Copper-Mediated Oxidative Functionalization of C(sp3)-H Bonds with Isoquinolines: Two-Step Synthesis of 5-Oxaprotoberberinones.

A copper-mediated oxidative functionalization of C(sp3)-H bonds with isoquinolines via a radical process without ligands was achieved. The present system exhibits a novel pathway for the preparation of N-alkyl (benzyl) isoquinolin-1(2H)-ones in moderate to high yields. In addition, this procedure provides a simple method to afford 5-oxaprotoberberinones and their derivatives in two steps.