314748-14-6Relevant articles and documents
A challenging synthesis of new 1,3,4-thiadiazole derivatives starting from 2-acylamino-3,3-dichloroacrylonitriles
Golovchenko, Oleksandr V.,Pilyo, Stepan G.,Brovarets, Vladimir S.,Chernega, Alexander N.,Drach, Boris S.
, p. 454 - 458 (2007/10/03)
Available 2-acylamino-3,3-dichloro-acrylonitriles, when treated with hydrazine hydrate, provide 2-alkyl- or 2-aryl-5-hydrazino-1,3-oxazole-4- carbonitriles that readily add alkyl or aryl isothio-cyanates and the adducts formed recyclize on heating. Finally, the synthesis results in 5-alkyl(aryl)amino-1,3,4-thiadiazol-2-yl(acylamino)acetonitriles or the products of their further cyclization, 2-(5-amino-1,3-oxazol-2-yl)-1,3,4-thiadiazole derivatives. The structures of the novel substituted 1,3,4-thiadiazoles are corroborated spectroscopically as well as by X-ray diffraction method.
Recyclization of 2-aryl-4-cyano-5-hydrazinooxazoles
Pil'o,Brovarets,Vinogradova,Chernega,Drach
, p. 280 - 285 (2007/10/03)
The available 2-benzoylamino-3,3-dichloroacrylonitrile and its analogs when treated with excess hydrazine hydrate convert to 2-aryl-4-cyano-5-hydrazinooxazoles. The products are fairly stable in usual conditions but undergo recyclization on heating in acetic acid to give previously unknown derivatives of 2-methyl-1,3,4-oxadiazole with a 5-acylamino(carbamoyl)methyl substituent, whose structure was established by spectroscopy and X-ray diffraction. An important role in this complex transformation is probably played by prototropic forms of 4-cyano-5-hydrazinooxazoles, viz. hydrazones of substituted 2-oxazolin-5-ones which are not aromatic and thus can be cleaved with acetic acid and then recyclize.
