Synthesis of 6‐ and 8‐Halogenosubstituted 3‐Quinoline‐Sulfonic Acid Derivatives[1]

Treatment of 3,6‐di‐ and 3,6,8‐trihalogenosubstituted quinolines 1 with sodium alkanethiolates was carried out regioselectively at C3 of the pyridine ring, affording the corresponding halogenosubstituted 3‐methylsulfanylquinolines 2 and 3‐phenylmethylsulfanylquinolines 3 . The structures of 2 and 3 were assigned by NMR studies, including ¹H‐detected one‐bond (C–H) HSQC and long‐range HMBC, in addition to NOE experiments. Benzyl derivatives 3 were oxidatively chlorinated to obtain the title quinolinesulfonyl chlorides.