A Sustainable Pathway for CO2 Utilization: Pd(II)-Embedded Diamino-Functionalized Al(III) MOF Catalyst with High CO2 Sorption Affinity Enabling Recyclable Synthesis of Bioactive Quinazolinones under Atmospheric Pressure Conditions

Quinazolinone derivatives are an important class of nitrogen-containing heterocycles that serve as key intermediates in the synthesis of biologically active compounds. Sustainable synthesis of such heterocyclic compounds via CO2 utilization represents an attractive strategy. Herein, we report the design, synthesis, and application of a Pd(II)-embedded, aluminum-based diamino-functionalized metal-organic framework (MOF) catalyst for the synthesis of quinazolinones. The catalyst displayed high surface area (1048 m2/g), CO2 uptake (102 cc·g-1, 1 bar, 0 °C), isosteric heat of CO2 adsorption (25.8 kJ/mol), and CO2/N2 selectivity (17.5). It enabled effective cyclization of CO2, 2-haloanilines, and isocyanides under atmospheric CO2 pressure at 80 °C for 8 h in the presence of a base in ACN, affording bioactive quinazolinone derivatives in high yields (93%). This activity is attributed to the synergistic effects of the confined porous architecture, improved CO2 adsorption capacity, and stabilization of active Pd(II) species in the framework. The catalyst showed excellent recyclability, structural stability over multiple cycles, and broad substrate compatibility with high functional group tolerance, affording 56%-90% yields. The catalyst also enabled large-scale synthesis of quinazolinone, highlighting its practical applicability for the synthesis of biologically active compounds. This study presents a sustainable strategy for transforming CO2 into pharmaceutically active heterocyclic compounds.