Porphyrinic metal–organic frameworks (PMOFs) as catalysts in CO2–epoxide coupling toward cyclic carbonate synthesis: Recent advances and future perspectives

Rising atmospheric CO2 levels are driving critical ecological issues worldwide, and if no remedy is implemented, they will exert adverse effects on human populations and the biosphere. Elevated CO2 levels lead to global warming, climate disruptions that affect the environment, change the conditions for plant reproduction, and create frequent associated problems. Therefore, significantly reducing atmospheric CO2 levels is vital. One promising approach to achieving this aim involves the coupling of CO2 with epoxides to produce cyclic carbonates, which is being extensively explored in laboratories worldwide. However, the fixation reaction of CO2 remains challenging because of its thermodynamic stability and poor reactivity, prompting the development of innovative heterogeneous catalysts. Porphyrins and metalloporphyrins have emerged as talented catalysts for various catalytic conversions, including CO2 reduction, water splitting, and CO2 transformation. Unfortunately, the performance of porphyrin structures as catalysts is often limited by their low rigidity and tendency to self-aggregate. To overcome these aggregation-related limitations, researchers are transforming monomeric units into expanded two- or three-dimensional (2D/3D) networks. This strategy enhances catalytic efficiency and diversifies the range of possible uses for these materials. Porphyrinic metal-organic frameworks (PMOFs) have emerged as promising candidates for the catalytic transformation of CO2 because of their exceptional qualities, which include high porosity, large surface area, robustness, and structural stability that impart a great affinity for CO2 molecules. This review emphasizes PMOFs by outlining their synthetic methodologies and underscoring their role in enhancing catalytic efficiency in CO2 utilization. Consequently, it seeks to provide researchers with valuable insights into exploiting the potential of PMOF materials for developing high-performance catalysts that deliver excellent selectivity, yield, and conversion in CO2–epoxide coupling reactions for cyclic carbonate synthesis.