Method for the manufacture of aminohydroxy diphosphonic acids

摘要

The technology of this invention concerns a method for the manufacture of hydroxy diphosphonic acids containing an amino moiety. The method specifically involves reacting a liquid P4O6 with an aminocarboxylic acid in the presence of a sulfonic acid. The aminocarboxylic acid is selected from 3 structurally different compounds. The amino hydroxy diphosphonic acids can be synthesized with high selectivity and purity and the unreacted starting raw materials can easily and conveniently be recirculated.