A novel route to polyimides via polyamic aryl amides

Summary A new synthetic route to polyimides was studied on monofunctional model compounds by the reaction of various 4-substituted phenyl-phthalisoimides with paratoluidine to form asymmetrically substituted diphthalamides followed by thermal cyclization to phthalimide. Both steps of the preparation pathway were kinetically explored. It was determined that the first step is governed by second order constants directly dependent upon the pK_a of the amine used to prepare the beginning isoimide as well as the regioselectivity of the last step.