4-Aminophenol → 1-(4-hydroxyphenyl)-1H-pyrrole-2,5-dione

Participants

Reaction Conditions

Reaction Steps

In a reactor, 30.0 g (0.275 moles) of p-aminophenol, 29.7 g (0.303 moles) of maleic anhydride, 39.0 g (0.275 moles) of phosphorus pentoxide and 100 g of dimethylformamide were charged and stirred at 15° C. for 2 hours. The reaction mixture was then gradually heated to 60° C., at which temperature the reaction was further continued for 2.5 hours. After cooling to room temperature, the resulting reaction mixture was admixed with water to precipitate N-(p-hydroxyphenyl) maleimide in the form of crystals. The crystals were separated by filtration, washed with water and then dried to obtain 25.1 g (0.133 moles) of N-(p-hydroxyphenyl) maleimide (yield 48.2%).

Provenance & Evidence