Green and Facile Synthesis of New 3-(Phenylallylideneamino)indeno[1,2-d]imidazoles

Abstract

A green and facile strategy has been proposed for the synthesis of previously unknown 3a,8a-dihydroxy-3-[(3-phenylprop-2-en-1-ylidene)amino]-2-sulfanylidene-2,3,3a,8a-tetrahydro-1H-indeno[1,2-{und}]imidazol-8-one and 3a,8a-dihydroxy-3-[(3-phenylprop-2-en-1-ylidene)amino]-1,3,3a,8a-tetrahydroindeno[1,2-d]-imidazole-2,8-dione in excellent yields by condensation of cinnamaldehyde thiosemicarbazone and semicarbazone, respectively, with ninhydrin in boiling dioxane. The reaction is clean, simple, and free of work-up and column chromatography.