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Non-peripherally tetradodecyloxy substituted copper (CuPc 3) and nickel (NiPc 4) phthalocyanines and the compounds were synthesized. The absorption spectra of synthesized Pcs were showed monomeric behavior evidenced by a narrow between 680 and 750 nm (Q band) for CuPc(3) and NiPc(4) in different solvents. The fluorescence behavior of the Pcs was studied in chloroform. The CuPc (3) showed outstanding stability in THF as solvent during photodegradation studies. The possible photodynamic therapy reaction mechanisms were studied through the calculation of ionization potentials and electron affinity in both vacuum and solvents using SCRF model. [ABSTRACT FROM AUTHOR]

The critical micelle concentrations (CMC) of three metallosurfactant Schiff base cobalt(III) complexes of the type [Co(trien)(CHNO)]Cl,[Co(trien) (CHNO)]Cl and [Co(trien)(CHNO)]Cl, where trien = triethylenetetramine, have been studied in n-alcohol and in formamide at different temperatures by the electrical conductivity method. CMCs have also been measured as a function of percentage concentration of alcohol in the mixed solvents with formamide. Specific conductivity data (at 303-323 K) served for the evaluation of the temperature-dependent CMC and thermodynamic parameters such as the standard Gibbs energy changes ( $\Delta G^{\circ}_{\mathrm{mic}})$, enthalpy changes ( $\Delta H^{\circ}_{\mathrm{mic}})$, and entropy changes ( $\Delta S^{\circ}_{\mathrm{mic}})$ of micelle formation. It is suggested that addition of an alcohol leads to increased penetration of formamide into the micellar interface, the extent depending on the alcohol's chain length. The results have been discussed in terms of the solvophobic interaction, dielectric constant of the medium, the chain length of the alcohol, and the surfactant in the solvent mixture. [ABSTRACT FROM AUTHOR]

Metallosurfactant complexes of the type trans- [Co(DH)(HA)X], where DH = Dimethyl glyoxime, HA = Hexadecyl amine and X = Cl, Br, I, N, NO or SCN, were synthesized and characterized by physico-chemical and spectroscopic methods. In addition, the single crystal X-ray structure of the ionic complex trans-[Co(DH)(HA)][Co(DH)(I))] is presented. The critical micelle concentration values of the complexes in ethanol were obtained by measuring the absorption at 290 nm. Specific conductivity data (at 303-313 K) served for the evaluation of the thermodynamics of micellization $$ \left( {\Updelta G^{0}_{{{\text{m}}}}, \Updelta H^{0}_{{{\text{m}}}}, \Updelta S^{0}_{\text{m}} } \right) $$. Steady-state photolysis, cyclic voltammetry and biological activities of the complexes were studied. The compounds were tested for antimicrobial activity. [ABSTRACT FROM AUTHOR]

The critical micelle concentration (CMC) of four kinds of metallosurfactants of the type halogeno(dodecyl/cetylamine)-bis(ethylenediamine)cobalt(III) has been studied in n-alcohol and in formamide at different temperatures by electrical conductivity method. Specific conductivity data (at 293–313 K) served for the evaluation of temperature-dependent CMC and the thermodynamic parameters such as standard Gibbs free energy changes (ΔG0mic), enthalpies (ΔH0mic), and entropies (ΔS0mic) of micelle formation. CMCs have also been measured as a function of percentage concentration of alcohol added. It is suggested that alcohol addition leads to increase in formamide penetration into micellar interface that depends on the alcohol chain length. The results have been discussed in terms of increased hydrophobic effect (solvophobic interaction), dielectric constant of the medium, and the chain length of the alcohols, the surfactant in the solvent mixture. © 2006 Wiley Periodicals, Inc. Int J Chem Kinet 39: 22–31, 2007 [ABSTRACT FROM AUTHOR]

Kinetics of reduction of the surfactant complex ions, cis-chloro/bromo (dodecylamine)bis(ethylenediamine)cobalt(III) by iron(II) in aqueous solution was studied at 303, 308, and 313 K by spectrophotometry method under pseudo-first-order conditions, using an excess of the reductant. The second-order rate constant remains constant below critical micelle concentration (cmc), but increases with cobalt(III) concentration above cmc, and the presence of aggregation of the complex itself alters the reaction rate. The rate of reaction was not affected by the added [H+]. Variation of ionic strength (μ) influences the reaction rate. Activation and thermodynamic parameters have been computed. It is suggested that the reaction of Fe2+ (aq) with cobalt(III) complex proceeds by the inner-sphere mechanism. © 2005 Wiley Periodicals, Inc. Int J Chem Kinet 38: 98–105, 2006 [ABSTRACT FROM AUTHOR]