Method of preparing optically pure (R) - or (S) - tetrahydrofuranyl ketone
AssigneeSK Corporation
InventorsHee-Jun Hwang, Jong-Ho Lim
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Abstract
Disclosed is a method of preparing an optically pure (R)- or (S)-tetrahydrofuranyl ketone. By such a method, (R)- or (S)-2-tetrahydrofuran amide is converted to (R)- or (S)-2-tetrahydrofuran nitrile through dehydration in the presence of a dehydrating agent and an amine base. Then, thus prepared (R)- or (S)-2-tetrahydrofuran nitrile is nucelophilic addition-reacted with a nucleophile, followed by hydrolyzing, thereby produce (R)- or (S)-tetrahydrofuranyl ketone having high optical purity, while minimizing production of other by-products.
Claims14
A method of preparing an optically pure (R)-tetrahydrofuranyl ketone, which comprises the following steps of:
- dehydrating (R)-2-tetrahydrofuran amide, represented by the following chemical formula 1a, in the presence of a dehydrating agent and an amine base at 50 to 100° C. for 2 to 6 hours to obtain (R)-2-tetrahydrofuran nitrile represented by the following chemical formula 2a;
- nucelophilic addition-reacting the (R)-2-tetrahydrofuran nitrile with a nucleophile in an organic solvent at the temperature range of −80 to 100° C. for 10 minutes to 4 hours, followed by hydrolyzing by use of aqueous acidic solution to produce (R)-tetrahydrofuranyl ketone represented by the following chemical formula 3a;
- and
- recovering the resulting product obtained from the previous step:
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- wherein, R is a straight-chained or branched, saturated or unsaturated aliphatic alkyl group having 1-30 carbon atoms;
- a saturated or unsaturated, substituted or unsubstituted cyclic alkyl group having 3-30 carbon atoms;
- or a substituted or unsubstituted aryl group having 6-30 carbon atoms.
A method of preparing an optically pure (S)-tetrahydrofuranyl ketone, which comprises the following steps of:
- dehydrating (S)-2-tetrahydrofuran amide represented by the following chemical formula 1b, in the presence of a dehydrating agent and an amine base at 50 to 100° C. for 2 to 6 hours to obtain (S)-2-tetrahydrofuran nitrile represented by the following chemical formula 2b;
- and
- nucelophilic addition-reacting the (S)-2-tetrahydrofuran nitrile with a nucleophile in an organic solvent at the temperature range of from −80 to 100° C. for 10 minutes to 4 hours, followed by hydrolyzing by use of aqueous acidic solution to produce (S)-tetrahydrofuranyl ketone represented by the following chemical formula 3b;
- and
- recovering the resulting product obtained from the previous step:
- 7
- wherein, R is a straight-chained or branched, saturated or unsaturated aliphatic alkyl group having 1-30 carbon atoms;
- a saturated or unsaturated, substituted or unsubstituted cyclic alkyl group having 3-30 carbon atoms;
- or a substituted or unsubstituted aryl group having 6-30 carbon atoms.
Dependencies are inferred from the claim text.