- Enhanced activity and modified substrate-favoritism of Burkholderia cepacia lipase by the treatment with a pyridinium alkyl-PEG sulfate ionic liquid
-
Three types of pyridinium salts, i.e., 1-ethylpyridin-1-ium cetyl-PEG10 sulfate (PYET), 1-butylpyridin-1-ium cetyl-PEG10 sulfate (PYBU), and 1-(3-methoxypropyl)pyridin-1-ium cetyl-PEG10 sulfate (PYMP), have been prepared and evaluated for their activation property of Burkholderia cepacia lipase by comparison to the control IL-coated enzymes, 1-butyl-2,3-dimethylimidazolium cetyl-PEG10 sulfate-coated lipase PS (IL1-PS). Among the tested pyridinium salt-coated lipases, the PYET-coated lipase PS (PYET-PS) exhibited the best results; the transesterification of 1-(pyridin-2-yl)ethanol, 1-(pyridin-3-yl)ethanol, 1-(pyridin-4-yl)ethanol, or 4-phenylbut-3-en-2-ol proceeded faster than those of the IL1-PS-catalyzed reaction while maintaining an excellent enantioselectivity (E > 200). This improved efficiency was found to be dependent on the increased Kcat value.
- Kadotani, Shiho,Nokami, Toshiki,Itoh, Toshiyuki
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p. 441 - 447
(2019/01/04)
-
- Pickering Emulsion-Derived Liquid-Solid Hybrid Catalyst for Bridging Homogeneous and Heterogeneous Catalysis
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We describe a novel method to prepare a liquid-solid hybrid catalyst via interfacial growth of a porous silica crust around Pickering emulsion droplets, which allowed us to overcome the current limitations of both homogeneous and heterogeneous catalysts. The inner micron-scaled liquid (for example, ionic liquids) pool of the resultant catalyst can host free homogeneous molecular catalysts or enzymes to create a true homogeneous catalysis environment. The porous silica crust of the hybrid catalyst has excellent stability, which makes it amenable to packing directly in fixed-bed reactors for continuous flow catalysis. As a proof of concept, the enzymatic kinetic resolution of racemic alcohols, CrIII(salen) complex-catalyzed asymmetric ring opening of epoxides and Pd-catalyzed Tsuji-Trost allylic substitution reactions were used to verify the generality and versatility of our strategy for bridging homogeneous and heterogeneous catalysis. The hybrid catalyst-based continuous flow system exhibited a 1.6a16-fold enhancement in activity relative to homogeneous counterparts even over 1500 h, and the afforded enantioselectivities were completely equal to those obtained in the homogeneous counterpart systems. Interestingly, the catalytic efficiency can be tuned through rational engineering of the porous crust and the dimensions of the liquid pool, resulting in features of an innovatively designed catalyst. This contribution provides a new method to design efficient catalysts that can bridge the conceptual and technical gaps between homogeneous and heterogeneous catalysis.
- Zhang, Xiaoming,Hou, Yiting,Ettelaie, Rammile,Guan, Ruqun,Zhang, Ming,Zhang, Yabin,Yang, Hengquan
-
supporting information
p. 5220 - 5230
(2019/03/11)
-
- Identification of an Esterase Isolated Using Metagenomic Technology which Displays an Unusual Substrate Scope and its Characterisation as an Enantioselective Biocatalyst
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Evaluation of an esterase annotated as 26D isolated from a marine metagenomic library is described. Esterase 26D was found to have a unique substrate scope, including synthetic transformations which could not be readily effected in a synthetically useful manner using commercially available enzymes. Esterase 26D was more selective towards substrates which had larger, more sterically demanding substituents (i. e. iso-propyl or tert-butyl groups) on the β-carbon, which is in contrast to previously tested commercially available enzymes which displayed a preference for substrates with sterically less demanding substituents (e.g. methyl group) at the β-carbon. (Figure presented.).
- Gavin, Declan P.,Murphy, Edel J.,Foley, Aoife M.,Castilla, Ignacio Abreu,Reen, F. Jerry,Woods, David F.,Collins, Stuart G.,O'Gara, Fergal,Maguire, Anita R.
