Method of producing new derivatives of the amino-methylene-bis-phosphonic acid.

摘要

The method of producing new derivatives of the amino-methylene-bis-phosphonic acid with the general formula presented in the figure: where R1 refers to a hydrogen atom, a phenyl, a phenyl with one or two atoms of chlorine or bromine as substituents, a phenyl with a nitrite group as a substituent, benzyl, a cycloalkyl with three to six atoms of carbon or an alkyl with one to six atoms of carbon; R2 refers to an atom of hydrogen or R1R2 constitute an oxy-diethylene bridge. Characterized in that: Aliphatic, alicyclical or aromatic amine, alkyle orthoformate and dialkyl phosphite, preferably a diethylic one, are heated up to the boiling point. Then, the raw product of the reaction is hydrolysed with hydrochloric acid and the product is precipitated by crystallisation or ion-exchange chromatography.