125639-64-7Relevant academic research and scientific papers
Microbial reduction of ethyl 2-oxo-4-phenylbutyrate. Searching for R-enantioselectivity. New access to the enalapril like ACE inhibitors
de Lacerda, Paulo S. Bergo,Ribeiro, Joyce Benzaquem,Leite, Selma G.F.,Ferrara, Maria Antonieta,Coelho, Ricardo B.,Bon, Elba P.S.,da Silva Lima, Edson Luiz,Antunes
, p. 1186 - 1188 (2006)
Herein, different microorganisms were tested in the enantioselective reduction of ethyl 2-oxo-4-phenylbutyrate in aqueous medium for the preparation of ethyl (R)-2-hydroxy-4-phenylbutyrate, a key intermediate in the production of angiotensin converting enzyme (ACE) inhibitors. The use of Pichia angusta led to the (R)-enantiomer in 81% ee.
Ordered mesoporous carbons with Ia3d symmetry supported Pt catalyst for efficient asymmetric hydrogenation
Li, Bo,Li, Xiaohong,Ding, Yue,Wu, Peng
, p. 1033 - 1039 (2012)
Pt nanoparticles supported on CMK-8 ordered mesoporous carbons (OMCs) with Ia3d symmetry after chirally modified with cinchonidine (CD) proved to be highly efficient for asymmetric hydrogenation of α-ketoesters. Up to 34,819 h-1 TOF with 75 % ee was furnished for the enantioselective hydrogenation of ethyl 2-oxo-4-phenylbutyrate with CD-modified Pt/CMK-8 catalyst. To the best of our knowledge, these results obtained with chirally modified Pt/CMK-8 catalyst are the best ones among those with Pt catalysts supported on carbon materials. It is suggested that both the physical structure features ofCMK-8 OMCs and the chemical nature of Pt catalyst are beneficial for the asymmetric hydrogenation.
Significantly enhancing the biocatalytic synthesis of chiral alcohols by semi-rationally engineering an anti-Prelog carbonyl reductase from Acetobacter sp. CCTCC M209061
Wei, Ping,Guo, Ze-Wang,Wu, Xiao-Ling,Liang, Shan,Ou, Xiao-Yang,Xu, Pei,Zong, Min-Hua,Yang, Ji-Guo,Lou, Wen-Yong
, (2019)
Chiral alcohols and their derivatives are vital building blocks to synthesize pharmaceutical drugs and high-valued chemicals. Wild-type carbonyl reductase AcCR from Acetobacter sp. has ideal enantioselectivity toward 11 prochiral substrates (e.e.>99%) but poor activity. In this work, a semi-rational engineering was performed to enhance the activity of AcCR. Fortunately, three positive double-mutants (mut-E144A/G152 L, mut-G152 L/Y189 N, and mut-I147 V/G152 L) with specific activity 17–61 folds higher than that of enzyme without modified were achieved. Kinetic studies suggested that the catalytic efficiencies (kcat/Km) of these mutants were also well enhanced. Finally, these modified mut-AcCRs were successfully applied in asymmetric reductions of 11 structurally diverse prochiral substrates (200 mM) with excellent product yields (76.8%–99.1%) and enantiomeric excess (e.e.>99%), which provides an alternative strategy for efficient synthesis of chiral alcohols for pharmaceuticals industry with ideal yield and enantioselectivity.
Biocatalytic deracemisation of α-hydroxy esters: High yield preparation of (S)-ethyl 2-hydroxy-4-phenylbutanoate from the racemate
Chadha, Anju,Baskar, Baburaj
, p. 1461 - 1464 (2002)
Biocatalytic deracemisaton of the racemic ethyl ester of 2-hydroxy-4-phenylbutanoic acid gives the (S)-enantiomer exclusively in >99% e.e. and 85-90% yield. Ethyl and methyl esters of mandelic acid and the methyl ester of 2-hydroxy-4-phenylbutanoic acid also gave the (S)-enantiomer exclusively. Whole cells of Candida parapsilosis (ATCC 7330) were used to effect this biotansformation.
Effective one-step reduction of Pt/alumina-carbon catalysts for asymmetric hydrogenation of α-ketoesters
Zhang, Xueqin,Li, Qiang,Xiao, Meitian,Liu, Yongjun
, p. 50 - 57 (2014)
Platinum (Pt) particles supported on 15% alumina-carbon composites(Pt/15AM) were reduced by liquid phase reduction methods and one-step high temperature methods. The catalyst was reduced by one-step method with hydrogen at 600°C (Pt/15AM-600) showed superior structure and surface properties such as high special surface area, large pore size, high surface Pt/Al atomic ratio and no residual chlorine on the surface. Moreover, CD-modified Pt/15AM-600 catalyst afforded the highest enantioselectivity of 87.5% and 84.8% in the asymmetric hydrogenation of ethyl pyruvate and EOPB, respectively. Of particular note was the reusability of Pt/15AM-600 catalyst, which could be reused for 23 times without distinct loss in catalytic activity in the asymmetric hydrogenation of ethylpyruvate. The excellent reusability of these alumina-carbon composites supported Pt catalysts indicated the possibility of these novel catalysts in industrial application.
