| 摘要 |
PROBLEM TO BE SOLVED: To provide a new optically active cyclic amino acid ester derivative easily producible from a disubstituted aliphatic carboxylic acid and useful as an intermediate for an optically active cyclic amino acid which is useful as an intermediate for pharmaceuticals, agrochemicals, etc. SOLUTION: The objective compound is expressed by formula I [R1 is a 1-8C alkyl; R2 is H a 1-8C alkyl, a halogen or the like; R3 is an aryl or a (substituted)1-8C alkyl; (n) is 1-4; (a) and (b) each represents asymmetric carbon atom], e.g. N-[(S)-α-methylbenzyl]-(S)-proline methyl ester. The compound can be produced by reacting a disubstituted aliphatic carboxylic acid ester of formula III (Y is an eliminable group) (e.g. methyl 2,5-dichlorovalerate) with an optically active amine of formula III [e.g. (S)-α-methylbenzylamine] in a solvent such as methanol at -50 to +200 deg.C. |
