10606-72-1Relevant articles and documents
Enantioselective catalytic synthesis of ethyl mandelate derivatives using Rh(I)-NHC catalysts and organoboron reagents
Marques, Carolina S.,Burke, Anthony J.
, p. 628 - 632 (2013)
Herein we describe for the first time the enantioselective catalytic arylation of ethyl glyoxalate using phenylboron reagents and chiral rhodium(I)-NHC catalysts. KOtBu was the base of choice, along with tert-amyl alcohol as the solvent. A novel chiral bis-imidazolium salt was synthesized and evaluated for the first time in this catalytic transformation. Although moderate enantioselectivities (up to 34% ee) were obtained for the phenylation reaction, despite the excellent yields, very low enantioselectivities were obtained using other arylboronic acids with a variety of chiral rhodium(I)-NHC catalysts.
Chiral-at-Iron Catalyst: Expanding the Chemical Space for Asymmetric Earth-Abundant Metal Catalysis
Hong, Yubiao,Jarrige, Lucie,Harms, Klaus,Meggers, Eric
, p. 4569 - 4572 (2019)
A new class of chiral iron catalysts is introduced that contains exclusively achiral ligands with the overall chirality being the result of a stereogenic iron center. Specifically, iron(II) is cis-coordinated to two N-(2-pyridyl)-substituted N-heterocycli
Copper encapsulated alkaloids composite: An effective heterogeneous catalyst for electrocatalytic asymmetric hydrogenation
Yang, Heng-Pan,Fen, Qiu,Wang, Huan,Lu, Jia-Xing
, p. 38 - 42 (2016)
A novel heterogeneous catalyst, alkaloid@Cu was prepared by the entrapment of commercially purchased alkaloids within non-noble metallic copper nanoparticles. This composite was compacted into a coin and directly used as cathode for electrocatalytic asymmetric hydrogenation of aromatic ketones. Using water as hydrogen source, optically active alcohols with 71% ee value and 93% yield were obtained under very mild conditions.
Stereocontrolled reduction of α- and β-keto esters with micro green algae, Chlorella strains
Ishihara, Kohji,Yamaguchi, Hitomi,Adachi, Noriko,Hamada, Hiroki,Nakajima, Nobuyoshi
, p. 2099 - 2103 (2000)
The stereocontrolled reduction of α- and β-keto esters using micro green algae was accomplished by a combination of the cultivation method and the introduction of an additive. The reduction of ethyl pyruvate and ethyl benzoylformate by the photoautotrophically cultivated Chlorella sorokiniana gave the corresponding alcohol in high e.e. (>99% e.e. (S) and >99% e.e. (R), respectively). In the presence of glucose as an additive, the reduction of ethyl 3-methyl-2-oxobutanoate by the heterotrophically cultivated C. sorokiniana afforded the corresponding (R)-alcohol. On the other hand, the reduction in the presence of ethyl propionate gave the (S)-alcohol. Ethyl 2-methyl-3-oxobutanoate was reduced in the presence of glycerol by the photoautotrophically cultivated C. sorokiniana or the heterotrophically cultivated C. sorokiniana to the corresponding syn-(2R,3S)-hydroxy ester with high diastereo- and enantiomeric excess (e.e.). Some additives altered the stereochemical course in the reduction of α- and β-keto esters.
Enantioselective synthesis of ethyl (S)-2-hydroxy-4-phenylbutyrate by recombinant diketoreductase
Wu, Xuri,Wang, Yuchen,Ju, Jianming,Chen, Chen,Liu, Nan,Chen, Yijun
, p. 2504 - 2509 (2009)
Recombinant diketoreductase showed excellent stereoselectivity in the double reduction of β,δ-diketo esters. To investigate the substrate specificity and to broaden the applications of this new biocatalyst, a number of ketone substrates were used to evaluate the substrate spectrum and enantioselectivity of this enzyme in the present study. Among the ketone substrates tested, only this enzyme displayed high efficiency and excellent enantioselectivity in the reduction of ethyl 2-oxo-4-phenylbutyrate to ethyl (S)-2-hydroxy-4-phenylbutyrate. After optimizing the reaction conditions, the bio-reduction of ethyl 2-oxo-4-phenylbutyrate at a substrate concentration of 0.8 M (164.8 g/L) was achieved by the recombinant diketoreductase in an aqueous-toluene biphasic system coupled with formate dehydrogenase for the regeneration of cofactor, resulting in an overall hydroxyl product yield of 88.7% (99.5% ee). This new enzymatic transformation may offer a practical method for the preparation of this important chiral building block.
Alkaloid-induced asymmetric hydrogenation on a Cu nanoparticle cathode by electrochemical conditions
Yang, Heng-Pan,Wang, Huan,Lu, Jia-Xing
, p. 18 - 21 (2015)
Copper nanoparticles were prepared in an aqueous solution, compacted into a coin, and used as a cathode for asymmetric hydrogenation by the electrochemical method for the first time. A good ee value and excellent yield were obtained under mild conditions. Electrochemical conditions were crucial for alkaloid adsorption on metallic Cu, which is a key process of asymmetric induction. Furthermore, the ee value was linear with an adsorption amount.