Enhancement of the performance of a platinum nanocatalyst confined within carbon nanotubes for asymmetric hydrogenation
Chen, Zhijian,Guan, Zaihong,Li, Mingrun,Yang, Qihua,Li, Can
, p. 4913 - 4917 (2011)
Going through the proper channels: A highly active and enantioselective heterogeneous asymmetric catalyst was fabricated by confining Pt nanoparticles that are modified with cinchonidine within the channels of carbon nanotubes. A high turnover frequency (TOF) and enantioselectivity are achieved when using this catalyst for the asymmetric hydrogenation of α-ketoesters. Copyright
Pt nanoparticles entrapped in Al2O3?SBA-15 composites: Effective and recyclable catalysts for enantioselective hydrogenation of ethyl 2-oxo-4-phenylbutyrate
Li, Xiaohong,Pan, Huiyan,Wang, Haihong,Wang, Yi Meng,Wu, Peng
, p. 48 - 57 (2014)
Solid-state grinding, ultrasonic impregnation and conventional impregnation methods were adopted to synthesize mesoporous composites Al2O3?SBA-15 supported Pt catalysts for chiral hydrogenation of ethyl 2-oxo-4-phenylbutyrate after modified with cinchonidine. Compared with Pt/SBA-15 or Pt/alumina catalyst, Pt/Al2O3?SBA-15 catalysts afforded better results when alumina loading in Al2O3?SBA-15 composites reached above 15 wt.%. Nevertheless, the catalytic performance of Pt/Al2O3?SBA-15 catalysts was affected by preparation methods for Al2O3?SBA-15 composites. Ultrasonic impregnation of SBA-15 with an aqueous solution of aluminum nitrate led to uniformly dispersed Al2O3?SBA-15 composites and then enhanced the interaction between SBA-15 silica and alumina. Correspondingly, the Pt/Al2O3?SBA-15 catalyst prepared by this method showed the best results (up to 11,928 h?1 TOF and 87.9% ee) and could be reused for several times. Based on the spectroscopic characterizations, we deduced that the acidity of the composites, the Pt particle size and dispersion, and the electronic properties of Pt particles played vital roles in determining the catalytic performance.
Synthesis and application of phosphinoferrocenylaminophosphine ligands for asymmetric catalysis
Boaz, Neil W.,Mackenzie, Elaine B.,Debenham, Sheryl D.,Large, Shannon E.,Ponasik Jr., James A.
, p. 1872 - 1880 (2005)
(Chemical Equation Presented) A new class of bidentate ligands utilizing a phosphine-aminophosphine structure has been prepared on a ferrocenylethyl backbone in a straightforward and scalable fashion from acetylferrocene. The unique property of the α-ferrocenyl carbonium ion that allows the replacement of a variety of "leaving groups" with retention of configuration greatly facilitates the synthesis, and a number of ligands have been prepared by varying the nitrogen and phosphorus substituents on the aminophosphine. These readily prepared phosphinoferrocenylaminophosphines, known as BoPhoz ligands, show surprising hydrolytic and air stability, with no degradation after 3 years open to the air. The rhodium complexes of these ligands show exceedingly high enantioselectivities (generally > 95% ee) and activities often in excess of 50 000 catalyst turnovers per hour for the asymmetric hydrogenation of a wide variety of dehydro-α-amino acid and itaconic acid derivatives. They also show high activity and good to excellent enantioselectivity for the hydrogenation of a number of α-ketoesters.
Exploring the substrate scope of mutants derived from the robust alcohol dehydrogenase TbSADH
Sun, Zhoutong,Li, Guangyue,Ilie, Adriana,Reetz, Manfred T.
, p. 3648 - 3651 (2016)
Directed evolution of an enzyme as catalyst for a given stereoselective transformation provides a mutant for that particular reaction, but organic chemists need catalysts that are characterized by broad substrate acceptance. In a previous study we succeeded in evolving a set of variants of the thermally robust alcohol dehydrogenase TbSADH from Thermoanaerobacter brockii as a catalysts in the (R)- and (S)-selective reduction of tetrahydrofuran-3-one, this difficult-to-reduce compound being a sterically small substrate. These mutants were now tested in the asymmetric reduction of seven structurally unrelated and sterically more demanding substrates, including acetophenone, benzyl methyl ketone, 4-phenyl-2-butanone, and 2-oxo-4-phenyl-butanoic acid ethyl ester. The variants clearly out-perform WT TbSADH, but overly bulky substituted benzophenone derivatives are not accepted by WT or mutants.
Alumina incorporated with mesoporous carbon as a novel support of Pt catalyst for asymmetric hydrogenation
Li, Qiang,Zhang, Xueqin,Xiao, Meitian,Liu, Yongjun
, p. 68 - 72 (2013)
Mesoporous carbon incorporated with different alumina contents has been prepared by chelate-assisted co-assembly method. These composites were used as supports for Pt particles, and the as-prepared catalysts were reduced at 873 K in hydrogen atmosphere. Our current study by using N2 sorption, X-ray diffraction and transmission electron microscopy revealed that carbon incorporated with 10-15 wt% alumina was favorable for the high Pt dispersion and retained the mesostructure of carbon. Moreover, 15 wt% alumina-carbon composite supported Pt particles modified by cinchonidine afforded the highest (84.8%) enantiomeric excess and could be reused at least five times for the asymmetric hydrogenation of ethyl 2-oxo-4-phenylbutyrate in acetic acid.
