118795-48-5Relevant articles and documents
Fission of 1,2,4-Thiadiazol-3-ones by Triphenylphosphane: Triphenylphosphonio Thioimidazolates and Their Consecutive Reactions
Tittelbach, Franz,Martin, Dieter
, p. 338 - 348 (2007/10/02)
Treatment of benzimidazothiadiazol-3(2H)-ones (1) and imidazothiadiazol-3(2H)-ones (17) with triphenylphosphan leads to the liberation of isocyanate and the formation of triphenylphosphonio-thiobenzimidazolat (4) and triphenylphosphonio-thioimidazolat (18), respectively. 2,4-Diphenyl-5-phenylimino-1,2,4-thiadiazol-3-one (23) is desulfurized with Ph3P and decomposed into phenyl isocyanate and diphenylcarbodiimide whereas the N-unsubstituted imino-thiadiazol-3-one (25) is attacked at the exocyclic imino group by Ph3P to give the N-phosphoranylidene thiourea (26).The structure of 4 can be rationalized as a dynamic system between polar and apolar valence isomeres.Reactions of 1 and 17 with cyanates, isocyanates, carbon disulfide, acetic anhydride, amines, benzyl chloride, grignard compounds, and CH acidic compounds are described.