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p. 2466 - 2474
(2019/03/11)
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- Remarkably improved stability and enhanced activity of a: Burkholderia cepacia lipase by coating with a triazolium alkyl-PEG sulfate ionic liquid
-
Three types of triazolium cetyl-PEG10 sulfate ionic liquid were synthesized and their activation of Burkholderia cepacia lipase was investigated; both the reaction rate and enantioselectivity depended on the cationic part of the coating ILs and 1-butyl-3-methyl-1,2,3-triazolium cetyl-PEG10 sulfate (Tz1)-coated lipase PS, which is especially suitable for the transesterification of 1-(pyridin-2-yl)ethanol, 1-(pyridin-3-yl)ethanol, and 1-(pyridin-4-yl)ethanol, among 12 types of tested secondary alcohol. The most important result was obtained when these enzymes were stored in an IL ([N221MEM][Tf2N]) solvent: Tz1-PS showed an amazing stability and it exhibited an excellent activity after 2 years when the enzyme was stored in [N221MEM][Tf2N].
- Nishihara,Shiomi,Kadotani,Nokami,Itoh
-
supporting information
p. 5250 - 5256
(2017/11/09)
-
- Synthetically useful variants of industrial lipases from: Burkholderia cepacia and Pseudomonas fluorescens
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Industrial enzymes lipase PS (LPS) and lipase AK (LAK), which originate from Burkholderia cepacia and Pseudomonas fluorescens, respectively, are synthetically useful biocatalysts. To strengthen their catalytic performances, we introduced two mutations into hot spots of the active sites (residues 287 and 290). The LPS-L287F/I290A double mutant showed high catalytic activity and enantioselectivity for poor substrates for which the wild-type enzyme showed very low activity. The LAK-V287F/I290A double mutant was also an excellent biocatalyst with expanded substrate scope, which was comparable to the LPS-L287F/I290A double mutant. Thermodynamic parameters were determined to address the origin of the high enantioselectivity of the double mutant. The ΔΔH? term, but not the ΔΔS? term, was predominant, which suggests that the enantioselectivity is driven by a differential energy associated with intermolecular interactions around Phe287 and Ala290. A remarkable solvent effect was observed, giving a bell-shaped profile between the E values and the log&P or ? values of solvents with the highest E value in i-Pr2O. This suggests that an organic solvent with appropriate hydrophobicity and polarity provides the double mutant with some flexibility that is essential for excellent catalytic performance.
- Yoshida, Kazunori,Ono, Masakazu,Yamamoto, Takahiro,Utsumi, Takashi,Koikeda, Satoshi,Ema, Tadashi
-
supporting information
p. 8713 - 8719
(2017/11/03)
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- Chemoenzymatic synthesis of rasagiline mesylate using lipases
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A straightforward chemoenzymatic synthesis of rasagiline mesylate has been developed. The key steps for the introduction of chirality involved kinetic enzymatic resolution with lipases via acetylation of racindanol and an inversion configuration Mitsunobu reaction of the produced (S)-indanol. Immobilized lipase from Thermomyces lanuginosus proved to be a robust biocatalyst in the kinetic resolution, leading to (S)-indanol with high selectivity (e.e. > 99%, E > 200) in just 15 min, at 35°C, in hexane, being reused for ten-times without significant loss of the activity and selectivity.
- De Mattos, Marcos Carlos,De Fonseca, Thiago Sousa,Da Silva, Marcos Reinaldo,De Oliveira, Maria Da Concei??o Ferreira,De Lemos, Telma Leda Gomes,De Marques, Ricardo Araújo
-
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- Kinetic resolution of secondary alcohols with Burkholderia cepacia lipase immobilized on a biodegradable ternary blend polymer matrix as a highly efficient and heterogeneous recyclable biocatalyst
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The present work reports a highly efficient and biocatalytic heterogeneous protocol for kinetic resolution (KR) of racemic secondary alcohols with vinyl acetate as an acyl donor, using the biocatalyst Burkholderia cepacia lipase (BCL) immobilized on a biodegradable ternary blend support through polylactic acid (PLA)/polyvinyl alcohol (PVA)/chitosan (CHI); (PLA/PVA/CHI-BCL). The KR reaction with various substituted aromatic, heterocyclic racemic secondary alcohols gave enantiomerically pure alcohol and its enantioenriched acetate derivatives with high conversion (45-50%) and excellent enantiomeric excess (up to 99% ee) at optimized reaction conditions. The reaction works under mild conditions using simple and inexpensive starting materials such as racemic alcohols, vinyl acetate, and immobilized biocatalyst. The given protocol provides excellent recyclability with good yield and enantiomeric excess values up to the studied range of five cycles. The resultant products were characterized with the help of different analytical techniques such as 1H and 13C-NMR, chiral HPLC column, polarimeter, IR and GC-MS.
