B(C6F5)3-Catalyzed Synthesis of (Catecholato) silanes and Their Application in Ring-Expansion Reactions

(Catecholato)silanes, which exhibit reversible monomer–dimer interconversion through Si–O/Si–O σ-bond metathesis, lack efficient synthetic routes. In this study, a B(C 6 F 5 ) 3 -catalyzed approach was developed to prepare (catecholato)silanes via dehydrogenative and dehydrocarbonative condensation of catechols and their derivatives with dihydrosilanes, thereby avoiding the use of corrosive chlorosilanes and the formation of salt byproducts. Furthermore, selective ring-expansion reactions between (catecholato)silanes and cyclotrisiloxanes were achieved under imidazole catalysis, affording novel 11-membered cyclic compounds. Overall, these findings advance the synthetic methodology for (catecholato)silanes and facilitate the construction of siloxane-based cyclic architectures.