Process for producing optically active amines
AssigneeBayer Aktiengesellschaft
InventorUwe Stelzer
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Abstract
The present invention provides a novel process for producing known optically active amines and optically active acylated amines by: a) in a first step, reacting racemic amines with esters, in the presence of hydrolases and possibly a diluent; b) in a second step, separating the reaction mixture into (S)-amine and acylated (R)-amine; and c) optionally in a third step releasing (R)-amine from acylated (R)-amine by treatment with an acid or base, possibly in the presence of a diluent. The optically active amines can be employed as intermediates for preparing pharmaceuticals and crop protection agents.
Claims4
A process for preparing an optically active amine of the formula
- wherein
- R represents a radical of the formula
- —(CH2)m—R2, and
- R2 represents optionally substituted phenyl of the formula
- wherein
- R7, R8 and R9 independently of one another each represent hydrogen, halogen, alkyl having 1 to 4 carbon atoms, alkoxy having 1 to 4 carbon atoms, alkylthio having 1 to 4 carbon atoms, halogenoalkyl having 1 to 4 carbon atoms and 1 to 5 identical or different halogen atoms, halogenoalkoxy having 1 to 4 carbon atoms and I to 5 identical or different halogen atoms, cyano, dialkylamino having 1 to 4 carbon atoms in each alkyl group, nitro, phenyl, phenoxy or benzyl, and
- m represents the numbers 0, 1, 2 or 3, and
- R1 represents hydrogen, comprising the steps of
- a) reacting in a first step, a racemic amine of the formula
- wherein
- R and R1 are each as defined above with an ester of the formula
- wherein
- R3 represents chloromethyl or a radical of the formula —CH2—CN, or
- R3 represents a radical of the formula —CH2—COOR6, wherein
- R6 represents methyl, ethyl, n-propyl or n-butyl, and
- R4 represents methyl, ethyl, n-propyl, or n-butyl, in the presence of lipase from Candida antarctica and in the presence of a diluent,
- b) separating, in a second step, the resulting mixture of (S)-amine of the formula
- wherein
- R and R1 are each as defined above, and separating the acylated (R)-amine of the formula
- wherein
- R, R1 and R3 are each as defined above, and
- c) if appropriate, setting free, in a third step, the (R)-amine of the formula
- wherein
- R and R1 are each as defined above, from the acylated (R)-amine of the formula (III) by treatment with an acid or a base, if appropriate in the presence of a diluent.
Process according to claim 9, characterized in that the first step is carried out at temperatures between 0° C. and 80° C.
Dependencies are inferred from the claim text.