Patent ID: 7026515

Claim:
A process for preparing an optically active aminoalcohol wherein an optically active 5-oxazolidinone derivative represented by general formula (1): wherein R 1 represents an unprotected or optionally protected side chain in a natural α-amino acid; and R 2 represents optionally substituted aryl, optionally substituted alkyl, or optionally substituted aralkyl, is reacted with an organometallic reagent represented by general formula (2): R 3 —M (2) wherein R 3 represents optionally substituted aryl or optionally substituted heterocycle; M represents one selected from the group consisting of Li, MgX, ZnX, TiX 3 and CuX; and X represents halogen, to form an optically active 5-hydroxyoxazolidine derivative represented by general formula (3): wherein R 1 , R 2 and R 3 are as defined above, which is then treated under acidic conditions to give an optically active aminoketone derivative represented by general formula (4): wherein R 1 and R 3 are as defined above; and R 4 represents hydrogen or optionally substituted alkyloxycarbonyl, optionally substituted aryloxycarbonyl or optionally substituted aralkyloxycarbonyl as a protective group, which is then treated with a reducing agent or catalytically hydrogenated with a metal catalyst to stereoselectively provide an optically active aminoalcohol derivative represented by general formula (5): wherein R 1 , R 3 and R 4 are as defined above; provided that configuration of R 1 attached to the asymmetric carbon at 4-position and the substituent represented by a nitrogen atom in the optically active 5-oxazolidinone represented by general formula (1) is not changed throughout these reactions and relative configuration between the amino group and the hydroxy group in the optically active aminoalcohol represented by general formula (5) is an erythro configuration.