Preparation of spirooxindoles catalyzed by nano-Co3S4 under microwave irradiations

Abstract

An efficient and rapid method is used for the synthesis of 10-methyl-8 H-spiro[benzo[5,6]chromeno[2,3- c]pyrazole-11,3′-indol]-2′(1′ H)-one and 8-methyl-10-phenyl-10,11-dihydrospiro[pyrazolo[3,4- b]benzo[ h]quinolin-7,3′-indol]-2′(1′ H)-one by a four-component reactions of phenylhydrazine or hydrazine hydrate, isatins, ketoesters, and naphthylamine or 2-naphthol using nano-Co3S4 under microwave irradiation.