Visible-light-induced radical reaction of acylsilanes through solvent-controlled Norrish type I cleavage

The development of innovative photoinduced reactions for acylsilanes remains a significant challenge in organic synthesis, primarily due to their inherent propensity to undergo 1,2-Brook rearrangement upon photoirradiation, generating siloxycarbene intermediates. In this study, we demonstrate that the reactivity of acylsilanes under visible light can be regulated to effectively suppress the undesirable 1,2-Brook rearrangement. This control is achieved by employing polar solvents as the reaction medium during photoirradiation, strategically redirecting the reaction pathway toward Norrish type I cleavage. As a result, acylsilanes afford acyl radicals and silyl radicals, which enables the selective capture of acyl radicals by diselenides for the chemoselective synthesis of a diverse array of selenoester products.