Versatile Porous Poly(arylene ether)s via Pd-Catalyzed C-O Polycondensation

Porous organic polymers (POPs) with strong covalent linkages between various rigid aromatic structural units having different geometries and topologies are reported. With inherent porosity, predictable structure, and tunable functionality, POPs have found utility in gas separation, heterogeneous catalysis, sensing, and water treatment. Poly(arylene ether)s (PAEs) are a family of high-performance thermoplastic materials with high glass-transition temperatures, exceptional thermal stability, robust mechanical properties, and excellent chemical resistance. These properties are desirable for development of durable POPs. However, the synthetic methodology for the preparation of these polymers has been mainly limited in scope to monomers capable of undergoing nucleophilic aromatic substitution (S_NAr) reactions. Herein, we describe a new general method using Pd-catalyzed C-O polycondensation reactions for the synthesis of PAEs. A wide range of new compositions and PAE architectures are now readily available using monomers with unactivated aryl chlorides and bromides. Specifically, monomers with conformational rigidity and intrinsic internal free volume are now used to create porous organic polymers with high molecular weight, good thermal stability, and porosity. The reported porous PAEs are solution processable and can be used in environmentally relevant applications including heavy-metal-ion sensing and capture.