Patent ID: 6121487
Filing Date: 2000-09-19
Classification: C07C,C25B

Abstract:
A method of producing enantiomer-enriched amino acids and amino-acid derivatives of formula (I) or acid addition salts thereof ##STR13## in which *=center of asymmetryX=O or NHR.sup.1 =H, (C.sub.1 -C.sub.6) alkyl, benzyl or (C.sub.3 -C.sub.6) alkoxycarbonylmethyl, andR.sup.2 =H or (C.sub.1 -C.sub.6) alkyl, which can be interrupted or substituted with heteroatoms, which heteroatoms can be substituted themselves singly or multiply with (C.sub.1 -C.sub.3) alkyl, (C.sub.2 -C.sub.6) alkenyl, (C.sub.1 -C.sub.6) haloalkyl, halogen, aryl, which can be substituted singly or multiply with (C.sub.1 -C.sub.3) alkyl, hydroxy, halogen or (C.sub.1 -C.sub.3) alkoxy, aralkyl, which for its part can be substituted singly or multiply with (C.sub.1 -C.sub.3) alkyl, hydroxy, halogen or (C.sub.1 -C.sub.3) alkoxy, heteroaralkyl, andR.sup.3 signifies H, OH,from diastereomer-enriched nitrons of the general formula (II) ##STR14## in which * and R.sup.1 have the significance indicated above, whereinthe nitron of the general formula (II) is reacted with a hydrazine derivative of the general formula (III) ##STR15## in which R.sup.2 has the meaning indicated above in a solvent in the presence of a radical starter or under electrochemical conditions to obtain diastereomer-enriched compounds of the general formula (IV) ##STR16## in which R.sup.1 and R.sup.2 have the meanings indicated above and R.sup.3 =OH, and the resulting product is subsequently hydrolyzed or first reduced to compounds of the general formula (IV), in which R.sup.1 and R.sup.2 have the meanings indicated above and R.sup.3 =H, and then hydrolyzed.