Reinvestigation of Rearrangement of Benzodiazepinediones into Quinoleines Under Microwave or Conventional Heating Conditions

Microwave or conventional heating of pyrrolo and pyrido[2,1-c][1,4]benzodiazepines in boiling phosphorus oxychloride led to rearranged products like benzo[h][1,6]naphthyridine and azepino[3,2-c]quinoleine and not to cyclopenta[b][1,4]benzodiazepine and tetrahydrodibenzo[b,f][1,4]diazepine as initially described.