Oaidation of 3-nitro-4-picoline with selenium dioxide gave 3-nitro-4-ppridinecarboxaldehyde . Condensation of the alde-hyde with p-toluidine gave X-(3-nitro-4-picolylidene)-p-toluidine (111), which was reduced to N-(3-amino-4-picoly1idene)-p-toluidine (IV). Condensation of the latter with acetophenone and with cyclohexanone gave 2-phenyl-1, 7-naphthyridine: md 2, 10-diaza-5, 6, 7, 8-tetrahydroanthracene(VI), respectively. Reaction of 3- ...
