Electrochemical annulation of 1,2,3-benzotriazinones with alkynes to access isoquinolin-1(2H)-ones.

An eco-friendly approach for electrochemical radical cascade annulation of 1,2,3-benzotriazinones with alkynes is described. Under catalyst-free and external reductant-free electrolysis conditions, a range of isoquinolin-1(2H)-ones were obtained in moderate to good yields. Cyclic voltammetry and control studies suggest that the reaction proceeds via a radical pathway. Furthermore, this approach could be easily scaled up.