Patent ID: 8383833

Claim:
A method for producing an optically active N-protected α-amino acid ester compound, comprising the steps of a) reacting an α-haloester compound represented by the formula (1): wherein, R 1 is an optionally substituted alkyl group having 1 to 12 carbon atoms, an optionally substituted aryl group having 6 to 14 carbon atoms, or an optionally substituted aralkyl group having 7 to 15 carbon atoms; R 2 is an optionally substituted alkyl group having 1 to 12 carbon atoms, an optionally substituted aryl group having 6 to 14 carbon atoms, or an optionally substituted aralkyl group having 7 to 15 carbon atoms; Y is an optionally substituted alkyloxy group having 1 to 12 carbon atoms, an optionally substituted monoalkylamino group having 1 to 12 carbon atoms, or an optionally substituted dialkylamino group having 1 to 12 carbon atoms wherein the alkyl moieties in dialkylamino group may link together to form a heterocycle; X is a halogen atom; * indicates an asymmetric carbon atom, with an amine compound represented by the formula (2): HNR 3 R 4 (2) wherein, one of R 3 and R 4 is an optionally substituted aryl group having 6-14 carbon atoms, and the other is a hydrogen atom, an optionally substituted alkyl group having 1 to 12 carbon atoms, an optionally substituted aryl group having 6 to 14 carbon atoms, an optionally substituted aralkyl group having 7 to 15 carbon atoms, a sulfonyl group or a carbonyl group; and R 3 may be linked with R 4 to form a ring, to obtain an optically active N-protected α-amino acid ester compound represented by the formula (3): wherein, R 5 is an optionally substituted alkyl group having 1 to 12 carbon atoms, an optionally substituted aryl group having 6 to 14 carbon atoms, or an optionally substituted aralkyl group having 7 to 15 carbon atoms or may be linked with R 6 to form a ring; one of R 6 and R 7 is an optionally substituted aryl group having 6 to 14 carbon atoms, and the other is a hydrogen atom, an optionally substituted alkyl group having 1 to 12 carbon atoms, an optionally substituted aryl group having 6 to 14 carbon atoms, an optionally substituted aralkyl group having 7 to 15 carbon atoms, a sulfonyl group or a carbonyl group or R 6 may be linked with R 5 to form a ring; R 7 may be linked with R 6 to form a ring; R 2 and Y are the same as the above; * indicates an asymmetric carbon; b) conducting ester exchange of the above N-protected α-amino acid ester compound represented by the formula (3) with an alcohol represented by the formula (4): R 8 OH (4) wherein, R 8 is an optionally substituted alkyl group having 1 to 12 carbon atoms, an optionally substituted aryl group having 6 to 14 carbon atoms, or an optionally substituted aralkyl group having 7 to 15 carbon atoms; wherein the optically active N-protected α-amino acid ester compound is represented by the formula (5): wherein, R 5 , R 6 , R 7 , R 8 and * are the same as the above.