Facile Synthesis of Spiro[indane-2,1′-pyrrolo[2,1-a]isoquinolines] via Three-Component Reaction of Isoquinolinium Salts, Indane-1,3-dione, and Isatins

Abstract

A series of novel 2′-aryl-2′-(2-oxo-1,2-dihydro-3<i>H</i>-indol-3-ylidene)-2′,3′-dihydro-10b′<i>H</i>-spiro[indene-2,1′-pyrrolo[2,1-<i>a</i>]isoquinoline]-1,3-diones were efficiently synthesized by three-component reactions of in situ generated <i>N</i>-phenacylisoquinolinium bromides with indane-1,3-dione and isatins in ethanol with triethylamine as the base. A domino reaction mechanism for the formation of the spiro compounds was rationally proposed.