Preparation of amorphous water-soluble complexes of biometals with (1-hydroxyethylidene)diphosphonic acid, 2-aminoethanol, and 2-amino-2-(hydroxymethyl)propane-1,3-diol

Multifold enhancement of solubility in water of Fe(III) and Mn(II) complexes with (1-hydroxyethylidene) diphosphonic acid has been achieved by their transformation into the corresponding salts via interaction of aqueous suspensions of the poorly soluble complexes with 2-aminoethanol and 2-amino-2-(hydroxymethyl)propane-1,3-diol. Molecular structure of tris(2-hydroxyethanaminium)(1-hydroxyethylidene)-diphosphonate has been determined. Potential agricultural efficiency of the prepared iron and manganese derivatives as well as zinc and copper complexes with (1-hydroxyethylidene)diphosphonic acid as a microfertilizer has been estimated.