反应详情

An aqueous solution (1.0 mL) containing 19 mM of N-(2-phenylacetyl)-4-keto-D-proline methyl ester and 19 mM of N-(2-phenylacetyl)-4-keto-L-proline methyl ester in 0.200M sodium acetate (pH 5.0) and 25 mg/mL of Candida antartica lipase fraction B was mixed at 25° C. The reaction mixture was analyzed by mixing with an equivalent volume of 20 mM hexadecane in dichloromethane for 3 minutes, which resulted in the complete extraction of the unreacted D- and L-isomers. The dichloromethane extract was then analyzed by chiral gas chromatography on a Chiraldex G-TA column (Advanced Separation Technologies, Inc., 50 m×0.32 mm ID) to determine the relative amounts of the unreacted D- and L-isomers. After 28 h, 97% of the D-isomer and 28% of the L-isomer remained, yielding a 55% enantiomeric excess of the D-isomer at 38% conversion of the racemic mixture (E=28).

1. additionwas mixed at 25° C
2. customwhich resulted in the complete extraction of the unreacted D- and L-isomers
3. extractionThe dichloromethane extract
4. customwas then analyzed by chiral gas chromatography on a Chiraldex G-TA column (Advanced Separation Technologies, Inc., 50 m×0.32 mm ID)
5. customyielding a 55% enantiomeric excess of the D-isomer at 38% conversion of the racemic mixture (E=28)