Functionalization of tetraorganosilanes and permethyloligosilanes at a methyl group on silicon via iridium-catalyzed C(sp³)-H borylation

In the presence of an iridium 3,4,7,8-tetramethyl-1,10-phenanthroline catalyst, a methyl group on the silicon atom of alkyltrimethylsilanes undergoes selective C-H borylation with bis(pinacolato)diboron in cyclooctane at 135 C to give alkyl(borylmethyl)dimethylsilanes. The C-H borylation of tetramethylsilane takes place efficiently at 100 C. Permethyloligosilanes can also undergo C-H borylation without cleavage of the Si-Si bonds.