Oxidation of 1-benzyldihydroisoquinolines or 1-benzyltetrahydroisoquinolines with dioxygen to 1-benzoylisoquinolines

An environmental-benign methodology to synthesize 1-benzoylisoquinolines from 1-benzyl-3, 4-dihydroisoquinolines or 1-benzyl-1,2,3,4-tetrahydroisoquinolines using dioxygen as an oxidant was developed. This methodology in combination with Bischler-Napieralski reaction leads to a facile synthesis of 1-benzoylisoquinolines from phenylacetic acids and phenylethanamines.