Biocatalysed reductions of α-ketoesters employing CyreneTM as cosolvent
de Gonzalo, Gonzalo
, (2021)
The search for novel reaction media with environmental friendly properties is an area of great interest in enzyme catalysis. Water is the medium of biocatalysed processes, but due to its properties, sometimes the presence of organic (co)solvents is required. CyreneTM represents one of the newest approaches to this medium engineering. This polar solvent has been employed for the first time in biocatalysed reductions employing purified alcohol dehydrogenases. A set of α-ketoesters has been reduced to the corresponding chiral α-hydroxyesters with high conversions and optical purities, being possible to obtain good results at Cyrene contents of 30% v/v and working at substrate concentrations of 1.0 M in presence of 2.5% v/v of this solvent. At this concentration, the presence of Cyrene has a beneficial effect in the bioreduction conversion.
Enantioselective hydrogenation of α-ketoesters over alkaloid-modified platinum nanowires
Erathodiyil, Nandanan,Gu, Hongwei,Shao, Huilin,Jiang, Jiang,Ying, Jackie Y.
, p. 3070 - 3074 (2011)
A green process for enantioselective hydrogenation of α-ketoesters over cinchona alkaloid-modified platinum (Pt) nanowires has been developed. Pt nanowires with a diameter of ～1 nm were successfully synthesized, and used for the asymmetric hydrogenation of α-ketoesters in the presence of cinchona alkaloids under a low pressure at room temperature in water. Quantitative yields and excellent enantioselectivity of up to 78% were achieved. The catalyst along with the modifier was recycled multiple times without any significant loss in activity or selectivity. To our knowledge, such a catalyst system is unprecedented for asymmetric hydrogenation of α-ketoesters. The Royal Society of Chemistry.
Efficient heterogeneous asymmetric transfer hydrogenation catalyzed by recyclable silica-supported ruthenium complexes
Liu, Pei-Nian,Gu, Pei-Ming,Deng, Jin-Gen,Tu, Yong-Qiang,Ma, Ya-Ping
, p. 3221 - 3227 (2005)
Easily accessible N-(p-tolylsulfonyl)-1,2-diphenylethylenediamine-(TsDPEN-) derived organic-inorganic hybrid ligands were prepared and applied to the heterogeneous asymmetric transfer hydrogenation in traditional HCO 2H/NEt3 and in w
Compensation effect between differential activation enthalpy and entropy in subtilisin-catalyzed kinetic resolutions of secondary alcohols
Ema, Tadashi,Yamaguchi, Kunihiro,Wakasa, Yuji,Tanaka, Nobuaki,Utaka, Masanori,Sakai, Takashi
, p. 782 - 783 (2000)
Thermodynamic parameters for subtilisin-catalyzed kinetic resolutions of secondary alcohols were determined, and a compensation effect between ΔΔH? and ΔΔS? was found. These data are explained in terms of the transition-state model.
Kinetics and catalyst deactivation in the enantioselective hydrogenation of ethyl benzoylformate over Pt/Al2O3
Martin, Gerson,Maeki-Arvela, Paeivi,Murzin, Dmitry Yu.,Salmi, Tapio
, p. 170 - 178 (2014)
The enantioselective hydrogenation of ethyl benzoylformate (EBF) to (R)-ethyl mandelate(-)-cinchonidine (CD)-modified Pt/Al2O 3 catalyst in toluene in a semi-batch reactor was studied as a function of modifier concentration, reaction temperature, stirring rate and catalyst particle size. The kinetic results showed higher enantioselectivity and lower initial rates tending asymptotically to a constant value as the amount of modifier increased. The maximum enantiomeric excess (ee) and the initial hydrogenation rate or turnover frequency obtained under optimized conditions with an initial concentration of 5.6 mmol L-1 EBF at 25°C5% (w/w) Pt/Al2O3 were 85% (modifier-to-surface Pt of 1.28) and 109 h-1 (modifier-to-surface Pt of 0.16), respectively. Additionally, catalyst deactivation due to the presence of impurities in the feed was prominent in some cases; therefore activated carbon was used as a cleaning agent of the raw material to remove impurities prior to catalyst addition.
Enantioselective α-hydroxylation of 2-arylacetic acid derivatives and buspirone catalyzed by engineered cytochrome P450 BM-3
Landwehr, Marco,Hochrein, Lisa,Otey, Christopher R.,Kasrayan, Alex,Baeckvall, Jan-E.,Arnold, Frances H.
