Preparation of Enantiomerically Pure Compounds Employing Anodic Oxidations of Carboxylic Acids – A Late Review of Research Done in the 1980ies

2019 ◽  
Vol 102 (6) ◽  
Author(s):  
Dieter Seebach
Keyword(s):  
Carboxylic Acids ◽  
Enantiomerically Pure ◽  
Pure Compounds ◽  
Late Review

scholarly journals Altering the Stereoselectivity of Whole-Cell Biotransformations via the Physicochemical Parameters Impacting the Processes

Catalysts ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 781
Author(s):  
Agnieszka Raczyńska ◽  
Joanna Jadczyk ◽  
Małgorzata Brzezińska-Rodak
Keyword(s):  
Culture Conditions ◽  
Biologically Active ◽  
Enantiomerically Pure ◽  
Whole Cells ◽  
Chiral Compounds ◽  
Physicochemical Factors ◽  
Pure Compounds ◽  
Genetic Level ◽  
Prochiral Ketones ◽  
Optically Pure

The enantioselective synthesis of organic compounds is one of the great challenges in organic synthetic chemistry due to its importance for the acquisition of biologically active derivatives, e.g., pharmaceuticals, agrochemicals, and others. This is why biological systems are increasingly applied as tools for chiral compounds synthesis or modification. The use of whole cells of “wild-type” microorganisms is one possible approach, especially as some methods allow improving the conversion degrees and controlling the stereoselectivity of the reaction without the need to introduce changes at the genetic level. Simple manipulation of the culture conditions, the form of a biocatalyst, or the appropriate composition of the biotransformation medium makes it possible to obtain optically pure products in a cheap, safe, and environmentally friendly manner. This review contains selected examples of the influence of physicochemical factors on the stereochemistry of the biocatalytic preparation of enantiomerically pure compounds, which is undertaken through kinetically controlled separation of their racemic mixtures or reduction of prochiral ketones and has an effect on the final enantiomeric purity and enantioselectivity of the reaction.

scholarly journals Asymmetric Mannich reactions of (S)-N-tert-butylsulfinyl-3,3,3-trifluoroacetaldimines with yne nucleophiles

2020 ◽  
Vol 16 ◽  
pp. 2671-2678
Author(s):  
Ziyi Li ◽  
Li Wang ◽  
Yunqi Huang ◽  
Haibo Mei ◽  
Hiroyuki Konno ◽  
...  
Keyword(s):  
Column Chromatography ◽  
Addition Reactions ◽  
Mannich Reactions ◽  
Enantiomerically Pure ◽  
Pure Compounds

In the present work, arylethynes were studied as new C-nucleophiles in the asymmetric Mannich addition reactions with (S)-N-tert-butylsulfinyl-3,3,3-trifluoroacetaldimine. The reactions were conducted under operationally convenient conditions affording the corresponding Mannich adducts with up to 87% yield and 70:30 diastereoselectivity. The isomeric products can be separated using regular column chromatography to afford diastereomerically pure compounds. The purified Mannich addition products were deprotected to give the target enantiomerically pure trifluoromethylpropargylamines. A mechanistic rationale for the observed stereochemical outcome is discussed.

Synthesis of novel chiral fluorescent sensors and their application in enantioselective discrimination of chiral carboxylic acids

2019 ◽  
Vol 43 (9-10) ◽  
pp. 340-346 ◽  
Author(s):  
Qiuhan Yu ◽  
Weiwen Lu ◽  
Zhiqiang Ding ◽  
Min Wei ◽  
Zhenya Dai
Keyword(s):  
Carboxylic Acids ◽  
Chiral Recognition ◽  
Amino Alcohols ◽  
Fluorescent Sensors ◽  
Enantiomerically Pure ◽  
Wide Range

Novel chiral fluorescent sensors are synthesized from a dibromide containing a tetraphenylethylene moiety and enantiomerically pure amino alcohols and an amine. The sensors are applied for the chiral recognition of a wide range of chiral carboxylic acids and related derivatives.

Sign in / Sign up

Export Citation Format

Share Document