Methylated nitrogen-substituted ) was demonstrated to catalyze cyclic carbonate synthesis using β,γ-unsaturated alcohol and CO2. The methylated nitrogen in the framework acts as the catalytic active site. The turnover frequency (TOF) as function of CO2 partial pressure and β,γ-unsaturated alcohol concentration reflected the major active surface species. The CO2 dependence could be explained by the adsorption equilibrium of CO2 over the active site. The formation of carbamate species is the key

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... o this reaction. Less β,γ-unsaturated alcohol is adsorbed on the catalytic site than CO2. The reaction could involve the following five steps; carbamate formation, interaction of β,γ-unsaturated alcohol with the carbamate species, deprotonation and associated C _ O bond formation, intramolecular cyclization, and desorption of the unsaturated cyclic carbonate. Compared with cyclic carbonate synthesis from cyclic ether, the difference in pressure dependence of the cyclic carbonate syntheses could be explained by the competing adsorption (or activation) of the counter reactants with CO2. The adsorption of β,γ-unsaturated alcohol on the methylated nitrogen is much less than that of cyclic ether.