Systematic investigation of the role of the epoxides as substrates for CO2 capture in the cycloaddition reaction catalysed by ascorbic acid†

Abstract

This work establishes a comprehensive theoretical framework for synthesizing cyclic organic carbonates, crucial for the polymer industry, through the organocatalytic cycloaddition of carbon dioxide (CO₂) to epoxides under mild pressure and temperature conditions. Using advanced computational techniques, the study examines the thermodynamic and kinetic aspects of the reaction, with a particular focus on epoxide substrates featuring diverse substituents. Detailed analysis reveals activation energy barriers and identifies the rate-determining step (rds), offering crucial insights into the molecular processes governing the reaction. An automated data-driven workflow revealed that the buried volume of the epoxide O atoms was among the most influential molecular features affecting reaction barriers. Overall, the findings align with experimental data, offering insights into substrate design for optimized CO₂ utilization. This work calls for a systematic exploration of ascorbic acid-based catalyst modifications to optimize energy barriers and improve overall reaction performance, paving the way for rational catalyst design and predictive catalysis in CO₂ valorization. The computational study is not limited to basic research or ascorbic acid but is applicable to most catalysts capable of carrying out this reaction in the polymer industry.

Keywords: Epoxide; CO₂ activation; Sustainable catalysis; Data-driven workflows; DFT calculations; Predictive catalysis; Cycloaddition.