- More, Ganesh V.,Badgujar, Kirtikumar C.,Bhanage, Bhalchandra M.
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p. 4592 - 4598
(2015/02/19)
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- CAL-B-Catalyzed Enantioselective Deacetylation of Some Benzylic Acetate Derivatives Via Alcoholysis in Non-aqueous Media
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Enantioselective deacetylation of a set of benzylic acetates via alcoholysis catalyzed by Lipase B from Candida antarctica (CAL-B), under mild conditions is described. A systematic study allows to determine the appropriate combination nucleophile/organic solvent and also to explain the influence of these parameters on the enzymatic catalytic reaction. In all cases, (R)-alcohols are obtained with high ee (up to >99 %) at conversion 36 % 500. The enzymatic reactivity is influenced by the hydrophobicity of solvent and the structure/nature of the nucleophile. Furthermore, CAL-B allows enantio-complementary between transesterifications in non-aqueous media: alcoholysis and acetylation.
- Zadi, Amna,Merabet-Khelassi, Mounia,Aribi-Zouioueche, Louisa
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p. 1054 - 1061
(2015/02/05)
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- Separation of enantiopure m-substituted 1-phenylethanols in high space-time yield using Bacillus subtilis esterase
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A recombinant Bacillus subtilis esterase (BsE) expressed in E. coli was found to exhibit excellent enantioselectivity (E was always greater than 100) towards m-substituted 1-phenylethanol acetates in the enantioselective hydrolysis reaction. An explanation for the high enantioselectivity observed towards these substrates was provided by molecular modeling. Moreover, the BsE also showed strong tolerance towards a high concentration of m-substituted 1-phenylethanol acetates (up to 1 M). Based on these excellent catalytic properties of BsE, a kind of m-substituted 1-phenylethanols, (R)-1-(3-chlorophenyl)ethanol, was efficiently synthesized in space-time yield of 920 g per L per day and 97% ee, indicating that the BsE was considered as a potentially ideal and promising biocatalyst for large-scale production of optically active m-substituted 1-phenylethanols. The Royal Society of Chemistry 2013.
- Zheng, Gao-Wei,Liu, Xu-Yun,Zhang, Zhi-Jun,Tian, Ping,Lin, Guo-Qiang,Xu, Jian-He
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p. 20446 - 20449
(2013/11/06)
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- A green route to enantioenriched (S)-arylalkyl carbinols by deracemization via combined lipase alkaline-hydrolysis/Mitsunobu esterification
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Herein we report results of the chemoenzymatic deracemization of a range of secondary benzylic acetates 1a-9a via a sequence of hydrolysis with CAL-B lipase in non-conventional media, combined with esterification of the recovered alcohol according to the Mitsunobu protocol following an enzymatic kinetic resolution (KR). The KR of racemic acetates 1a-9a via an enzymatic hydrolysis, with CAL-B lipase and Na2CO3, in non-aqueous media was optimized and gave high selectivities (E ? 200) at good conversions (C >49%) for all of the substrates studied. This method competes well with the traditional one performed in a phosphate buffer solution. The deracemization using Mitsunobu inversion gave the (S)-acetates in moderate to excellent enantiomeric excess 75% ee 99%, in acceptable isolated yields 70% yield 89%, and with some variations according to the acetate structure.
- Houiene, Zahia,Merabet-Khelassi, Mounia,Bouzemi, Nassima,Riant, Olivier,Aribi-Zouioueche, Louisa
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p. 290 - 296
(2013/04/23)
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- Development of an improved immobilized CAL-B for the enzymatic resolution of a key intermediate to odanacatib
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An immobilized form of Candida antarctica lipase B (CAL-B) has been developed with enhanced stability and activity compared to commercially available preparations. The immobilized CAL-B is more active, and 15 times more stable than the previously used preparation. This permits a continuous dynamic kinetic resolution process that is significantly less expensive than the original batch process, and with a 3-fold reduction in the process E-factor.
