120811-68-9Relevant academic research and scientific papers
Ring-Opening Reaction of 1,3,4-Oxadiazolone and 1,3,4-Oxadiazolinethione: Reaction of 2-Phenyl-1,3,4-oxadiazolin-5-one and 2-Phenyl-1,3,4-oxadiazoline-5-thione with Amines
Saegusa, Yasuo,Harada, Shigeo,Nakamura, Shigeo
, p. 1337 - 1342 (2007/10/02)
The ring-opening abilities of amines toward 1,3,4-oxadiazolines, 2-phenyl-1,3,4-oxadiazolin-5-one (1a) and 2-phenyl-1,3,4-oxadiazoline-5-thione (1b), were investigated with relation to their basicities or pKb values.Oxadiazolines 1a and 1b were easily reacted with amines such as benzylamine and aniline, but not with p-nitroaniline, to form the corresponding ring-opening adducts.The reactions of both 1a and 1b with o-phenylenediamine produced benzodiazoles with the liberation of benzoylhydrazide, whereas the reactions with o-aminobenzamide furnished quinazolines with the liberation of ammonia. o-Aminophenol and o-aminothiophenol were also reacted with 1a and 1b both of them giving 1,5-dibenzoylcarbohydrazide from 1a and 1,2-dibenzoylhydrazine from 1b.From the conditions affording the corresponding ring-opening adducts or reaction products, the ring-opening abilities of the amines toward 1a and 1b are in good correlation with the strength of their basicities or pKb values.The ring-opening of oxadiazolines were proved to occur with anilines.Therefore, the other reactions are also supposed to proceed via the ring-opening steps.
