1,3,4-Oxadiazole is a thermally stable and neutral Heteroaromatic molecule having a wide variety of uses, particularly as biologically active compounds in medicine, agriculture, dye stuffs, UV absorbing and fluorescent materials, heat resistant polymers and scintillators. Oxadiazoles and their analogues can be considered as simple five membered heterocycles possessing one oxygen and two nitrogen atoms1-6. The oxadiazole exists in different isomeric forms such as 1,3,4- oxadiazole, 1,2,5-oxadiazole, 1,2,4-oxadiazole, and 1,2,3-oxadiazole, out of which 1,3,4-Oxadiazole is a thermally stable neutral aromatic molecule and its estimated resonance energy is 167.4 kJ/mol. particularly, aryl group at position 2 increases the thermal stability of 1,3,4-oxadiazole. The ring is stable to heat, a property which has been exploited in the production of heat-resistant poly-1,3,4-oxadiazoles. UV spectra of substituted 1,3,4-oxadiazoles are similar to those of substituted benzenes, particularly in the case of 2-phenyl-1,3,4-oxadiazoles7-18 (?max in ethanol = 247.5 nm, log ? 4.26).
