A Comparative Study of Stabilities and Coordination Modes of beta-Alaninephosphonic Acid in Copper(II) Heteroligand Complexes with Ethylenediamine, Diethylenetriamine or N,N,N ',N ',N ''-Pentamethyldiethylene Triamine in Aqueous Solution

作者：Kamecka Anna^*

来源：Journal of Solution Chemistry, 2012, 41(11): 1948-1964.

DOI：10.1007/s10953-012-9914-4

• Copper(II) complexes
• Heteroligand complexes
• Aminophosphonic acids
• EPR
• Vis spectroscopy
• Potentiometry
• Equilibria
• Stability constants
• Polyamines

Solution equilibrium studies on Cu2+-L-1-L-2 ternary systems have been performed by pH-potentiometry, UV-Vis spectrophotometry and EPR methods {where L-1 corresponds to a polyamine such as ethylenediamine (en), diethylenetriamine (dien), N,N,N',N',NaEuro(3)-pentamethyldiethylenetriamine (Me(5)dien)} and L-2 denotes 2-aminoethylphosphonic acid (beta-alaninephosphonic acid)}. The results suggest the formation of heteroligand complexes with [Cu(L-1)(beta-Ala(P))] stoichiometry in all of the studied systems. Additionally, in the system with en, [Cu(en)(beta-Ala(P))H-1](-) is formed in basic solutions. Our spectroscopic results indicate tetragonal geometry for the [Cu(en)(beta-Ala(P))] species, a geometry slightly deviated from square pyramidal for the [Cu(dien)(beta-Ala(P))] complex, and somewhat stronger geometry distortion was present for the [Cu(Me(5)dien)(beta-Ala(P))] complex. The coordination modes in these heteroligand complexes are discussed.

• 出版日期2012-12