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(sp 3 )-H bonds in intermolecular oxidative annulation cascades with N -(2-(ethynyl)aryl)acrylamides toward silino[3,4- c ]quinolin-5(3 H )-ones, when using secondary silanes and HSi(TMS) 3 , dual Si-H bonds or Si-H/Si-Si bonds are selectively cleaved leading to 4 H -silolo[3,4- c ]quinolin-4-ones. Oxidative radical cleavage of Si-H/silyl C(sp 3 )-H bonds, dual Si-H bonds and Si-H/Si-Si bonds toward Si-heterocycles is presented.