Organic reactions in the aqueous medium Part-IX Effect of sonication on the reaction of ethyl acetoacetate with hydrazine derivatives

The reactions of ethyl acetoacetate with semicarbazide hydrochloride and hydrazine monohydrate in the aqueous medium by stirring at room temperature and under sonication have bren studied. The parameters for the formation of ethyl acetoacetate semicarbazone (1), 3-methylprazol-5-one-1-carboxamide (II), 3-methylpyrazol-5-one (III), and hydrazine-1,2-diamide have been determined. It has been observed that stirring at room temperature leads to the formation of (I) or (II), while sonication yields (III) as well, depending upon the reaction parameters. Moreover, improved yields of these products are obtained in a considerably shorter time under sonication. However. (IV) is obtained only by boiling the reactants under mild reflux. A plausible reaction scheme for the formation of different products has also been suggested.

C M ASHRAF ,SHAFI ULLAH KHAN ,S SHAUKAT ALI ,