Synthesis of cyclic carbonates by CO₂ cycloaddition with epoxides: recent advances, challenges and perspectives

The catalytic conversion of CO₂ into functionalized chemical products has evolved into a pivotal scientific frontier, garnering substantial research investment from multidisciplinary domains. Among diverse transformation pathways, the atomically economical cycloaddition between CO₂ and epoxides to synthesize cyclic carbonates stands out as a paradigm of sustainable synthesis, fully complying with green chemistry metrics and circular economy principles. These value-added cyclic carbonates serve as critical components in advanced energy storage systems (e.g., lithium-ion battery electrolytes), bioactive molecule synthesis, and specialty chemical production. This critical review systematically explores recent progress, technical barriers, and strategic directions within CO₂ cycloaddition research. The analysis commences with a mechanistic dissection of three predominant activation modes (CO₂ activation, epoxides activation, and dual activation), subsequently conducting comparative assessments of catalytic systems spanning molecular complexes to heterogeneous frameworks. A techno-economic evaluation is then presented regarding reactor configurations, including batch processing, continuous flow systems, and microchannel technologies. Notably, the work emphasizes an urgent need for innovative catalytic materials capable of dual-functionality: selective adsorption of dilute CO₂ streams from industrial flue gases or ambient air under mild conditions (25 °C, 1 atm), coupled with in situ catalytic transformation into target carbonates without intermediate separation. The proposed research matrix establishes theoretical foundations and practical guidelines for developing next-generation carbon capture-utilization integrated technologies.