p-Toluenesulfonic acid monohydrate → 3-methoxy-1H-Pyrrole-2,5-dione

Participants

Reaction Steps

To a solution of 3,3-dimethoxypyrrolidine-2,5-dione (12.3 g, 77 mmol) in toluene (500 mL) was added TsOH·water (1.46 g, 7.7 mmol). A Dean Stark Trap was attached and the reaction mixture was refluxed overnight. TLC (petroleum ether/EtOAc=1/1) showed the reaction was complete. The mixture was concentrated and purified by column chromatography (from petroleum ether/EtOAc=2/1 to petroleum ether/EtOAc=1/1) to afford 3-methoxy-1H-pyrrole-2,5-dione (6.9 g, 70% yield) as an orange solid.

Provenance & Evidence