enantiomeric excess


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enantiomeric excess

[ə¦nan·tē·ō¦mer·ik ek′ses]
(organic chemistry)
In an asymmetric synthesis, a chemical yield that contains more of the desired enantiomer than other products.
References in periodicals archive ?
Correlation of such information with the enantiomeric excess obtained in catalytic processes will allow isolating the essential ingredients for stereocontrol.
Intraperitoneal administration of 50% enantiomeric excess (S75-R25) bupivacaine in postoperative analgesia of laparoscopic cholecystectomy.
The senior author recently became fully aware of the following strengths and weaknesses of the previously known lipase-catalyzed (S)-selective acetylation: (i) Enantiomerically pure (R)-2-methyl-1-alkanols can be reliably obtained from their racemic mixtures, although the maximally attainable yield (or recovery) of (R)-alcohols of [greater than or equal to] 98% ee is limited to 50% or, more specifically [less than or equal to] 25% if E = 10, [less than or equal to] 35% if E = 20, and [less than or equal to] 45% if E = 100, where E (enantiomeric ratio or selectivity factor) = ln[(1 - C)(1 - ee)]/ ln[(1 - C)(1 + ee)] and C and ee are the extent of conversion and the enantiomeric excess of the unreacted alcohol, respectively.
Steric effect played an important role in complex formation and achieving good ees as the enantiomeric excess of 1-phenylethanol obtained was maximum 81% for 8 (Entry 5 table 1), which helped us to access structure of the ligands in easy way.
Since this enzyme is the most promiscuous KRED in this library and it often affords alcohols with high enantiomeric excess, it can be a very useful asymmetric catalyst for the synthetic chemist.
To keep pace with this growth, researchers in drug discovery are seeking faster methods to enable higher throughput enantioselective analyses, enantiomeric excess determination and impurity profiling of chiral molecules.
The synthesis of SR, SS of 2-methylsulphinyl-1-indanone optically enriched in good yield and good enantiomeric excess determined by nuclear magnetic resonance technique employing the Kagan reagent as chiral shift agent.
The low baseline noise and high ultraviolet sensitivity is suitable for application areas including enantiomeric excess and trace level analyses.
The objective of this work was to develop a precise and accurate method to determine enantiomeric excess of d-TRS.
This produces a chiral propanoic acid derivative with an enantiomeric excess of either the R or S enantiomer.
The results of the reduction reactions indicated that as the number of stereogenic centers increased at the linking point on the polymer, the % enantiomeric excess of the alcohols produced during the reaction also increased from 13 % enantiomeric excess to 54 % enantiomeric excess.