Skeleton Carbonylation of Conjugated Microporous Polymers by Osmium Catalysis for Amine-Rich Functionalization.

This work introduces a new efficient method for the postsynthetic modification of conjugated microporous polymers (CMPs). Osmium catalysis of hollow CMP (H-CMP) in the presence of NaClO resulted in the conversion of alkynes in the skeleton of CMPs to dicarbonyl groups to form H-CMP-DC. Through controlling the reaction time, the carbonylation degree of H-CMP could be managed, maintaining hollow morphology. We verified the benefits of carbonyl groups in H-CMP-DC in the removal of Cr(VI) from water. Imination of H-CMP-DC resulted in amine-rich H-CMP (H-CMP-A), which showed enhanced adsorption performance toward Cr(VI) in water with up to 73 mg/g, compared with the H-CMP and H-CMP-DC. The H-CMP-A could be recycled at least five times, maintaining its original adsorption ability.