Process for the preparation of alkali metal salts of 2-phosphonobutane-1,2,4-tricarboxylic acid

US5233088A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Uwe Arndt · Cologne, DE
• Hans-Dieter Block · Cologne, DE
• Roland Kleinstuck · Bensberg, DE

Key dates

• Filing date: Aug 19, 1991
• Grant date: Aug 3, 1993
• Expiry date: Aug 19, 2011

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07F9/3808
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

The present invention relates to a process for the preparation of alkali metal salts of 2-phosphonobutane-1,2,4-tricarboxylic acid, characterized in that 2-phosphonobutane-1,2,4-tricarboxylic acid penta-alkyl esters or partial esters are reacted with an aqueous alkali metal hydroxide solution in a ratio of from 0.5 to 0.76 mol, preferably from 0.6 to 0.7 mol of alkali metal hydroxide per mol of ester function at temperatures from 20.degree. to 200.degree. C. in a one-shot process.