Hydrochloric Acid → HCID 13575822, compound

Participants

Reaction Steps

To a suspension of ethyl α-cyano-5,6-dihydro-2-oxo-Δ1,α -4H-pyrrolo[3,2,1-ij]quinolineacetate (8.47 g, 0.03 mole) in methanol (30 ml) was added potassium cyanide (2.93 g, 0.04 mole) and the mixture was stirred for 3 hours room temperature. The resultant solution was cooled to 0° C., saturated with hydrogen chloride gas and allowed to stand overnight. The mixture was warmed at 50° C. for an hour and refluxed for 4 hours. After cooling, an addition of water (30 ml) gave a viscous tar containing 4-methoxycarbonyl-5',6'-dihydrospiro[pyrrolidine-3,1'-[4H]pyrrolo[3,2,1-ij]quinoline]-2,2',5(1'H)-trione, which was extracted with benzene, washed with water and dried. Evaporation of the benzene afforded yellow oily residue, to which was added 40 ml of acetic acid and refluxed for 10 hours. After evaporation of the solvent, the residue was treated with benzene to give a fine solid. Recrystallization from ethanol yielded 2.92 g (38.0%) of 5',6'-dihydrospiro[pyrrolidine-3,1'-[4H]pyrrolo[3,2,1-ij]quinoline]-2,2',5(1'H)-trione, as colorless needles, mp. 253°-255° C.

Provenance & Evidence