Process for the manufacture of 1-aminoalkane-1,1-diphosphonic acids

US4418019A · kind A · utility

Assignee

• Hoechst GmbH · DE

Inventors

• Werner Klose · Lechenich, DE
• Theodor Auel · Ilvesheim, DE

Key dates

• Filing date: Dec 7, 1981
• Grant date: Nov 29, 1983
• Expiry date: Dec 7, 2001

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07F9/3873
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

The invention relates to a process for making 1-aminoalkane-1,1-diphosphonic acids of the general formula (I): ##STR1## in which R stands for an aliphatic hydrocarbon radical having from 1 to 12 carbon atoms. To this end, the invention provides: PA1 (a) for tetraphosphorus hexoxide to be reacted with at least one compound of the general formula (II) ##STR2## in which R has the meaning given above and X stands for an --ONH.sub.4 or NH.sub.2 -radical, in inert gas atmosphere at elevated temperature, the molar ratio of tetraphosphorus hexoxide to the compound of general formula (II) being about 1 to 2-6; and PA1 (b) for 1-aminoalkane-1,1-diphosphonic acid to be crystallized from the reaction mixture.