Patent ID: 7081551
Filing Date: 2006-07-25
Classification: C07C

Abstract:
1. A process for producing optically active (R)-1-(4-trifluoromethylphenyl)ethylamine represented by the formula [1], the process comprising the steps of: (a) reacting 4′-(trifluoromethyl)acetophenone represented by the formula [8], with optically active (R)-1-phenylethylamine represented by the formula [9] under an acidic condition to generate a dehydrocondensation, thereby obtaining an optically active imine represented by the formula [2]; (b) asymmetrically reducing the optically active imine into an optically active secondary amine represented by the formula [3]; (c) reacting the optically active secondary amine with an organic acid that is phthalic acid or benzenesulfonic acid, thereby obtaining a product that is a phthalate of the optically active secondary amine or a benzenesulfonate of the optically active secondary amine, the phthalate and the benzenesulfonate being respectively represented by the formulas [4] and [5]; (d) subjecting the product of the step (c) to a hydrogenolysis, thereby obtaining a product that is a phthalate of optically active (R)-1-(4-trifluoromethylphenyl)ethylamine or a benzenesulfonate of optically active (R)-1-(4-trifluoromethylphenyl)ethylamine, the phthalate and the benzenesulfonate being respectively represented by the formulas [6] and [7]; and (e) neutralizing the product of the step (d) into the optically active (R)-1-(4-trifluoromethylphenyl)ethylamine where a zigzag line in the formula [2] indicates that the optically active imine is in an E configuration or Z configuration, where * represents an asymmetric carbon, and the optically active secondary amine comprises a first stereoisomer of R configuration and a second stereoisomer of S configuration, the first stereoisomer is in an amount greater than that of the second stereoisomer.