Reactions of zinc enolates formed from 2,2-dibromoindan-1-one or 2,2-dibromo-3,4-dihydronaphthalen-1(2H)-one and zinc with alkyl 5,5-dimethyl-2-oxo-2,5-dihydrofuran-3-carboxylates

Abstract

Reactions of derivatives of 3-aryl-2-cyanopropenoic acid with zinc enolates obtained from dibromotetralone or dibromoindanone and zinc are known to result in substituted spirocyclopropanes [1]. Boiling of alkyl 5,5-dimethyl-2-oxo-2,5-dihydrofuran3-carboxylates Ia, Ib in a mixture ether–ethyl acetate for 40 min with zinc enolates II, III obtained by the reaction of 2,2-dibromoindan-1-one or 2,2-dibromo-3,4-dihydronaphthalen-1(2H)-one with zink afforded in good yields