Aminophenols were allowed to react with maleic and phthalic anhydrides, producing high yields of the corresponding N-(hydroxyphenyl) maleamic and phthalamic acids, respectively. The amic acids were dehydrated to the corresponding maleisoimides and phthalisoimides with N,N-dicyclohexylcarbodiimide or ethyl chloroformate as the dehydrating agent. Formaldehyde was allowed to react with the products in the presence of an acid catalyst, and novel phenol formaldehyde resins (Novolac-like) were produced. The resins on treatment with a sodium carbonate solution or on prolonged heating at 50 degrees C suffered rearrangement to corresponding phenol formaldehyde resins with pendant imides. This rearrangement was accompanied by an increase in the softening point and thermal stability.