Insertion of Cyclic Alkyl(amino) Carbene into the Si–H Bonds of Hydrochlorosilanes

Carbenes are known for their ability to abstract HCl from hydrochlorosilanes to form carbene hydrochloride adducts. In contrast, the Si–H bond insertion products RSiCl2(cAACH) (2, 4, 6, and 8) have been formed in the reaction of RSiHCl2 [R = Ar­(SiMe3)N (1), Cp* (3), PhC­(NtBu)2 (5), Cl (7); Ar = 2,6-iPr2C6H3] with a cyclic alkyl­(amino) carbene (cAAC:) irrespective of the steric demand of the R group. The new products have been characterized by various analytical tools including X-ray crystallography, electron ionization mass spectrometry, and NMR spectroscopy. Theoretical investigations have also been performed to understand why cAAC prefers insertion into the Si–H bond rather than the dehydrohalogenation pathway.