227016-54-8Relevant academic research and scientific papers
Lipase-catalyzed enantioselective acylation in a halogen free ionic liquid solvent system
Itoh, Toshiyuki,Ouchi, Nozomi,Hayase, Shuichi,Nishimura, Yoshihito
, p. 654 - 655 (2003)
Lipase-catalyzed enantioselective transesterification was demonstrated using several types of imidazolium alkyl sulfate as a reaction medium. The desired optically pure acetate was successfully obtained under the conditions used, although reaction rate was inferior to that in imidazolium tetrafluoroborate.
Ligand-controlled regiodivergent Ni-catalyzed reductive carboxylation of allyl esters with CO2
Moragas, Toni,Cornella, Josep,Martin, Ruben
supporting information, p. 17702 - 17705 (2015/02/19)
A novel Ni-catalyzed regiodivergent reductive carboxylation of allyl esters with CO2 has been developed. This mild, user-friendly, and operationally simple method is characterized by an exquisite selectivity profile that is dictated by the ligand backbone.
Palladacyclic imidazoline-naphthalene complexes: Synthesis and catalytic performance in Pd(II)-catalyzed enantioselective reactions of allylic trichloroacetimidates
Cannon, Jeffrey S.,Frederich, James H.,Overman, Larry E.
supporting information; experimental part, p. 1939 - 1951 (2012/04/23)
A new family of air- and moisture-stable enantiopure C,N-palladacycles (PIN-acac complexes) were prepared in good overall yield in three steps from 2-iodo-1-naphthoic acid and enantiopure β-amino alcohols. Three of these PIN complexes were characterized by single-crystal X-ray analysis. As anticipated, the naphthalene and imidazoline rings of PIN-acac complexes 18a and 18b were canted significantly from planarity and projected the imidazoline substituents R1 and R2 on opposite faces of the palladium square plane. Fifteen PIN complexes were evaluated as catalysts for the rearrangement of prochiral (E)-allylic trichloroacetimidate 19 (eq 2) and the SN2′ allylic substitution of acetic acid with prochiral (Z)-allylic trichloroacetimidate 23. Although these complexes were kinetically poor catalysts for the Overman rearrangement, they were good catalysts for the allylic substitution reaction, providing branched allylic esters in high yield. However, enantioselectivities were low to moderate and significantly less than that realized with palladacyclic complexes of the COP family. Computational studies support an anti-acetoxypalladation/syn-deoxypalladation mechanism analogous to that observed with COP catalysts. The computational study further suggests that optimizing steric influence in the vicinity of the carbon ligand of a chiral C,N-palladacycle, rather than near the nitrogen heterocycle, is the direction to pursue in future development of improved enantioselective catalysts of this motif.
Kinetic resolution of allylic alcohols via stereoselective acylation catalyzed by lipase PS-30
Chen, Peiran,Xiang, Peng
experimental part, p. 5758 - 5760 (2011/12/03)
By using lipase PS-30 as catalyst, the kinetic resolution of a series of racemic allylic alcohols has been achieved via stereoselective acylation. The value of kinetic enantiomeric ratio (E) reached up to 968. Substituent effect is briefly discussed.
Mechanism of the cobalt oxazoline palladacycle (COP)-catalyzed asymmetric synthesis of allylic esters
Cannon, Jeffrey S.,Kirsch, Stefan F.,Overman, Larry E.,Sneddon, Helen F.
supporting information; experimental part, p. 15192 - 15203 (2011/01/06)
The catalytic enantioselective SN2′ displacement of (Z)-allylic trichloroacetimidates catalyzed by the palladium(II) complex [COP-OAc]2 is a broadly useful method for the asymmetric synthesis of chiral branched allylic esters. A vari
A rational design of phosphonium salt type ionic liquids for ionic liquid coated-lipase catalyzed reaction
Abe, Yoshikazu,Yoshiyama, Kazuhide,Yagi, Yusuke,Hayase, Shuichi,Kawatsura, Motoi,Itoh, Toshiyuki
, p. 1976 - 1980 (2011/02/23)
A rational design of phosphonium ionic liquid for ionic liquid coated-lipase (IL1-PS)-catalyzed reaction has been investigated, and very rapid transesterification of secondary alcohols accomplished when IL1-PS was used as catalyst in 2-methoxyethoxymethyl(tri-n-butyl)phosphonium bis(trifluoromethanesulfonyl)amide ([P444MEM][NTf2]) as solvent while perfect enantioselectivity was maintaining. Increased K cat value was suggested to be the most important factor in IL1-PS working the best in [P444MEM][NTf2] solvent. The Royal Society of Chemistry 2010.
Increased enantioselectivity and remarkable acceleration of lipase-catalyzed transesterification by using an imidazolium PEG-Alkyl sulfate ionic liquid
Itoh, Toshiyuki,Matsushita, Yuichi,Abe, Yoshikazu,Han, Shi-Hui,Wada, Shohei,Hayase, Shuichi,Kawatsura, Motoi,Takai, Shigeomi,Morimoto, Minoru,Hirose, Yoshihiko
, p. 9228 - 9237 (2007/10/03)
Several types of imidazolium salt ionic liquids were prepared derived from poly(oxyethylene)alkyl sulfate and used as an additive or coating material for lipase-catalyzed transesterification in an organic solvent. A remarkably increased enantioselectivity was obtained when the salt was added at 3-10 mol % versus substrate in the Burkholderia cepacia lipase (lipase PS-C)-catalyzed transesterification of 1-phe nylethanol by using vinyl acetate in diisopropyl ether or a hexane solvent system. In particular, a remarkable acceleration was accomplished by the ionic liquid coating with lipase PS in an iPr2O solvent system while maintaining excellent enantioselectivity; it reached approximately 500- to 1000-fold acceleration for some substrates with excellent enantioselectivity. A similar acceleration was also observed for IL1-coated Candida rugosa lipase. MALDITOF mass spectrometry experiments of the ionic-liquid-coated lipase PS suggest that ionic liquid binds with lipase protein.
IONIC LIQUID AND METHOD FOR PRODUCING THE SAME
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Page/Page column 8; 10, (2008/06/13)
PROBLEM TO BE SOLVED: To provide an ionic liquid that can widely be used as a material for a variety of electric devices and a solvent for a variety of reactions wherein this ionic liquid has the hydrophobic properties to cause the phase separation with water and provide a method for producing the same. SOLUTION: The ionic liquid includes at least one anion selected from the group consisting of fluoroalkylsulfate anion, fluorocycloalkylsulfate anion and fluorobenzylsulfate anion and is hydrophobic to water and separable from water. In this ionic liquid, the concentration of halogenated compound ion can be reduced less than 70 ppm. COPYRIGHT: (C)2006,JPOandNCIPI
Lipase-catalyzed enantioselective acylation in the ionic liquid solvent system: Reaction of enzyme anchored to the solvent
Itoh, Toshiyuki,Akasaki, Eri,Kudo, Kazutoshi,Shirakami, Shohei
, p. 262 - 263 (2007/10/03)
The lipase-catalyzed enantioselective acylation of allylic alcohols in an ionic liquid solvent was demonstrated; the reaction was significantly dependent on the counter anion of the imidazolium salt and good results were obtained when the reaction was car
