METHOD OF OBTAINING AMINOHYDROXYDIPHOSPHONIC ACIDS Russian patent published in 2015 - IPC C07F9/38 C07F9/58 C07F9/59 

FIELD: chemistry.

SUBSTANCE: invention relates to a method of obtaining aminohydroxydiphosphonic acids for application in the chemical industry. Claimed is obtaining aminohydroxydiphosphonic acid by the interaction of the respective aminocarboxylic acid and P₄O₆ at 40°C-180°C in the presence of sulphonic acid. Aminocarboxylic acid and P₄O₆ are used in molar ratios from 4:1 to 1:1, from 1 to 30 equivalents of sulphonic acid being used per mole of aminocarboxylic acid. Aminocarboxylic acid has formula (A)(B)N-X¹-COOH, D-X²-COOH or E-X³-COOH, where X¹ and X² are optionally substituted linear, branched, cyclic or aromatic groups, which have from 2 to 20 carbon atoms; A and B are selected from H or an optionally substituted branched, linear, cyclic, aromatic, heterocyclic or heteroaromatic group, which has from 1 to 20 carbon atoms; D represents an optionally substituted 4-8-membered heteromonocyclic or heteromonoaromatic group, which is bound to X² via a nitrogen atom, where the substituent can be condensed with D; or D together with X² represent an imide; X³ represents a bond or an optionally substituted C₁-C₂₀ linear, branched, cyclic or aromatic hydrocarbon group, E is an optionally substituted heterocyclic or heteroaromatic 4-14-membered ring, bound to X³ via a carbon atom; heterocyclic and heteroaromatic groups contain from 1 to 4 heteroatoms, selected from N, S and O, the difference between the number of atoms and heteroatoms in the cycles is not less than 2.

EFFECT: claimed is the novel selective method of obtaining valuable aminohydroxydiphosphonic acids.

15 cl, 5 ex, 3 tbl