Bifunctional phase-transfer catalysts for fixation of CO₂ with epoxides under ambient pressure

Abstract

A series of bifunctional phase-transfer catalysts with a quaternary onium center and a hydrogen-bonding donor group were prepared for the fixation of CO2 with epoxides under mild conditions by using a CO2 balloon (1 atm) to produce cyclic carbonates up to 95% yields.

Recent developments in organocatalysed transformations of epoxides and carbon dioxide into cyclic carbonates

“…More recently, Endo et al demonstrated that guanidinium iodide catalysts 32 were catalysts for the synthesis of cyclic carbonates under mild reaction conditions (1 bar carbon dioxide, 25 o C, 24 h, 5 mol% catalyst). 81 In 2019, Wang et al prepared ten achiral phase-transfer catalysts and showed that compound 33 with a quaternary ammonium centre, a urea group as a hydrogen bond donor and a 3,5-bis-trifluoromethylphenyl substituent was the most active catalyst for cyclic carbonate synthesis at 1 bar of carbon dioxide and 80 o C for 24 h. 82 Many terminal epoxides were converted into cyclic carbonates in 65-91% yields. When enantiomerically pure epoxides were used, cyclic carbonates were obtained with 67-99% enantiomeric excess.…”

Recent Advances on Metal‐Organic Frameworks in the Conversion of Carbon Dioxide

“…[ 45,46 ] One of the most important ways to synthesize cyclic carbonate is cycloaddition of CO 2 and epoxide, in which these raw materials are low in price and high in atomic utilization, in accordance with the concept of green chemistry. [ 47‐50 ] The CO 2 cycloaddition reaction is generally considered to be activated by acid sites or acid‐base synergistic sites. [ 51,52 ] Here we classify these catalytic reactions according to the types of MOF acidic sites.…”

Environmentally Benign Synthesis of Cyclic Carbonates from Epoxides and Carbon Dioxide Using Binary and Bifunctional Catalysts

“…independently reported the use of related-bifunctional tetraalkylammonium halide catalysts bearing a thiourea or urea moiety for the synthesis of cyclic carbonate 1a under atmospheric CO 2 pressure. 13,14 Scheme 10. Other bifunctional quaternary onium salt catalysts…”