SPECTROSCOPIC STUDY OF COPPER(II) COMPLEXES WITH DIHYDROXYPHOSPHORYLMETHYL)-1,4,7-TRIAZACYCLONONANE AND -DIHYDROXYPHOSPHORYLETHYL)-1,4,7-TRIAZACYCLONONANE

The reaction of dihydroxyphosphorylmethyl)-1,4,7-triazacyclononane and -dihydroxyphosphorylethyl)-1,4,7-triazacyclononane with divalent copp er over a wide pH range in aqueous solution has been studied using ele ctronic, vibrational, and ESR spectroscopy. Normal and protonated comp lexes of both compounds have a pentacoordinate structure of the tetrag onal type with coordination of three nitrogen atoms and two phosphonic groups. The difference lies in the different degree of distortion and flexibility of the square-pyramidal polyhedron.