| Abstract: | Cyclopentanone condensed with phenylhydrazones 5 , or oximes 6 , in the presence of zinc dust, sodium propionate and propionic acid at 150° to give cyclopentab]pyrroles 7 in good yields. This chemistry was extended to the synthesis of pyrrolic products from 1-indanone, 2-indanone and 2-methylcyclopentanone. Benzyl 3-methylcyclopentab]pyrrole-2-carboxylate was found to react regioselectively with lead tetraacetate to give the corresponding 6-acetoxy derivative and subsequent acid-catalyzed condensations with 5-unsubsti-tuted pyrrole-2-carboxylates afforded a series of synthetically valuable dipyrroles 18a-c. |