- Truppo, Matthew D.,Hughes, Gregory
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scheme or table
p. 1033 - 1035
(2012/01/03)
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- Racemization of secondary alcohols catalyzed by ruthenium: Application to chemoenzymatic dynamic resolution
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In this paper, we have shown that the [RuCl2(p-cymene)] 2 complex associated with simple hemisalen ligands is able to racemize (S)-1-phenylethanol. The influence on the racemization process of the ligand's structure as well as the nature of a co-catalyst have been evaluated and optimized. This [RuCl2(p-cymene)]2/Ligand/TEMPO racemization system was then associated with the Candida Antarctica B lipase in order to carry out dynamic kinetic resolution experiments on rac-phenylethanol. This led us to identify the best conditions for effective DKR, which was then applied to various secondary benzylic and aliphatic alcohols. It was thus possible to obtain (R)-1-cyclohexylethyl acetate from rac-1-cyclohexylethanol in quantitative conversion and with high enantioselectivity (98%).
- Merabet-Khelassi, Mounia,Vriamont, Nicolas,Aribi-Zouioueche, Louisa,Riant, Olivier
-
experimental part
p. 1790 - 1796
(2012/01/03)
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- Chemoenzymatic deracemization of chiral secondary alcohols: Process optimization for production of (R)-1-indanol and (R)-1-phenylethanol
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A process for preparing chiral secondary alcohols by chemoenzymatic deraeemization was optimized. First, the transesterification process of 1-indanol and 1-phenylethanol with vinyl acetate as the acyl donor was optimized using lipase Novozym 435 as biocatalyst The effects of acyl donors, substrate concentration, solvent type, and enzyme amount on activity and enantioselectivity of the said transesteriflcation were investigated. Second,on the basis of the optimized conditions, an efficient biocatalytic resolution system was established with high selectivity, where volumetric productivity of the reaction against (R)-l-indanol and (R)-lphenylethanol reached 529 and 198 g L-1 d-1, respectively, during reuse of the enzyme in repeated-batch transesteriflcation reactions. After 10 batches of the reaction, the enzyme still remained stable. Finally, (R)- 1-indanol and (R)-l-phenylethanol were obtained in 95% and 97% ee and in 67% and 71% isolated yields from the corresponding resolution mixture, through an in situ Mitsunobu inversion of the unreaeted alcohols followed by chemical hydrolysis of (R)-acetates.
- Ou, Ling,Xu, Yi,Ludwig, Daniel,Pan, Jiang,Xu, Jian He
-
p. 192 - 195
(2013/01/03)
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- Combined lipase-catalyzed resolution/Mitsunobu esterification for the production of enantiomerically enriched arylalkyl carbinols
-
Several arylalkyl carbinols [1-indanol, 1-tetralol, 1-phenylethanol, 1-(1-naphthyl)ethanol, 1-(2-naphthyl)ethanol, 1-(4-methoxyphenyl)ethanol, 1-acenaphthenol] were deracemized through sequential combinations of lipase-catalyzed resolution and Mitsunobu inversion. The corresponding (R)-acetates were obtained in 72-83% yield and 89-99% ee.
- Bouzemi, Nassima,Aribi-Zouioueche, Louisa,Fiaud, Jean-Claude
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p. 797 - 800
(2007/10/03)
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- Air-stable racemization catalyst for dynamic kinetic resolution of secondary alcohols at room temperature
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(Chemical Equation Presented) A novel racemization catalyst was synthesized for the dynamic kinetic resolution (DKR) of alcohols with a lipase at room temperature in the air. Furthermore, a polymer-supported derivative was also synthesized and tested as a recyclable catalyst for the aerobic DKR of alcohols.
- Kim, Namdu,Ko, Soo-Byung,Min, Serk Kwon,Kim, Mahn-Joo,Park, Jaiwook
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p. 4523 - 4526
(2007/10/03)
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- On the use of succinic anhydride as acylating agent for practical resolution of aryl-alkyl alcohols through lipase-catalyzed acylation
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A comparison is carried out of the E-values recorded in the lipase-catalyzed resolution of a series of secondary aryl-alkyl alcohols with enol esters versus succinic anhydride. Whereas all the substrates could be resolved by a proper choice of the lipase/enol ester couple with moderate (E=50) to good (E>100) enantioselectivities, only some of them showed satisfactory enantioselectivity (E>50) with the use of succinic acid as acylating agent. Notably, indanol and 1-quinolin-3-yl-ethanol were resolved in a practical way, with E>100 and E>80, respectively.