, p. 6058 - 6059 (2006)
Here we report that an engineered microbial cytochrome P450 BM-3 (CYP102A subfamily) efficiently catalyzes the α-hydroxylation of phenylacetic acid esters. This P450 BM-3 variant also produces the authentic human metabolite of buspirone, R-6-hydroxybuspir
Bioreduction with Immobilized Bakers' Yeast in Hexane using Alcohols as an Energy Source
Naoshima, Yoshinobu,Maeda, Jusei,Munakata, Yoshihito,Nishiyama, Tadashi,Kamezawa, Makoto,Tachibana, Hojun
, p. 964 - 965 (1990)
Bioreduction with immobilized bakers' yeast proceeded smoothly in hexane by using alcohols, such as methanol, ethanol, and propan-2-ol, instead of glucose, as an energy source; ethyl 3-oxobutanoate and ethyl benzoylformate were each reduced to the corresp
Solvent effects in the enantioselective hydrogenation of ethyl benzoylformate
Martin, Gerson,Maeki-Arvela, Paeivi,Murzin, Dmitry Yu.,Salmi, Tapio
, p. 1051 - 1060 (2013)
Solvent effects in the enantioselective hydrogenation of ethyl benzoylformate (EBF) to (R)-ethyl mandelate(-)-cinchonidine (CD)-modified Pt/Al2O3 catalyst were studied in a semi-batch reactor. Solvents of different nature were used:
Mandelohydroxamic acid as ligand for copper(II) 15-metallacrown-5 lanthanide(III) and copper(II) 15-metallacrown-5 uranyl complexes
Parac-Vogt, Tatjana N.,Pacco, Antoine,Nockemann, Peter,Yuan, Yao-Feng,Goerller-Walrand, Christiane,Binnemans, Koen
, p. 1466 - 1474 (2006)
The formation of pentanuclear copper(II) complexes with the mandelohydroxamic ligand was studied in solution by electrospray ionization mass spectrometry (ESI-MS), absorption spectrophotometry, circular dichroism and 1H NMR spectroscopy. The pr
Structure-guided evolution of carbonyl reductase for efficient biosynthesis of ethyl (: R)-2-hydroxy-4-phenylbutyrate
Chen, Chao,Chen, Lulu,Deng, Jian,Kuang, Yuyao,Lin, Jinping,Tang, Wen,Wang, Hualei,Wei, Dongzhi,Yin, Bo
, p. 7512 - 7522 (2020)
Ethyl (R)-2-hydroxy-4-phenylbutanoate ((R)-HPBE) is an important versatile intermediate for the synthesis of angiotensin-converting enzyme inhibitors. Herein, a structure-guided rational design was adopted to improve the catalytic performance of carbonyl reductase from Gluconobacter oxydans (GoCR) for efficient production of (R)-HPBE at high substrate loading. To enhance the catalytic performance of GoCR, three sites (Cys93, Ile187 and Trp193) were identified based on a computational approach. Through single-site and cooperative mutation at these three sites, four variants with simultaneous increase in stereoselectivity and catalytic efficiency were obtained. Variants mut-W193L, mut-W193L/C93I, mut-W193L/I187L and mut-W193L/C93I/I187L exhibited 9.8-to 37.0-fold increase in catalytic efficiency (kcat/Km) compared to the wild-type enzyme. Meanwhile, the stereoselectivities of these variants were improved from 43.0% ee of wild-type GoCR to >99% ee. In addition, mut-W193L/C93I/I187L displayed improved thermostability simultaneously. Theoretical structural analysis revealed that the changes in the catalytic pocket microenvironment resulted in the concurrent improvement of enzyme activity and thermostability. In the batch production of (R)-HPBE, up to 371 g L-1 substrate loading was completely reduced by utilizing the most efficient variant mut-W193L/C93I/I187L at 40 °C, affording (R)-HPBE with >99% ee and a space-time yield of 540.4 g L-1 per day. This study provides a potential and attractive biocatalyst for the efficient synthesis of (R)-HPBE.
High Enantioselectivity in Reductions with a Chiral Polymethylene-Bridged Bis(NADH) Model Compound
Seki, Masahiko,Baba, Naomichi,Oda, Jun'ichi,Inouye, Yuzo
, p. 1370 - 1373 (1983)
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ASYMMETRIC OXIDATION OF OLEFINS WITH OSMIUM TETROXIDE COORDINATED BY CHIRAL DIAMINES DERIVED FROM L-TARTARIC ACID
Yamada, Tohru,Narasaka, Koichi
, p. 131 - 134 (1986)
The enantioselective oxidation of olefins with OsO4 coordinated by chiral diamines derived from L-tartaric acid is described.Phenylketene dimethylacetal and trans-stilbene are converted to (R)-methyl mandelate and (1R,2R)-1,2-diphenyl-1,2-ethanediol with
Chiral ferrocene-indole diphosphine ligand as well as preparation method and application thereof
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Paragraph 0079-0080, (2021/05/22)
The invention relates to a chiral ferrocene-indole diphosphine ligand as well as a preparation method and application thereof. The specific preparation method comprises the following steps: dissolving an indole compound and a chiral ferrocene phosphine ac
