Ionic Liquid as an Efficient Promoting Medium for Fixation of CO₂:  Clean Synthesis of α-Methylene Cyclic Carbonates from CO₂ and Propargyl Alcohols Catalyzed by Metal Salts under Mild Conditions

Reactions of propargylic alcohols with CO(2) in a [BMIm][PhSO(3)]/CuCl catalytic system to produce the corresponding alpha-methylene cyclic carbonates were conducted with high yields. Mild reaction conditions, enhanced rates, improved yields, and recyclable ionic liquid catalyst systems are the remarkable features exhibited in this process. Furthermore, the use of large amounts of tertiary amines as well as nitrogen-containing organic solvent as employed in previously studies was avoided.