Synthesis of N-phenylmaleimide with Using Vitamin B1 as Catalyst

N-phenylmaleimide was synthesized from aniline and maleic anhydride with vitamin B1 as catalyst and acetic anhydride as dehydrant in acetone solvent by two-step method(acetic anhydride method).By means of optimizing the technological methods such as the concentration of catalyst,reaction time and the ratio of acetic anhydride as dehydrant to maleic anhydride,the optimal conditions were confirmed.The results of the experiments showed that the vitamin B1 used as catalyst gained a nice result.The optimum reaction conditions were listed as follows: the molar ratio of acetic anhydride as dehydrant to maleic anhydride was 1.6∶1,the reaction time was 4h and the concentration of catalyst was 1.5% of mass of maleic anhydride.Under these conditions,the yield of product was up to 63.2%.And the reusage test of acetone solvent showed that it had excellent reusage stability.