Spiro-condensation of 5-methoxycarbonyl-1: H -pyrrole-2,3-diones with cyclic enoles to form spiro substituted furo[3,2- c] -coumarins and quinolines

Abstract

Highly efficient spiro-condensation enabling cyclic enoles to act as 1,3-bis-nucleophiles in reaction with pyrrole-2,3-diones acting as 1,2-bis-electrophiles was developed. The corresponding furo[3,2-c]coumarins and furo[3,2-c]quinolines containing a spiro pyrrole fragment were obtained in high yields