Method for the production of phosphonomethylglycine

US6528680B1 · kind B1 · utility

Assignee

• BASF SE

Inventors

• Nicola Christiane Aust · Mendig, DE
• Thomas Butz · Mannheim, DE
• Martin Fischer · Ludwigshafen, DE

Key dates

• Filing date: Feb 4, 2002
• Grant date: Mar 4, 2003
• Expiry date: Feb 4, 2022

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07F9/3813
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

The present invention relates to a process for the preparation of phosphonomethylglycine in which N-phosphonomethyliminodiacetic acid N-oxide is brought into contact with a catalytically active quantity of at least one catalyst, selected from amongst a thionyl halide, ammonium dithionite or an alkali metal dithionite, a dialkyl sulfite, sulfur dichloride, sulfur dioxide and sulfurous acid, in a reaction chamber by metering the N-phosphonomethyliminodiacetic acid N-oxide into the reaction chamber in such a way that always at least 50% of the N-oxide metered into the reaction chamber are converted.