Cobalt-catalyzed light-induced aminocarbonylative polymerization of aryl halides toward semi-aromatic polyamides

Abstract

Semi-aromatic polyamides are a class of high-performance engineering plastics that combine the favorable mechanical properties of aliphatic polyamides with the enhanced thermal resistance of their fully aromatic counterparts. However, their synthesis typically relies on polycondensation of diamines and diacids, whereas catalytic approaches employing Earth-abundant metals for the preparation of these materials remain largely underexplored. Herein, we report a cobalt-catalyzed, light-induced aminocarbonylative polymerization strategy for the direct synthesis of semi-aromatic polyamides from aryl halides and aliphatic diamines under mild conditions. Utilizing commercially available Co₂(CO)₈ as the catalyst, this method exhibits broad substrate scope, enabling access to structurally novel polyamides. Incorporation of rigid cyclic motifs into the polymer backbone significantly enhances thermal performance, as evidenced by a systematic increase in glass transition temperature (T_g), reaching up to 137 °C higher than those of linear analogues. This study establishes a new synthetic platform for the efficient and sustainable construction of semi-aromatic polyamides from readily accessible building blocks using a non-precious metal catalyst.