反应详情

温度

70 °C

Polyphosphoric acid (20 g) and P2O5 (1.0 g) were mixed together and heated at 70° C. for 20 min. To the mixture was added 3-(4-ethoxycarbonyl-5-methyl-3-pyrrolyl)propanoic acid (1.0 g, 4.44 mmol) and heating was continued for 20 hours. The reaction was poured into ice-water, extracted with EtOAc. The organic layer was washed with brine and sat. NaHCO3, and dried (MgSO4). After removal of the solvent, the crude product was recrystallized from CH2CI2-hexane to give (0.78 g, 85%) of 2-methyl-6-oxo-1,4,5,6-tetrahydro-cyclopenta[b]pyrrole-3-carboxylic acid ethyl ester as a white solid.

1. temperatureheating
2. extractionextracted with EtOAc
3. washThe organic layer was washed with brine and sat. NaHCO3
4. dry with materialdried (MgSO4)
5. customAfter removal of the solvent
6. customthe crude product was recrystallized from CH2CI2-hexane