Porous Poly(aryleneethynylene) Networks through Alkyne Metathesis

Abstract

The development of new synthetic methods has been a central challenge in the field of organic porous materials. Herein, we present the first application of alkyne metathesis to the synthesis of highly porous poly(aryleneethynylene) (PAE) networks. The permanent porosity of as-synthesized PAEs was confirmed by N2 adsorption/desorption studies, and high Brunauer–Emmett–Teller (BET) specific surface areas (P/P0 = 0.01–0.1) up to 2312 m2·g–1 were observed. PAE networks with the same chemical connectivity were also prepared through palladium-catalyzed Sonogashira cross-coupling under otherwise similar reaction conditions. The networks prepared through alkyne metathesis at three different temperatures (40 °C, 55 °C, and 75 °C) consistently exhibit a higher specific surface area and higher thermal stability, suggesting alkyne metathesis is advantageous in the preparation of highly porous organic materials. Our study demonstrates the feasibility of employing alkyne metathesis in the preparation of porous polymer networks and serves to expand the synthetic tool box for this emerging class of porous materials.