- Bouzemi, Nassima,Debbeche, Hanane,Aribi-Zouioueche, Louisa,Fiaud, Jean-Claude
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p. 627 - 630
(2007/10/03)
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- Aminocyclopentadienyl Ruthenium Complexes as Racemization Catalysts for Dynamic Kinetic Resolution of Secondary Alcohols at Ambient Temperature
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Aminocyclopentadienyl ruthenium complexes, which can be used as room-temperature racemization catalysts with lipases in the dynamic kinetic resolution (DKR) of secondary alcohols, were synthesized from cyclopenta-2,4-dienimines, Ru3(CO)12, and CHCl 3: [2,3,4,5-Ph4(η5-C 4CNHR)]Ru-(CO)2Cl (4: R = i-Pr; 5: R = n-Pr; 6: R = t-Bu), [2,5-Me2-3,4-Ph2(η5-C 4CNHR)]Ru(CO)2Cl (7: R = i-Pr; 8: R = Ph), and [2,3,4,5-Ph4(η5-C4CNHAr)]Ru(CO) 2Cl (9: Ar =p-NO2C6H4; 10: Ar = p-ClC6H4; 11: Ar = Ph; 12: Ar = p-OMeC6H 4; 13: Ar = p-NMe2C6H4). The tests in the racemization of (S)-4-phenyl-2-butanol showed that 7 is the most active catalyst, although the difference decreased in the DKR. Complex 4 was used in the DKR of various alcohols; at room temperature, not only simple alcohols but also functionalized ones such as allylic alcohols, alkynyl alcohols, diols, hydroxyl esters, and chlorohydrins were successfully transformed to chiral acetates. In mechanistic studies for the catalytic racemization, ruthenium hydride 14 appeared to be a key species. It was the major organometallic species in the racemization of (S)-1-phenylethanol with 4 and potassium tert-butoxide. In a separate experiment, (S)-1-phenylethanol was racemized catalytically by 14 in the presence of acetophenone.
- Choi, Jun Ho,Choi, Yoon Kyung,Kim, Yu Hwan,Park, Eun Sil,Kim, Eun Jung,Kim, Mahn-Joo,Park, Jaiwook
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p. 1972 - 1977
(2007/10/03)
-
- Entrapment of Pseudomonas cepacia lipase with peracetylated β-cyclodextrin in sol-gel: Application to the kinetic resolution of secondary alcohols
-
Co-lyophilized Pseudomonas cepacia lipase with peracetylated β-cyclodextrin was immobilized by the sol-gel process. The gel-entrapped lipase/cyclodextrin was prepared by the hydrolysis of methyltrimethoxysilane (MTMS) in the presence of the co-lyophilized lipase with peracetylated β-cyclodextrin prepared with different weight ratios (enzyme to CD). This type of enzyme preparation was subsequently used in the kinetic resolution of a set of secondary alcohols using isopropenyl acetate as an innocuous acyl donor in toluene as the organic medium. The resulting chiral alcohols (substrate) and the corresponding acetates (product) were baseline separated in one analysis without derivatization using gas chromatography on a new chiral stationary phase (CSP) Chirasil-β-Dex containing an undecamethylene spacer (C11-Chirasil-Dex).
- Ghanem, Ashraf,Schurig, Volker
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p. 2547 - 2555
(2007/10/03)
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- Ligand-Assisted Rate Acceleration in Transacylation by a Yttrium - Salen Complex. Demonstration of a Conceptually New Strategy for Metal-Catalyzed Kinetic Resolution of Alcohols
-
(matrix presented) Yttrium-salen complexes effect transacylation between enolesters and chiral secondary alcohols, resulting in varying degrees of kinetic resolution. Even though the enantioselectivity remains modest (kfast/kslow up to 4.81), these results represent the first demonstration of a conceptually new metal-catalyzed acyl transfer process that results in kinetic resolution. On the basis of the solid-state structure of the catalyst, a novel associative mechanistic pathway is proposed for the reaction.
- Lin, Mei-Huey,RajanBabu
-
p. 1607 - 1610
(2007/10/03)
-
- Highly enantioselective aminoacylase-catalyzed transesterification of secondary alcohols
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The aminoacylase (N-acyl-L-amino acid amidohydrolase; E.C. 3.5.1.14) from Aspergillus melleus, a readily available inexpensive enzyme, catalyzes the transesterification of a wide range of chiral secondary arylalkanols with essentially absolute stereoselectivity (E> 500). Moreover, the productivities obtained with 1-phenylethanol, 1-phenylpropanol, 1-(1-naphthyl)ethanol and 1- (2-naphthyl)ethanol were substantially higher than those in the corresponding lipase-catalyzed transesterifications. (C) 2000 Elsevier Science Ltd.
