scholarly journals Proline Based Chiral Ionic Liquids for Enantioselective Michael Reaction

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Kaoru Nobuoka ◽  
Satoshi Kitaoka ◽  
Tsutomu Kojima ◽  
Yuuki Kawano ◽  
Kazuya Hirano ◽  
...  

Chiral ionic liquids, starting from (S)-proline, have been prepared and evaluated the ability of a chiral catalyst. In Michael reaction of trans-β-nitrostyrene and cyclohexanone, all the reactions were carried out under homogeneous conditions without any solvent except for excess cyclohexanone. The chiral ionic liquid catalyst with the positive charge delocalized bulky pyrrolidinium cation shows excellent yields (up to 92%), diastereoselectivities (syn/anti = 96/4), and enantioselectivities (up to 95% ee) and could be reused at least three times without any loss of its catalytic activity. Such results demonstrated a promising new approach for green and economic chiral synthesis by using the chiral ionic liquids as a chiral catalyst and a chiral medium.

2015 ◽  
Vol 68 (10) ◽  
pp. 1513 ◽  
Author(s):  
Miaona Feng ◽  
Guoying Zhao ◽  
Hongling Gao ◽  
Suojiang Zhang

Novel tetracarboxyl-functionalized 2,2′-biimidazolium-based ionic liquids (ILs) with different anions were synthesized in two steps from readily available and sustainable starting materials including ammonium acetate, glyoxal, and halogenated propionic acid. The functionalized IL exhibited higher catalytic activity towards the cycloaddition of CO2 to terminal epoxides. With propylene oxide as a substrate, the optimum yield of propylene carbonate reached 82.7 % at an initial CO2 pressure of 2.0 MPa for 4 h at 140°C. Moreover, the functionalized IL catalyst displayed a high stability and can be reused for at least five cycles without obvious loss of catalytic activity. The results provide a simple and economical way to synthesize multi-functionalized imidazolium-based ILs with versatile potential applications.


RSC Advances ◽  
2018 ◽  
Vol 8 (47) ◽  
pp. 26922-26927 ◽  
Author(s):  
Magdalena Jankowska-Wajda ◽  
Izabela Dąbek ◽  
Ryszard Fiedorow ◽  
Hieronim Maciejewski

Rhodium and platinum complexes were immobilized in morpholinium ionic liquids, the effect of which on the catalytic activity was determined.


Catalysts ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 814
Author(s):  
Katia Bacha ◽  
Kawther Aguibi ◽  
Jean-Pierre Mbakidi ◽  
Sandrine Bouquillon

We developed a synthesis of chiral ionic liquids from proline and one of its derivatives. Nine chiral ionic liquids were synthesized with yields from 78% to 95%. These synthesized ionic liquids played two roles in Michael reactions, as solvents, and as basic catalysts, where the ionic phase could also be reused at least five times without loss of activity. The yields up to 99% were improved by increasing the amount of dimethylmalonate from 1.2 equivalents to 3 or 4 equivalents. Furthermore, the reaction time could be reduced from 24 h to 45 min through microwaves activation.


2012 ◽  
Vol 48 (26) ◽  
pp. 3185 ◽  
Author(s):  
Viacheslav Zgonnik ◽  
Chantal Zedde ◽  
Yves Génisson ◽  
Marie-Rose Mazières ◽  
Jean-Christophe Plaquevent

2014 ◽  
Vol 16 (7) ◽  
pp. 3463-3471 ◽  
Author(s):  
Karolina Matuszek ◽  
Anna Chrobok ◽  
Fergal Coleman ◽  
Kenneth R. Seddon ◽  
Małgorzata Swadźba-Kwaśny

The speciation of a family of inexpensive, easily prepared protonic ionic liquids, their physico-chemical properties and their performance as catalysts in the model esterification reaction have been correlated.


2016 ◽  
Vol 18 (48) ◽  
pp. 32723-32734 ◽  
Author(s):  
Kaixin Li ◽  
Yibo Yan ◽  
Jun Zhao ◽  
Junxi Lei ◽  
Xinli Jia ◽  
...  

The intra- and inter-hydrogen bonding networks that govern the catalytic activity of Brønsted acidic ionic liquids were identified.


Synfacts ◽  
2006 ◽  
Vol 2006 (6) ◽  
pp. 0611-0611
Author(s):  
S. Luo ◽  
J.-P. Cheng ◽  
X. Mi ◽  
L. Zhang ◽  
S. Liu ◽  
...  

ChemInform ◽  
2012 ◽  
Vol 43 (30) ◽  
pp. no-no
Author(s):  
Viacheslav Zgonnik ◽  
Chantal Zedde ◽  
Yves Genisson ◽  
Marie-Rose Mazieres ◽  
Jean-Christophe Plaquevent

Synthesis ◽  
2018 ◽  
Vol 50 (18) ◽  
pp. 3708-3714 ◽  
Author(s):  
Da-Zhen Xu ◽  
Cheng-Bin Li ◽  
Yu-Wei Li

An efficient, economical, and green strategy for the construction of biologically relevant 2-amino-4H-chromene scaffolds via a tandem Knoevenagel–Pinner cyclization–Michael reaction has been successfully developed. In the presence of DABCO-based ionic liquids, two different 2-amino-4H-chromene derivatives, 2-amino-4-(indol-3-yl)-4H-chromenes and 2-amino-4-(pyrazol-4-yl)-4H-chromenes, were prepared in good to excellent yields (81–97%) within short reaction times under mild conditions. All the products are purified by simple crystallization. The catalyst could be recycled for at least five times.


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