22147-28-0Relevant articles and documents
An Aminopyridinium Ionic Liquid: A Simple and Effective Bifunctional Organocatalyst for Carbonate Synthesis from Carbon Dioxide and Epoxides
Al-Harrasi, Ahmed,Ebrahimi, Amirhossein,Khosravi, Hormoz,Rezazadeh, Mostafa,Rostami, Ali
, p. 1587 - 1595 (2020/08/05)
An aminopyridinium ionic liquid is presented as a green, tunable, and active metal-free one-component catalytic system for the atom-efficient transformation of oxiranes and CO2 to cyclic carbonates. Inclusion of a positively charged moiety into aminopyridines, through a simple single-step synthesis, provides a one-component ionic liquid catalytic system with superior activity; effective in ring opening of epoxide, CO2 inclusion, and stabilization of oxoanionic intermediates. An efficiency assessment of a variety of positively charged aminopyridines was pursued, and the impact of temperature, catalyst loading, and the kind of nucleophile on the catalytic performance was also investigated. Under solvent-free conditions, this bifunctional organocatalytic system was used for the preparation of 18 examples of cyclic carbonates from a broad range of alkyl- and aryl-substituted oxiranes and CO2, where up to 98 percent yield and high selectivity were achieved. DFT calculations validated a mechanism in which nucleophilic ring-opening and CO2 inclusion occur simultaneously towards cyclic carbonate formation.
Bifunctional phase-transfer catalysts for fixation of CO2 with epoxides under ambient pressure
Li, Yue-Dan,Cui, Dong-Xiao,Zhu, Jun-Chao,Huang, Ping,Tian, Zhuang,Jia, Yan-Yan,Wang, Ping-An
supporting information, p. 5231 - 5237 (2019/10/11)
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 commercially available epoxides under mild conditions by using a CO2 balloon (1 atm). In the presence of 2.5 mol% of achiral bifunctional phase-transfer catalysts, cyclic carbonates were obtained in good to excellent yields (up to 95%). Additionally, optical carbonates and epoxides were obtained through the kinetic resolution of rac-epoxides by 1 mol% of chiral bifunctional phase-transfer catalysts with low enantioselectivities. These catalysts featured a simple synthetic route, good modularity and high efficiency.
CO2 Adducts of Phosphorus Ylides: Highly Active Organocatalysts for Carbon Dioxide Transformation
Zhou, Hui,Wang, Guo-Xu,Zhang, Wen-Zhen,Lu, Xiao-Bing
, p. 6773 - 6779 (2015/11/18)
A series of phosphorus ylide (P-ylide) CO2 adducts were synthesized and first used as organocatalysts for CO2 transformation. Detailed studies on the cycloaddition reaction of CO2 with terminal epoxides show that P-ylide CO2 adducts are efficient metal-free and halogen-free organocatalysts to mediate this reaction under ambient conditions (25 °C, 1 atm of CO2). More importantly, the reactions proceeded with a broad scope, high efficiency, and good functional group tolerance and the corresponding cyclic carbonate products were obtained in good to excellent yields (46-99%). Meanwhile, the kinetic study by in situ FTIR methods suggested an intermolecular cooperation effect for effectively accelerating the ring opening of terminal epoxides. Furthermore, from an investigation of the catalytic diversity of P-ylide CO2 adducts, CO2 also could be converted to functionalized cyclic α-alkylidene carbonates, oxazolidinone, and N-methylated and N-formylated amines by organocatalytic reactions.
