AlCl 3 -catalyzed chemoselective cascade reactions of 4-anilinocoumarins with 2-furylcarbinols: access to densely functionalized chromeno[4,3- b ]pyrrol-4(1 H )-one derivatives.

An unprecedented protocol has been developed for the preparation of highly functionalized chromeno[4,3- b ]pyrrol-4(1 H )-ones, which are not only valuable architectures of many biologically active molecules but also key building blocks for rich photophysical properties. The transformation proceeded through chemoselective intermolecular α-carbon nucleophilic attacking/ring-opening/Michael addition/deprotonation aromatization processes from 4-aminocoumarins and 2-furylcarbinols.