Acetylenic ketones. Part V. Reaction of acetylenic ketones with thiourea and some of its derivatives

Abstract

Abstract Aroylphenylacetylenes (I) reacted with thiourea and S ‐benzylisothiourea to give 4,6‐diaryl‐pyrimidine‐2(1 H )thiones (IV) and α‐aroyl‐β‐benzylmercaptostyrenes (X), respectively. Methyla‐tion and acetylation of the thiones (IV) gave the corresponding S ‐methyl‐ (V) and S‐acetyl‐ (VI) derivatives, respectively. The oxidation of these thiones gave the corresponding disulfide derivatives (VII). Reaction of α‐aroyl‐β‐benzylmercaptostyrenes (X) with hydrazine hydrate and phenylhydrazine gave 3(5)‐aryl‐5(3)‐phenylpyrazoles (XI) and 3‐aryl‐1,5‐diphenylpyrazoles (XIII), respectively. Reaction of aroylphenylacetylenes (1) with N ‐allylthiourea gave 1‐allyl‐4,6‐diaryl‐pyrimidine‐2‐thiones (XVI).