PURPOSE: To obtain the titled compound in high purity and yield, by reacting an aniline having no phenolic hydroxyl group with a maleic anhydride in the presence of a phosphorus oxide in a specific solvent at a specific temperature, and distilling and recovering directly the solvent and then the product.
CONSTITUTION: A compound of the formula (R1WR5 are H, halogen, 1W6C alkyl, phenyl, 1W6C alkyl ether, phenoxy, COOH or NO2) is reacted with a maleic anhydride or a derivative thereof in the presence of a phosphorus oxide, e.g. phosphorus pentoxide, (dehydration and imide ring closing agent) in a solvent, e.g. a nitrogen-containing aprotic polar solvent such as N,N-dimethylformamide. capable of dissolving the above-mentioned oxide and the aimed compound N-phenylmaleimide, at 80W200°C temperature, and the solvent and then the aimed compound are recovered directly by distillation to give the aimed N- phenylmaleimide useful as a raw material for heat-resistant polymers, etc.
SUEYOSHI TADAHIRO
AYA TOSHIHIKO
