Method for the hydrolysis of quinolonecarboxylic esters

US11332444B2 · kind B2 · utility

Assignee

• Bayer Animal Health GmbH · DE

Inventors

• Peter Fey · Wuppertal, DE
• Mathias Berwe · Sprockhövel, DE
• Joerg Wirths · Essen, DE
• Ralf Wischnat
• Markus Longerich · Cologne, DE
• Antje Dietzel · Essen, DE

Key dates

• Filing date: Apr 18, 2019
• Grant date: May 17, 2022
• Expiry date: Apr 18, 2039

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C229/36
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

Quinolonecarboxylic esters of the general formula (II) are hydrolyzed to quinolonecarboxylic acids of the general formula (I):The method comprises the step A):A) reacting compounds of the formula (II) with a mixture comprising acetic acid, sulfuric acid and waterIn step A), ≥30 to ≤40 mol of acetic acid, ≥0.3 to ≤1 mol of sulfuric acid and ≥0.9 to ≤2.5 mol of water are used per mole of compounds of the formula (II). The method is particularly suitable for the synthesis of the intermediate (I) in the synthesis of pradofloxacin.