Synthesis of some 5-methyl-4-(diazo-4-(heteroaryl) phenyl)-pyrazolone derivatives

A group of α, β unsaturated carbonyl compounds, as intermediates were prepared by diazotization of para amino acetophenone, coupling followed by cyclization with hydrazine derivatives. The hetero aryl methyl ketones upon reaction with aromatic aldehydes under basic condition, furnished the corresponding α, β unsaturated carbonyl compounds. These intermediates were allowed to cyclize with hydrazine derivatives, hydroxyl amine and thiourea to formpyrazole, isoxazole and thiopyrimidine derivatives respectively. The structures of synthesized compounds were confirmed by IR, UV, (1H, 13C) –NMR and MS