Amidrazones. <b>6</b>. Synthesis of 1,2,4‐thiadiazoles by thermolysis of <i>N</i>³‐thiocarbamoylamidrazone ylides

Abstract

Abstract Reaction of N 3 ‐unsubstituted amidrazone ylides ( 1a and 1b ) with alkyl or aryl isothiocyanates gives N 3 ‐thiocarbamoylamidrazone ylides ( 2 ). Thermolysis of 2 gives 3‐alkyl(or aryl)‐5‐alkyl(or aryl)amino‐1,2,4‐thiadiazoles ( 3a‐i ).