Synthesis and characterization of 5(3)-aryl-1H-3(5)-substituted pyrazole hydrazones derivatives

Ethyl 5(3)-(4-methoxyphenyl)-1H-pyrazole-3(5)carboxylate were synthesized through Claisen condensation,Knorr cyclization with 1-(4-methoxyphenyl)ethanone and diethyl oxalate as the starting materials.This compound reacted with hydrazine hydrate to obtain 5(3)-(4-methoxyphenyl)-1H-pyrazole-3(5)-carbohydrazide,which further reacted with the corresponding aromatic aldehyde.Them,ten new 5(3)-aryl-1H-3(5)-substituted pyrazole hydrazones compounds were obtained and the structure of all the new compounds were characterized by elemental analysis,infrared spectrum and 1H NMR.