Oxidative radical divergent Si-incorporation: facile access to Si-containing heterocycles

A copper-catalyzed oxidative radical strategy to avoid the use of the highly expensive noble metal/ligand catalytic systems is described, which allows selective activation of dual chemical bonds around the Si-atom center relying on the nature of alkylsilanes. While for tertiary silanes selective functionalization of Si-H/silyl C(sp³)-H bonds in intermolecular oxidative annulation cascades with N-(2-(ethynyl)aryl)acrylamides toward silino[3,4-c]quinolin-5(3H)-ones, when using secondary silanes and HSi(TMS)₃, dual Si-H bonds or Si-H/Si-Si bonds are selectively cleaved leading to 4H-silolo[3,4-c]quinolin-4-ones.