Zinc-Accelerated Cycloaddition of Carbon Dioxide to Styrene Oxide Catalyzed by Pyrrolidinopyridinium Iodides

摘要

The addition of Znl2 drastically accelerated the cycloaddition of carbon dioxide to styrene oxide catalyzed by pyrrolidinopyridinium iodides. In the presence of Znl2, the styrene carbonate yield reached up to 89 % in 7 h at 100 °C under 1 arm of CO2. The rate constant increased by greater than three-fold by the addition of Znl2. Studies of reaction kinetics in addition to high resolution mass and NMR analysis demonstrated that the primary active species consists of two or more pyrrolidinopyridinium cations combined with Znl4~(2-) anion.