Enzymatic kinetic resolution of secondary alcohols by esterification with FA under vacuum
Abstract Kinetic resolution of some chiral secondary alcohols [2‐octanol, 1‐phenylethanol, and 1‐(2‐naphthyl)ethanol] with high enantioselectivity ( E >300) was achieved by direct esterification with FFA catalyzed by immobilized Candida antarctica B lipase. The reaction equilibrium was shifted to...
Published in: | Journal of the American Oil Chemists' Society |
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Main Authors: | , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Wiley
2003
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Subjects: | |
Online Access: | http://dx.doi.org/10.1007/s11746-003-0755-4 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1007%2Fs11746-003-0755-4 https://onlinelibrary.wiley.com/doi/full/10.1007/s11746-003-0755-4 |
Summary: | Abstract Kinetic resolution of some chiral secondary alcohols [2‐octanol, 1‐phenylethanol, and 1‐(2‐naphthyl)ethanol] with high enantioselectivity ( E >300) was achieved by direct esterification with FFA catalyzed by immobilized Candida antarctica B lipase. The reaction equilibrium was shifted toward the synthetic side by the removal of the water formed under vacuum. Esterification of rac ‐2‐octanol at an alcohol/FFA molar ratio of 2∶1 was used as a model reaction. The chain length of FFA and their structure influenced the reaction rate but did not have a measureable effect on E . The best acyl donor was decanoic acid: >47% conversion at 4 h with virtually perfect E . Temperature did not affect E in the range studied (15–45°C), but temperatures at the higher end afforded improved reaction rates. The reaction rates and E were compared for three different acyl donors. The initial reaction rate increased in the following order: ethyl laurate < lauric acid < vinyl acetate. E was high ( E >300) for all acyl donors. Racemic 1‐phenylethanol and 1‐(2‐naphthyl)ethanol were also resolved by direct esterification with decanoic acid in short times (3 and 4 h, respectively) with E >300 and excellent conversions. Preparative‐scale kinetic resolution of 2‐octanol was also performed. |
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