- Bakker,Spruijt,Van Rantwijk,Sheldon
-
p. 1801 - 1808
(2007/10/03)
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- Concerted catalytic reactions for conversion of ketones or enol acetates to chiral acetates
-
(matrix presented) Enol acetates or ketones asymmetrically transformed to chiral acetates in high yields with high optical purities through multistep reactions catalyzed by a lipase and a ruthenium complex. 2,6-Dimethylheptan-4-ol was chosen as a suitable hydrogen donor, and 4-chlorophenyl acetate was used as an acyl donor for the conversion of ketones.
- Jung, Hyun M.,Koh, Jeong H.,Kim, Mahn-Joo,Park, Jaiwook
-
p. 409 - 411
(2007/10/03)
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- Convenient Enzymatic Resolution of Alcohols Using Highly Reactive, Nonharmful Acyl Donors, 1-Ethoxyvinyl Esters
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1-Ethoxyvinyl esters 3, a new type of acyl donors for enzymatic resolution of racemic alcohols, were disclosed to be superior to the contemporary major reagents, vinyl esters 1 and isopropenyl esters 2. Three features of 3 are noticeable: (1) 3 generates ethyl acetate as a single coproduct, which does not affect any enzymes, while acetaldehyde liberated from 1 deactivates some kinds of lipases. (2) The reactivity of 3 was not less than that of 1 and much higher than that of 2, and the optical purity of the products was as high as that of 1 and 2. Especially, it was generally observed that 3 showed higher reactivity than 1 for reactions using Candida rugosa lipases, one of the most commonly employed lipases, having liberal applicability to substrates but sensitive to acetaldehyde. Twelve examples of the kinetic resolution of racemic secondary alcohols (5 and 10) and one desymmetrization of meso-alcohol 7 were presented employing the acetate 3a or the octanoate 3b and four types of lipases. (3) A one-pot procedure for the preparation of 3 from the corresponding carboxylic acid and the subsequent enzymatic resolution of alcohols, which has not been reported using 1 or 2, was elucidated. The chemical and optical yields of the products by this procedure were similar to those obtained using isolated 3.
- Kita, Yasuyuki,Takebe, Yasushi,Murata, Kenji,Naka, Tadaatsu,Akai, Shuji
-
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- Enzymatic resolution of secondary alcohols coupled with ruthenium- catalyzed racemization without hydrogen mediator
-
(η5-Indenyl)RuCl(PPh3)2 was found to catalyze the racemization of secondary alcohols in the presence of triethylamine and oxygen. Unlike previously reported metal-catalyzed racemizations, ketones were not required as hydrogen mediators in our process. The Ru-catalyzed racemization was coupled with enzymatic acetylation for the dynamic kinetic resolution of secondary alcohols to give chiral acetates in good yields (60-98%) with high enantioselectivities (82-99% ee).
- Koh, Jeong Hwan,Jung, Hyun Min,Kim, Mahn-Joo,Park, Jaiwook
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p. 6281 - 6284
(2007/10/03)
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- 1-Ethoxyvinyl acetate as a novel, highly reactive, and reliable acyl donor for enzymatic resolution of alcohols
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1-Ethoxyvinyl acetate 3 was found to be a high performance acyl donor for enzymatic resolution of alcohols featuring that (i) 3 shows high reactivity and high selectivity comparable to the most widely used vinyl acetate 1 and (ii) reaction of 3 generates low reactivity ethyl acetate 6 as a single side product, while that of 1 releases unfavorable acetaldehyde 4.
- Kita, Yasuyuki,Takebe, Yasushi,Murata, Kenji,Naka, Tadaatsu,Akai, Shuji
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p. 7369 - 7372
(2007/10/03)
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- Lipase YS-catalysed Acylation of Alcohols: a Predictive Active Site Model for Lipase YS to Identify which Enantiomer of a Primary or a Secondary Alcohol Reacts Faster in this Acylation
-
Primary alcohols having a hydroxymethyl group at an S chiral centre and secondary alcohols with an R configuration are preferentially acylated to give the corresponding acetates by lipase YS-catalysed acylation in diisopropyl ether; a predictive cubic-spaced active site model for lipase YS is proposed for identifying which enantiomer of a primary or a secondary alcohol reacts faster in this acylation.
- Naemura, Koichiro,Fukuda, Ritsuko,Konishi, Masayoshi,Hirose, Keiji,Tobe, Yoshito
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p. 1253 - 1256
(2007/10/02)
-