A phenoxazine-based covalent triazine framework was prepared via a one-step trimerization and exhibited good photocatalytic performance, excellent recyclability and wide substrate scope in the aerobic hydroxylation of arylboronic acids to phenols.

The Friedel–Crafts alkylation strategy was used to prepare a hypercrosslinked polymer catalyst, which showed superior performance towards the cycloaddition reaction of CO₂ with epoxides.