Abstract
(1,3-Dioxo-2,3-dihydro-[H-inden-2-ylidene)propanedinitrile (2, in dimethylformamide solution), 3-(dicyanomethylene)-2-indolone (3, in ethanol/piperidine solution) act on substituted carbohydrazides 1a-e forming the derivatives of oxidiazolylideneindene-1,3-diones 4a-e, spiro(indene-2,2'-oxadiazole)-1,3-dione 5a-e, cyloxoindenopyrazolecarbonitriles 6a-e, spiro(indoline-3,2'-oxadiazol)-2-ones 11a-e, and acylpyrazoloindoles 13a-e. Rational for these conversions involving the nucleophilic addition oil the dicyanomethylene carbon atom are presented.