Conjugated microporous polymers using a copper-catalyzed [4 + 2] cyclobenzannulation reaction: promising materials for iodine and dye adsorption

A design strategy is disclosed to synthesize conjugated microporous polymers (CMPs) using a versatile copper-catalyzed [4 + 2] cyclobenzannulation reaction, which employs a diphenylethynyl terephthalaldehyde derivative 3 with a series of triptycene-based diethynyl aryl building blocks 2a-e. Investigation of the intrinsic microporosity properties of CBP1-5 using nitrogen adsorption measurements reveals Brunauer-Emmett-Teller (BET) surface areas up to 794 m2 g-1 and average pore volumes reaching 0.63 cm3 g-1. Inspection of the adsorption properties of the graphitic-like polymers CBP1-5 divulges their high iodine uptake with a maximum of 166 wt%. Moreover, the target polymers CBP1-5 prove their efficiency as selective dye adsorbents by removing up to 100% methylene blue over methyl orange from aqueous solution.