PROCESS FOR THE MANUFACTURE OF 1-AMINOALKANE-1,1- DIPHOSPHONIC ACIDS

摘要

PROCESS FOR THE MANUFACTURE OF 1-AMINOALKANE-1,1 DIPHOSPHONIC ACIDS The invention relates to a process for making 1-amino-alkane-1,1-diphosphonic acids of the general formula (I) (I) in which R stands for an aliphatic hydrocarbon radical having from 1 to 12 carbon atoms. To this end, the invention provides: a) for tetraphosphorus hexoxlde to be reacted with at least one compound of the general formula (II) (II) in which R has the meaning given above and X stands for an-ONH4 or NH2-radical, in inert gaq atmosphere at elevated bemperature, the molar ratio of tetraphosphorus hexoxide to the compound of general formuls (II): being about 1 to 2-6; and b) for 1-aminoalkane-1,1-diphosphonic acid to be crystalli zed from the reaction mixture.