Highly Efficient Solvent-free Conversion of CO<sub>2</sub> into Cyclic Carbonates by Acrylamide–KI
Qingshuo Li, Hao Yang, Mengqing Li, Kexin Zhao, Baogen Duan, Chen Zhang, Hongxia Wang, Congzhen Qiao, Haibo Chang, Tong Lin
Abstract
The cycloaddition of CO2 with epoxide has been a promising way to fix CO2. Developing efficient, low-cost catalysts for this reaction is highly desired. In this paper, we report a novel cocatalyst system that consists of acrylamide and KI for the synthesis of propylene carbonate using CO2 and propylene oxide as starting materials. Different amides (i.e., acrylamide, benzamide, nicotinamide, acetamide, N-isopropylacrylamide, N-tert-butylacrylamide, and N,N-dimethylacrylamide) were combined with different potassium halides to investigate their catalysis capability. KI/acrylamide showed the highest efficiency, and a synergetic effect occurred between acrylamide and KI. At the KI: acrylamide ratio of 1:1 (mol/mol) and concentration of 2.5 mol% for both of them (based on PO), the reaction reached a yield of 95.3%. The catalytic system applies to the cycloaddition reaction using different epoxides. The reaction mechanism was proposed.