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

Participants

Reaction Steps

A maleic anhydride copolymer and an aminophenol are heated in an organic solvent such as dimethylformamide to 0°-150° C., preferably 10°-100° C., more preferably 50°-100° C. for 1-20 hours to convert a portion or whole of the maleic anhydride units into N-(hydroxyphenyl)maleamic acid unit. To the reaction mixture is added a tertiary amine catalyst, and is further added an azeotropic agent (i.e., azeotropic solvent) such as toluene or xylene for removing water produced upon cyclization-dehydration reaction. The resulting mixture is then heated to 80°-200° C., preferably 100°-150° C., for 1-20 hours for performing a cyclization-dehydration reaction, to obtain the desired N-(hydroxyphenyl)maleimide copolymer.

Provenance & Evidence