Prof. Dr. Ehab Abdel-LatifProf. Dr. Mohamed A. Ismail2026-01-272026-01-27https://dspace.academy.edu.ly/handle/123456789/1897Synthesis of different pyridine derivatives The cyclization of 1 was achieved in different solvents using several catalysts under various conditions to yield triazolopyridines 2 (R1 = H, OMe, F, Cl, Br or NO2). Under different reaction conditions, many catalysts like I2 / DMSO, AgNO3 / Na2S2O8, RuCl3 / TBHP, RuCl3 / Oxone, DDQ, CAN, Na2S2O8, Oxone, Fe and Cu complexes were screened [2].Heterocyclic six membered ring that obtained by replacing one –CHgroup of benzene by a nitrogen atom is known as pyridine, with the molecular formula C5H5N. As in benzene, the molecule is planar and follows Hückel rule as well as six π-electrons of the ring are in conjugated system and are delocalized over the heterocyclic ring. In the field of heterocyclic chemistry [1], compounds containing pyridine ring and its derivatives are widely used for many medicinal applications as listed below.SYNTHESIS OF SOME NEW CHLOROPYRIDINE