Solvent Effect on Stability and Thermodynamic Behavior of Complex of 18-Crown-6 with Hydroxyl Ammonium Cation

Document Type: Research Article

Authors

Department of Chemistry, Faculty of Sciences, University of Sistan and Baluchestan, Zahedan, I.R. IRAN

Abstract

The complexation reaction between hydroxyl ammonium (HONH3+ ) cation with 18-crown-6 (18C6) ligand was studied in dimethylsulfoxide – water (DMSO-H2O), methanol – water (MeOH-H2O) and dimethylformamid – methanol (DMF-MeOH), binary solutions at different temperatures using conductometric method. The obtained results show that the stoichiometry of the complex formed between HONH3+ cation with (18C6 ) in all of the binary mixed solvents is 1:1[ML], as well as, these results show that the nature and the composition of the solvent systems are important factors that are effective on the stability of the complex formed between the macrocyclic ligand and metal cation in solutions. A non-linear behavior was observed for changes of stability constants of the complex versus the composition of the binary mixed solvents. The values of thermodynamic parameters show that  the  thermodynamics  of  complexation  reaction is affected by the nature and composition of the mixed solvents and the complex is entropy stabilized, but enthalpy destabilized in most compositions of binary solutions.

Keywords

Main Subjects


[1] Davidson R.B., Izatt R.M., Christensen J.J., Schultz R.A., Dishong D.M., Gokel G.W., Stability Constants, Enthalpies, and Entropies for Metal Ion-Lariat Ether Interactions in Methanol Solution, J. Org. Chem., 49: 5080-5084 (1984).

[2] Arnold K.A., Echegoyen L., Gokel G.W.J.,Determination of Thermodynamic Parameters  in Lariat Ether Complexes Using Ionselective Electrodes, Am. Chem. Soc., 109: 3713-3715 (1987).

[3] Matthes D., Parker H., Buschmann J., Ferguson G., Structure and Complexation Behaviour of Calcium-Selective [12]-N2O2 Macrocycles Incorporating Amide Substituents, Tetrahedron Lett., 28: 5573–5576 (1987).

[4]  Taghdiri M., Payehghadr M., Behjatmanesh-Ardakani R., Movahhedi S., Nourifard F., Conductometric Studies of Thermodynamics of 1,10-Didecyl-1,10-diaza-18-crown-6 Complexes with Li+, Na+, K+, Cs+, NH4+, Mg2+, and Ca2+ Ions in Acetonitrile, Methanol, and Ethanol Solutions, J. Chem- Hind. Pub. Corp., 2013, 1-9 (2012).

[6] Rounaghi G.H., Deiminiat B., Study of Complexation Process Between N-Phenylaza-15-Crown-5 with Yttrium Cation in Binary Mixed Solvents, J. Incl. Phenom. Macrocycl. Chem., 72: 113-119 (2012).

[7] Rounaghi G.H., Mohajeri M., Tarahomi S., Rahmanian R., Study of Complex Formation of Dibenzo-18-Crown-6 with Ce3+, Y3+, UO22+ and Sr2+ Cations in Acetonitrile-Dioxane Binary Solvent Mixtures, J. Solution Chem., 40: 377-389 (2011).

[11]  Razghandi F., Rounaghi G.H., Mohammadzadeh Kakhki R., Complexation Study of Dibenzo-18-Crown-6 with UO22+ Cation in Binary Mixed Non-Aqueous Solutions, J. Incl. Phenom. Macrocycl. Chem., 73: 279-286 (2012).

[20] Lada E., Xiubin L., Kalinowski M., Electrochemical Study of 18-Crown-6-Tl+ Complexes in Binary Solvent Mixtures, Monatsh. Chem., 123: 425-433 (1992).

[22] Krestov G.A., Novosyolov N.P., Perelygin I.S., “Ionic Solvation”. Ellis Horwood, New York (1994).

[23] Szyman´ska-Cybulska J., Kamien´ska-Piotrowicz E., Solvation of Cobalt(II) ion in N, N-Dimethylformamide-Methanol Mixed Solvent Calorimetry and VIS Spectroscopy Studies, J. Solut. Chem., 35: 1631-1643 (2006).

[24] Izatt R.M., Pawlak K., Bradshaw J.S., Bruening R.L., Tarbet B.J., Thermodynamic and Kinetic Data for Macrocycle Interaction with Neutral Molecules, Chem. Rev., 92: 1261-1354 (1992).

[27] Izatt R.M., Bradshaw J.S., Nielsen S.A., Lamb J.D., Christensen J.J., Thermodynamic and Kinetic Data for Cation-Macrocycle Interaction, Chem. Rev., 85: 271-339 (1985).

[28] Buschmann H.J., Mutihac R.C., Schollmeyer E., Complex Formation of 18-Crown-6 with Metal Cations and Ammonium Ions in Dioxane-Water Mixtures, Thermochim. Acta., 472: 17-19 (2008).

[29] Steffens J.E., Khazaeli S., Thermodynamics of Cesium Cation Complexation with Dibenzo-24-crown-8 in Mixed Nonaqueous Solvents, J. Incl. Phenom., 22: 171-186 (1995).