Unprecedented formation of spiro[indoline-3,7′-pyrrolo[1,2-a]azepine] from multicomponent reaction of l -proline, isatin and but-2-ynedioate

Spiro[indoline-3,3′-pyrrolizines] and spiro[indoline-3,7′-pyrrolo[1,2-a]azepines] can be selectively produced from three-component reaction of α-amino acids, isatins and but-2-ynedioates.