that the reaction is initiated with the activation of FLP by H₂O rather than by silanes and goes through a concerted S_N2 mechanism. More importantly, the combination of the FLP-catalyzed oxidation of hydrosilanes with B(C₆F₅)₃-catalyzed dehydrogenation enables us to realize the precise synthesis of sequence-controlled oligosiloxanes. This method exhibits a broad substrate scope and can be easily scaled up, thus exhibiting promising application potentials in the precision synthesis of silicon-containing polymer materials.