- Demonstration of chemisorption of carbon dioxide in 1,3-dialkylimidazolium acetate ionic liquids
-
Real chemistry: Spectroscopic and crystallographic analyses confirm the chemical reaction of CO2 with carbene present in 1,3- dialkylimidazolium acetate ionic liquids and the supporting role of the acetate ion. When CO2 was bubbled through [C2mim][OAc], formation of the corresponding imidazolium carboxylate, [C2mim +-COO-], could be observed. Copyright
- Gurau, Gabriela,Rodriguez, Hector,Kelley, Steven P.,Janiczek, Peter,Kalb, Roland S.,Rogers, Robin D.
-
-
Read Online
- Metal-free imidazolium hydrogen carbonate ionic liquids as bifunctional catalysts for the one-pot synthesis of cyclic carbonates from olefins and CO2
-
A direct route for the synthesis of cyclic carbonates from olefins and CO2 has been achieved by using imidazolium hydrogen carbonate ionic liquids ([CnCmIm][HCO3]) as bifunctional catalysts in the absence of a solvent. [CnCmIm][HCO3] can convert into a carbene-CO2 adduct spontaneously. The HCO3- anion and carbene-CO2 can serve as catalysts for olefin epoxidation and CO2 cycloaddition, respectively, which obviously simplifies the synthesis of cyclic carbonates. The reaction proceeds quite well under mild conditions. This cheap and simple method can be applied to various olefins with good to excellent yields of cyclic carbonates. The catalyst can be easily recycled at least four times without significantly losing its catalytic activity.
- Liu, Jia,Yang, Guoqiang,Liu, Ying,Wu, Dongsheng,Hu, Xingbang,Zhang, Zhibing
-
supporting information
p. 3834 - 3838
(2019/07/31)
-
- Ascorbic acid based ionic liquids: Recyclable and efficient catalytic systems for the huisgen cycloaddition
-
A new method for the Huisgen cycloaddition using an ascorbic acid based ionic liquid and a copper catalyst in an ionic liquid, under microwave irradiation, is described. The reaction times are short and a simple procedure for separation of the products is
- Koguchi, Shinichi,Nakamura, Kaori
-
p. 2305 - 2309
(2013/11/06)
-
- Imidazolium hydrogen carbonates versus imidazolium carboxylates as organic precatalysts for N-heterocyclic carbene catalyzed reactions
-
Imidazolium-2-carboxylates (NHC-CO2 adducts, 3) and (benz)imidazolium hydrogen carbonates ([NHC(H)][HCO3], 4) were independently employed as organic precatalysts for various molecular N-heterocyclic carbene (NHC) catalyzed reactions. NHC-CO2 adducts were obtained by carboxylation in THF of related free NHCs (2), while the synthesis of [NHC(H)][HCO3] precursors was directly achieved by anion metathesis of imidazolium halides (1) using potassium hydrogen carbonate (KHCO3) in methanolic solution, without the need for the prior preparation of free carbenes. Thermogravimetric analysis (TGA) and TGA coupled with mass spectrometry (TGA-MS) of most [NHC(H)][HCO3] precursors 4 showed a degradation profile in stages, with either a concomitant or a stepwise release of H2O and CO2, between 108 and 280 °C, depending on the nature of the azolium and substituents. In solution, NHC generation from both [NHC(H)][HCO3] salts and NHC-CO2 adducts could be achieved at room temperature, most likely by a simple solvation effect. Both types of precursors proved efficient for organocatalyzed molecular reactions, including cyanosilylation, benzoin condensation, and transesterification reactions. The catalytic efficiencies of NHC-CO2 adducts 3 were found to be approximately 3 times higher than those of their [NHC(H)][HCO3] counterparts 4.
- Fevre, Mareva,Coupillaud, Paul,Miqueu, Karinne,Sotiropoulos, Jean-Marc,Vignolle, Joan,Taton, Daniel
-
p. 10135 - 10144
(2013/01/15)
-
- Ionic liquids as benign catalysts for the carbonylation of amines to formamides
-
1-Butyl-3-methylimidazolium hydrogen carbonate ([BMIm][HCO3]), prepared from the reaction of [BMIm]Cl with K2CO3 in methanol, exhibits high activity for the carbonylation of amines to produce formamides. Computational calculation results on the carbonylation reaction of methylamine implies that such high activity of [BMIm][HCO3] could be ascribed to the bi-functional actions of [HCO3]- as a hydrogen atom acceptor and a donor.
- Choi, Young-Seop,Shim, Yu Na,Lee, Jeesun,Yoon, Jung Hee,Hong, Chang Seop,Cheong, Minserk,Kim, Hoon Sik,Jang, Ho Gyeom,Lee, Je Seung
-
experimental part
p. 87 - 92
(2012/02/05)
-
- A solventless route to 1-ethyl-3-methylimidazolium fluoride hydrofluoride, [C2mim][F]·xHF
-
(Chemical Equation Presented) The ionic liquid 1-ethyl-3-methylimidazolium fluoride hydrofluoride, [C2mim][F]·xHF, has been synthesized through a new, solventless route that excludes halogen metathesis. The byproducts are salts, alcohols, and carbon dioxide.
- Rijksen, Christiaan,Rogers, Robin D.
-
p. 5582 - 5584
(2008/12/20)
-