Selective functionalization of a bis-silylene

Abstract

Functionalization of N-heterocyclic carbenes (NHCs) has an important influence on their stability, Lewis donor, and acceptor properties. In this study, we report on the selective functionalization of a four-membered N-heterocyclic bis-silylene (2,6-Ar₂C₆H₃NSi:)₂ (1) (Ar = 2,4,6-iPr₃C₆H₂) with mono-oxygen sources N₂O and Me₃NO. Treatment of 1 with N₂O results in the selective formation of mono-silylene (2,6-Ar₂C₆H₃NSi(OH)₂)(2,6-Ar₂C₆H₃NSi:) (2) as a major product, along with a small amount of further oxidized product (2,6-Ar₂C₆H₃NSi(OH)₂)₂ (3). Compound 2 is the first four-membered mono-silylene with a di-coordinate silicon atom.