Process for preparing arylaminopropanols

Process for preparing enantiomerically enriched compounds of the formula (I)

• Ar—CH(OH)—CH2—CH2—NR1R2 (I)
• where
• Ar is a substituted or unsubstituted aryl radical and
• R1 and R2 are each independently hydrogen, C1-C20-alkyl, C4-C14-aryl or C5-C15-arylalkyl, or R1 and R2 radicals together are C3-C12-alkylene, comprising
• a) converting compounds of the formula (I) to enantiomerically enriched compounds of the formula (III) or converting compounds of the formula (IV) to enantiomerically enriched compunds of formula (V),
• wherein compounds (II), (Ill), (IV) and (V) are represented as:
• Ar—CO—CH2—COOR3 (II) Ar—CH(OH)—CH2—COOR3 (III) Ar—CO—CH2—CONR1R2 (IV) Ar—CH(OH)—CH2—CONR1R2 (V)
• where, in each case,
• Ar is as defined under the formula (I) and
• R1 and R2 are each as defined under the formula (I) and
• R3 is hydrogen, C1-C20-alkyl, C4-C14-aryl or C5-C15-arylalkyl, and
• where the conversion is effected
• in the presence of a transition metal catalyst
• with hydrogen or a hydrogen-transferring compound or a mixture thereof and
• b) reacting, in the case that compounds of the formula (II) have been used for step a), the enantiomerically enriched compounds of the formula (III) with amines of the formula (VI)
• HNR1R2 (VI)
• where R1 and R2 are each as defined under the formula (I) to give enantiomerically enriched compounds of the formula (V) as defined above and
• c) converting the enantiomerically enriched compounds of the formula (V) by reduction to enantiomerically enriched compounds of the formula (I) as defined above.