An efficient synthesis of pyrrolo[2,1-a]isoquinoline derivatives containing coumarin skeletons via a one-pot, three-component reaction

New dialkyl 3-(2-oxo-2H-3-chromenylcarbonyl)pyrrolo[2,1-a]isoquinoline-1,2-dicarboxylate derivatives were prepared by the reaction of 3-(2-bromoacetyl)coumarins, isoquinoline, and dialkyl acetylenedicarboxylates in the presence of triethylamine. This protocol has some advantages such as easy purification, easy performance, and good yields. The structures were confirmed spectroscopically (IR, 1H- and 13C-NMR, and EI-MS) and by elemental analyses. A plausible mechanism for this reaction is proposed (Scheme 2).