Method for producing optically active 1-phenylethylamines

US6034278A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Walter Merz
• Martin Littmann · Middletown, US
• Udo Kraatz · Leverkusen, DE
• Christoph Mannheims · Leverkusen, DE

Key dates

• Filing date: Dec 17, 1998
• Grant date: Mar 7, 2000
• Expiry date: Dec 17, 2018

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C209/88
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

The invention concerns a new method for producing optically active 1-phenylethylamines, wherein (a) racemic 1-phenylethylamines are reacted with (S)-(-)-N-phenylcarbamate lactic acid in the presence of an aliphatic or aromatic hydrocarbon and in the presence of a lower aliphatic alcohol, wherein the reaction components are measured so that for every mole of racemic amine, between 0.25 and 0.5 mole of (S)-(-)-N-phenylcarbamate lactic acid are present, the reaction mixture is then concentrated at a liquid-phase temperature of up to 40.degree. C., the resulting solid product is separated, treated with diluted, aqueous alkaline lye in the presence of a hydrocarbon, and the respective (R)-amine is isolated by distillation from the organic phase, and if necessary, (b) the mother liquor remaining after the separation of the solid product is reacted in the presence of a lower aliphatic alcohol with (S)-(-)-N-phenylcarbamate lactic acid, wherein the reaction components are measured so that the molar quantity of (S)-(-)-N-phenylcarbamate lactic acid is twice as great as the quantity of (R)-amine still remaining in the mother liquor, the reaction mixture is then concentrated at a liquid-phase…