A new synthesis of symmetrical 2,5‐diaryl‐1,3,4‐thiadiazoles

Abstract Treatment of aromatic aldehydes with sulfur and hydrazine hydrate in the ratio 1:2:3, respectively, under the Willgerodt conditions affords the title compounds in excellent yields and in a good state of purity. Under the same conditions 2‐chloro and 2,6‐dichlorobenzaldehyde yield 3 H ‐1,2‐benzodithiole‐3‐thione and bis‐(2,6‐dichlorobenzyl)tetrasulfide, respectively.