BINDING OF HEXACYANOFERRATE(II) BY ALIPHATIC-AMINES IN AQUEOUS-SOLUTION

The stability of hexacyanoferrate(II)-amine(methylamine, ethylenediami ne, diethylenetriamine and tetraethylenepentamine) was determined pote ntiometrically. Species Fe(CN)(6)(A)H-j((j-4)) (A = amine) are formed in all the systems investigated, with j = 1 ... n + 2 (n = number of a minogroups). Some other complexes Fe(CN)(6)(A)(i)H-j (with i > 1) were also found The stability of these complexes is fairly high: the full protonated amine species, show for the reaction Fe(CN)(6)(4-) + H(n)A( n+) = Fe(CN)(6)(A)H-n((n-4)) an equilibrium constant given by logK = 0 .686 + 2.10n. Factors affecting the stability are discussed in compari son with similar systems, together with the importance of interference s.