Patent ID: 8283477
Filing Date: 2012-10-09
Classification: C07D

Abstract:
1. A method of preparing N-substituted maleimide in high purity and high yield, the method comprising: introducing an organic solvent; an acid catalyst; polyalkylene glycol having a molecular weight of 1.000-10.000 as a catalyst binder; a dehydration co-catalyst selected from the group consisting of oxides, acetates, maleates, succinates, and chlorides with at least one metal selected from the group consisting a zinc (Zn), chromium (Cr), palladium (Pd), cobalt (Co), nickel (Ni), iron (Fe), and aluminum (Al); and a stabilizer into a reactor; introducing a primary amine into the reactor to form an amine salt; introducing maleic anhydride into the reactor; and subjecting the resulting mixture to a dehydration-cyclization reaction, wherein water produced during the reaction is azeotropically distilled.