Synthesis of Spiro[benzo[g]chromene-4,3′-pyrroles] by Reaction of Pyrrolediones with Malononitrile and 2-Hydroxynaphthalene-1,4-dione

Abstract

One-pot reaction of ethyl 1-R-4,5-dioxo-2-phenyl-4,5-dihydro-1H-pyrrole-3-carboxylates with malononitrile and 2-hydroxynaphthalene-1,4-dione in boiling 1,4-dioxane in the presence of triethylamine afforded ethyl 1′-R-2-amino-3-cyano-2′,5,10-trioxo-5′-phenyl-1′,2′,5,10-tetrahydrospiro[benzo[g]chromene- 4,3′-pyrrole]-4′-carboxylates.