1979 Volume 99 Issue 10 Pages 1051-1054
Reaction of isoquinolinium bis (ethoxycarbonyl) methylide (1) with 2-butanone, cyclopentanone, and cyclohexanone gave ethyl 1, 2-dimethylpyrrolo [2, 1-a] isoquinoline-3-carboxylate (9), ethyl 10, 11-dihydro-9H-cyclopenta [3, 4] pyrrolo [2, 1-a] isoquinoline-8-carboxylate (10), and ethyl 9, 10, 11, 12-tetrahydroisoindolo [1, 2-a] isoquinoline-8-carboxylate (11), respectively. Similar reaction of isoquinolinium cyano (ethoxycarbonyl) methylide (12) with cyclopentanone and cyclohexanone gave 10, 11-dihydro-9H-cyclopenta [3, 4] pyrrolo [2, 1-a] isoquinoline-8-carbonitrile (13) and 9, 10, 11, 12-tetrahydroisoindolo [1, 2-a] isoquinoline-8-carbonitrile (14), respectively. Methylide (1) reacted with acetylacetone to give ethyl 2-methylpyrrolo [2, 1-a] isoquinoline-3-carboxylate (3) and ethyl 1-acetyl-2-methylpyrrolo [2, 1-a] isoquinoline-3-carboxylate (15). Similarly, compound 3 and ethyl 3-ethoxycarbonylpyrrolo [2, 1-a] isoquinoline-2-acetate (5) were obtained by the reaction of the methylide (1) with diethyl acetonedicarboxylate.
