Regioselective functionalization of 2-(2′-fluorophenyl)-3-cyanopyridine and its cyclization to benzo[h]-1,6-naphthyridines

Benzo[h]-1,6-naphthyridines and 5-ones, selectively functionalized at C-2, C-3, C-5 and C-10, were obtained by alkyllithium-, lithium amide- or potassium hydroxide-induced anionic cyclization of 3-cyano-2-(2-fluorophenyl)pyridine, which was functionalized regioselectively at positions 4, 5, 6, and 6′.