Sustainable Synthesis of Quinazolinones through Boiler Flue Gas CO₂ Utilization via Pd@POP-1 Catalyst under Mild Conditions

A catalyst, Pd@POP-1, has been successfully synthesized by embedding palladium (Pd) nanoparticles into a nitrogen-rich porous organic polymer (POP) through the copolymerization of imidazole and triazine ionic salts with divinylbenzene. This catalyst features a unique imine (-C=N) structure within the triazine ring and multiple coupled imine groups, which significantly enhances CO2 adsorption efficiency and exhibits remarkable catalytic performance. At ambient pressure and mild temperatures, Pd@POP-1 effectively converts low-concentration CO2 (less than 15 vol.%) into quinazolinones, even in the presence of SO2 (up to 428 mg/m³) and NO2 (up to 221 mg/m³), achieving high yields. Remarkably, Pd@POP-1 also efficiently transforms CO2 from boiler flue gas, which contains 10 vol.% CO2, into quinazolinones with satisfactory yields. This approach not only provides an eco-friendly alternative for quinazolinone production by replacing phosgene with actual flue gas as a carbon source but also represents a promising strategy for the resource utilization of CO2 in flue gas.