A new method of synthesis of 1,3,4-oxadiazoles from aromatic acids and semicarbazide with polyphosphoric acid was written by Ren, Zhong-Jiao;Jiang, E.;Zhou, Hong-Bin. And the article was included in Youji Huaxue in 1995.Application of 15420-02-7 This article mentions the following:
Oxadiazoles I (R = Ph, substituted Ph, 3-pyridyl, 4-pyridyl) were prepared in 41-95% yield by stirring RCO2H with semicarbazide hydrochloride and polyphosphoric acid at 150-160° for 1 h. In the experiment, the researchers used many compounds, for example, 2,5-Di(pyridin-4-yl)-1,3,4-oxadiazole (cas: 15420-02-7Application of 15420-02-7).
2,5-Di(pyridin-4-yl)-1,3,4-oxadiazole (cas: 15420-02-7) belongs to pyridine derivatives. Pyridine is diamagnetic and has a diamagnetic susceptibility of −48.7 × 10−6 cm3·mol−1.The molecular electric dipole moment is 2.2 debyes. The standard enthalpy of formation is 100.2 kJ·mol−1 in the liquid phase and 140.4 kJ·mol−1 in the gas phase. Halopyridines are particularly attractive synthetic building blocks in a variety of cross-coupling methods, including the Suzuki-Miyaura cross-coupling reaction.Application of 15420-02-7