Method for resolving optical isomer by using supercritical fluid extraction technology

A method for resolving an optical isomer from a racemate by using a supercritical fluid extraction technique, comprising:

• a) reacting the racemate in the presence of a catalyst to form a mixture comprising a first form of a first optical isomer and a second form of a second optical isomer;
• b) performing an extraction with supercritical fluid on the mixture to allow the first form of the first optical isomer and the second form of the second optical isomer to be separated;
• and
• c) collecting the separated first form of the first optical isomer, and/or collecting the separated second form of the second optical isomer,
• wherein
• the catalyst is an ester hydrolase and/or a lactamase;
• (1) the racemate is DL-pantolactone, the first form of the first optical isomer is D-pantoic acid, and the second form of the second optical isomer is L-pantolactone;
• (2) the racemate is methyl 3-cyclohexene-1-carboxylate, the first form of the first optical isomer is (R)-3-cyclohexene-1-carboxylic acid, and the second form of the second optical isomer is(S)-methyl 3-cyclohexene-1-carboxylate;
• (3) the racemate is α-hydroxy-γ-butyrolactone, the first form of the first optical isomer is (R)-α-hydroxy-γ-butyric acid, and the second form of the second optical isomer is(S)-α-hydroxy-γ-butyrolactone;
• (4) the racemate is β-hydroxy-γ-butyrolactone, the first form of the first optical isomer is (R)-β-hydroxy-γ-butyric acid, and the second form of the second optical isomer is(S)-β-hydroxy-γ-butyrolactone;
• or
• (5) the racemate is α-acetyl-γ-butyrolactone, the first form of the first optical isomer is (R)-α-acetyl-γ-butyric acid, and the second form of the second optical isomer is(S)-α-acetyl-γ-butyrolactone.