Stereoselective Synthesis of 3-azabicyclo[3,3,1]Nonan-9α-yl α-(cyclopentyl-1-ene)-α-hydroxy-α-phenylacetate Hydrochloride

The isomers of α-(cyclopentyl-1-ene)-α-hydroxy-α-phenylacetic acid esters derived from 3-azabicyclo[3,3,1]nonan-9α-ol ((R)-1 and (S)-1) were obtained in high enantiomeric excess by effective stereoselective synthesis from the chiral starting material, (S) or (R)-mandelic acid using pivaldehyde as a sterically hindered reagent

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Stereoselective Synthesis of (±)-Ireland Alcohol Using Titanium-Mediated [2,3]Wittig Rearrangement Product as a Starting Material

Bulletin of the Chemical Society of Japan ◽

10.1246/bcsj.65.1841 ◽

1992 ◽

Vol 65 (7) ◽

pp. 1841-1848 ◽

Cited By ~ 8

Author(s):

Satoru Ikegami ◽

Hiroaki Okamura ◽

Satoru Kuroda ◽

Tsutomu Katsuki ◽

Masaru Yamaguchi

Keyword(s):

Stereoselective Synthesis ◽

Starting Material ◽

Rearrangement Product ◽

Wittig Rearrangement

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ChemInform Abstract: CATALYTIC ACTIVATION OF CARBOXYLIC ANIONS IN TWO-PHASE SOLID-LIQUID MEDIA. PREPARATION OF STERICALLY HINDERED CARBOXYLIC ACID ESTERS

Chemischer Informationsdienst ◽

10.1002/chin.197711123 ◽

1977 ◽

Vol 8 (11) ◽

pp. no-no

Author(s):

H. NORMANT ◽

C. LAURENCO

Keyword(s):

Carboxylic Acid ◽

Liquid Media ◽

Two Phase ◽

Catalytic Activation ◽

Sterically Hindered ◽

Solid Liquid ◽

Carboxylic Anions ◽

Acid Esters

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Stereoselective Synthesis of 4H-5,6-Dihydro-1,3-thiazine and 4,5-Dihydrothiazole Derivatives by Use of Imidothioic Acid Esters.

NIPPON KAGAKU KAISHI ◽

10.1246/nikkashi.1996.546 ◽

1996 ◽

pp. 546-558 ◽

Cited By ~ 2

Author(s):

Nobuyuki YASUDA ◽

Michinori KARIKOMI ◽

Takashi TODA

Keyword(s):

Stereoselective Synthesis ◽

Acid Esters

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Enantioselective Equilibration−Access to Chiral Aldol Adducts of Mandelic Acid Esters

Organic Letters ◽

10.1021/ol062252w ◽

2006 ◽

Vol 8 (23) ◽

pp. 5353-5355 ◽

Cited By ~ 7

Author(s):

Stefan Scholtis ◽

Andreas Ide ◽

Rainer Mahrwald

Keyword(s):

Mandelic Acid ◽

Acid Esters

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Copper-catalyzed intramolecular redox reaction: Asymmetric synthesis of chiral 2-(1H-pyrrol-1-yl)-mandelic acid esters

Tetrahedron ◽

10.1016/j.tet.2018.11.024 ◽

2018 ◽

Vol 74 (52) ◽

pp. 7480-7484

Author(s):

Hong-Jin Du ◽

Chao Lin ◽

Xiaoan Wen ◽

Qing-Long Xu

Keyword(s):

Asymmetric Synthesis ◽

Redox Reaction ◽

Mandelic Acid ◽

Acid Esters

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Comparative Analysis of the Conversion of Mandelonitrile and 2-Phenylpropionitrile by a Large Set of Variants Generated from a Nitrilase Originating from Pseudomonas fluorescens EBC191

Molecules ◽

10.3390/molecules24234232 ◽

2019 ◽

Vol 24 (23) ◽

pp. 4232 ◽

Cited By ~ 2

Author(s):

Stolz ◽

Eppinger ◽

Sosedov ◽

Kiziak

Keyword(s):

Pseudomonas Fluorescens ◽

Mandelic Acid ◽

Single Point ◽

Enantiomeric Excess ◽

Point Mutations ◽

General Information ◽

Large Set ◽

Single Point Mutations ◽

Aliphatic Nitriles ◽

Relationship Of

The arylacetonitrilase from the bacterium Pseudomonas fluorescens EBC191 has been intensively studied as a model to understand the molecular basis for the substrate-, reaction-, and enantioselectivity of nitrilases. The nitrilase converts various aromatic and aliphatic nitriles to the corresponding acids and varying amounts of the corresponding amides. The enzyme has been analysed by site-specific mutagenesis and more than 50 different variants have been generated and analysed for the conversion of (R,S)-mandelonitrile and (R,S)-2-phenylpropionitrile. These comparative analyses demonstrated that single point mutations are sufficient to generate enzyme variants which hydrolyse (R,S)-mandelonitrile to (R)-mandelic acid with an enantiomeric excess (ee) of 91% or to (S)-mandelic acid with an ee-value of 47%. The conversion of (R,S)-2-phenylpropionitrile by different nitrilase variants resulted in the formation of either (S)- or (R)-2-phenylpropionic acid with ee-values up to about 80%. Furthermore, the amounts of amides that are produced from (R,S)-mandelonitrile and (R,S)-2-phenylpropionitrile could be changed by single point mutations between 2%–94% and <0.2%–73%, respectively. The present study attempted to collect and compare the results obtained during our previous work, and to obtain additional general information about the relationship of the amide forming capacity of nitrilases and the enantiomeric composition of the products.

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Directed Iridium‐Catalyzed Hydrogen Isotope Exchange Reactions of Phenylacetic Acid Esters and Amides

Chemistry - A European Journal ◽

10.1002/chem.201901449 ◽

2019 ◽

Vol 25 (26) ◽

pp. 6517-6522 ◽

Cited By ~ 13

Author(s):

Mégane Valero ◽

Daniel Becker ◽

Kristof Jess ◽

Remo Weck ◽

Jens Atzrodt ◽

...

Keyword(s):

Hydrogen Isotope ◽

Isotope Exchange ◽

Phenylacetic Acid ◽

Exchange Reactions ◽

Hydrogen Isotope Exchange ◽

Acid Esters

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Rhodium-Catalyzed Asymmetric Addition of Arylboronic Acids to Glyoxylates: Access to Optically Active Substituted Mandelic Acid Esters

Synlett ◽

10.1055/s-0037-1610722 ◽

2019 ◽

Vol 30 (14) ◽

pp. 1693-1697

Author(s):

Diao Chen ◽

Jian-Guo Liu ◽

Xu Zhang ◽

Ming-Hua Xu

Keyword(s):

Catalytic System ◽

Mandelic Acid ◽

Optically Active ◽

Antiplatelet Drug ◽

Reaction Conditions ◽

Formal Synthesis ◽

Arylboronic Acids ◽

Synthetic Utility ◽

Enantioselective Addition ◽

Acid Esters

A rhodium-catalyzed enantioselective addition of glyoxylates to arylboronic acids promoted by a simple chiral sulfinamide-based olefin ligand under mild reaction conditions is described. The reaction provides access to a variety of optically active substituted mandelic acid esters in good yields with up to 83% ee. The catalytic system is also applicable to pyruvate addition. The synthetic utility of this method is highlighted by a formal synthesis of the antiplatelet drug clopidogrel.

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