Separation of diastereomers by extractive distillation

US4874473A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Dieter Arlt · Cologne, DE
• Ulrich Schwartz · Frankfurt am Main, DE
• Hans-Walter Brandt · Odenthal, DE
• Wolfgang Arlt · Hohen Neuendorf, DE
• Andreas Nickel · Winsen (Aller), DE

Key dates

• Filing date: Apr 16, 1987
• Grant date: Oct 17, 1989
• Expiry date: Apr 16, 2007

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C69/743
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

Diastereomers can be separated with good industrial success with the aid of extractive distillation. The separation process is characterized in that an auxiliary which changes the partial pressure of the various diastereomers to be separated to a different degree and thus allows easier separation of the diastereomers by distillation is added during the distillation. Using the present process diastereomic cis/trans-permetric acid methyl esters and mixtures of menthol and isomenthol can be separated with isolation of 99% pure product.