Synthesis of 4-Amino-3-quinolinesulfonic Acids and 4-Aminoquinolines

The hydrolysis of 4-chloro-3-quinolinesulfonyl chloride (1) gives 4-chloro-3-quinolinesulfonic acid (2) or 1,4-dihydro-4-0x0-3-quinolinesulfonic acid (3).Compound (2) reacts with primary and secondary aliphatic or primary aromatic mines to give 4-amin-3-quinolinesulfonic acids (4).Desulfonation of quinolinesulfonic acids (2,3,4) yields 4(lH)-quinolinone or 4-aminoquinolines (5).