Synthesis of 3‐thiocyanato‐1<i>H</i>,3<i>H</i>‐quinoline‐2,4‐diones

Abstract

Abstract 4‐Hydroxy‐1 H ‐quinolin‐2‐ones ( 1 ) react with thiocyanogen in acetic acid to the corresponding 3‐thiocyanato‐1 H ,3 H ‐quinoline‐2,4‐diones ( 2 ) in good yields. In some cases, 3‐bromo‐1 H ,3 H ‐quinoline‐2,4‐diones ( 4 ) were isolated as minor reaction products. Compounds 2 are very reactive towards nucleophiles and easily hydrolyze to the corresponding 4‐hydroxy‐1 H ‐quinoline‐2‐ones ( 1 ).