Novel Synthesis of Linear Polyimides by Palladium-Catalyzed Carbonylation Polycondensation of Aromatic Diamides, Aromatic Dibromides, and Carbon Monoxide

A new and convenient method was found for the synthesis of linear imides by the palladium-catalyzed carbonylation condensation of aromatic amides with aromatic bromides and carbon monoxide. By the extension of this reaction to polymerization, a novel approach to the preparation of linear polyimides was developed. The effects of polymerization conditions, such as kinds and amounts of base and palladium catalyst, and polymerization temperature are discussed in detail. Large excess PPh3 was required to obtain a homogeneous solution. The reactivity of aromatic diamides was found to be low for this carbonylation polycondensation.