Abstract

Florence Isabirye Muranga

Reaction of 4-acetyl-5,6-diphenylpyridazin-3(2H)-one (1) with diethyl oxalate in refluxing sodium ethoxide/ethanol mixture afforded ethyl 2,4-dioxo -4-(3-oxo- 5,6-diphenyl-2,3-dihydropyridazin4- yl)butanoate (2) which with hydrazine hydrate (1:1 mol) in refluxing ethanol afforded ethyl5- (3-oxo-5,6- diphenyl-2,3-dihydropyridazin 4- yl)-1H-pyrazole-3-carboxylate (3) while reaction of 2 with hydrazine hydrate (1:2 moles) in refluxing ethanol gave the corresponding acid hydrazide (4) . Reaction of acid chloride (6) with primary amines namely, aniline, p-toluidine and anisidine in the presence of DMF containing K2CO3 afforded the corresponding amide derivatives (7a – c). Hydrazones (9a – c) were prepared via the reaction of the acid hydrazide (4) with appropriate aldehydes namely, benzaldehyde, pchlorobenzaldehyde and p-nitrobenzaldehyde in refluxing ethanol/acetic acid mixture. Reaction of carboxylic acid hydrazide (4) with each of ethyl acetoacetate, acetylacetone and ethyl cyanoacetate gave the corresponding pyrazolone and pyrazole derivatives 11, 12 and 13 respectively.