Photochemical N‑Formylation\nof Amines and Cyclic\nCarbonate Synthesis from Epoxides by the Use of Light-Mediated Fixation\nof Carbon Dioxide Using Covalent Organic Framework/g‑C<sub>3</sub>N<sub>4</sub> Composites

A proficient\nheterogeneous catalytic system for the photocatalytic\nN-formylation reaction of amines and cyclic carbonate synthesis from\nepoxides using CO<sub>2</sub> as a carbon source under ambient reaction\nconditions has been documented. A sophisticated approach has been\nestablished for the current photocatalytic process, aiming for the\nsuccessful production of formamides and cyclic carbonates with high\nlevels of selectivity and efficiency by adjusting several variables\nsuch as the solvent, time, as well as light source involved in the\nreaction. We have synthesized two distinct catalysts, T-COF and N-COF,\nalong with the g-C<sub>3</sub>N<sub>4</sub> heterojunction, demonstrating\noutstanding photocatalytic performance. Compared to g-C<sub>3</sub>N<sub>4</sub>@N-COF, the g-C<sub>3</sub>N<sub>4</sub>@T-COF photocatalyst\nshowed significantly better catalytic efficiency in the light-driven\nformation of cyclic carbonates and formamides using CO<sub>2</sub> under other suitable reaction conditions at room temperature. The\ng-C<sub>3</sub>N<sub>4</sub>@COF photocatalysts can be recycled and\nused multiple times without any noticeable decrease in the efficiency.