Facile Synthesis of 3-Substituted and 1,3-Disubstituted Quinolin-2(1H)-ones from 2-Nitrobenzaldehydes

2-Nitrobenzaldehydes were reduced with iron powder to 2-aminobenzaldehydes, which were reacted immediately with acyl chlorides to provide 2-carboxamidobenzaldehydes (1) with overall yields of 71-90 %.Reaction of 1 with base provided 3-substituted quinolin-2(1H)-ones with 63-97 % yields.Treatment of 1 with methyl iodide and base gave 1-methyl-3-substituted quinolin-2(1H)-ones with 82-95 % yields, whereas the treatment with isopropyl iodide gave 1-isopropyl-3-substituted quinolin-2(1H)-ones with 7-42 % yields.