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The structure of the complex [CuII(PuPy)](ClO4)2 (PuPy = L = 1,8-bis(2-pyridyl)-2,7-diazaoctadiene-1,7) and the structure of the corresponding copper(I) complex were determined. In CuIIL(ClO4)2, a model compound with CuZnSOD activity, the unit CuIIL2+ has a tetrahedrally distorted square-planar N4 coordination geometry. The copper(I) complex with L was found to be dimeric, (CuIL)2(ClO4)2.DMF (DMF = N,N-dimethylformamide). The binuclear unit (CuIL)2(2+) has a helical structure with two ligands L bridging the two copper atoms to provide tetrahedral N4 coordination of each copper(I). In solutions of (CuIL)2(ClO4)2.DMF, solvent-dependent dissociation occurs according to D reversible 2M (D = (CuIL)2(2+); M = CuILSx+; S = solvent). Stopped-flow spectrophotometry was used to determine the rate constants for the dissociation of the dimer D (kM) and dimerization of the monomer M (kD) for S = acetonitrile and DMF. Equilibrium constants Kdim = kM/kD were determined spectrophotometrically. In aqueous solution, the oxidation of the dimer (CuIL)2(2+) by CoIII(NH3)5Cl2+ and cis- and trans-CoIII(en)2Cl2+ follows a second-order rate law, rate = kox[(CuIL)2(2+)][Co(III)]. Data for rate constant kox and for the activation parameters delta H++ and delta S++ are presented. In DMF, the oxidation of (CuIL)2(2+) by CoIII(NH3)5Cl2+ occurs via the monomer CuIL(DMF)x+ and the dissociation of (CuIL)2(2+) becomes rate-controlling. The reduction of CuIIL2+ by RuII(edta)H2O2- was found to be too fast to be resolved by stopped-flow spectrophotometry. The kinetic results are discussed mechanistically in terms of the redox switch aspects of the system.

Summary: Experimental data for the photopolymerization of furfuryl acrylate (FA) conformed satisfactorily to the kinetics model proposed for the photopolymerization of furfuryl methacrylate (FM). This model allowed the kinetic constants of the basic steps of the studied mechanism, namely propagation, degradative transfer, re‐initiation and cross‐termination, to be determined. The calculated values of these constants were in agreement with the chemical nature of FA. For each of these constants, the confidence intervals were determined, and the statistical dependence between some of them was analyzed using the ellipse error method. The equations of moments of the distribution of molecular sizes of the primary chains in the network with order greater than one were developed to describe different molecular averages, such as weight‐average chain length and size‐average heterogeneity of the primary chains. The results found for the monomer conversion, the cross‐link degree and number‐average length of the primary chains of the network for FA were compared with those obtained for FM, and it was shown that the process of polymerization of the former monomer was more retarded and produced gels with a greater degree of cross‐linking than the latter as expected.

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This study focuses on the estimation and validation of some interaction parameters of the Consistent Valence Force‐Field (CVFF), which are required for the calculation of thermodynamic and transport properties of oxaliplatin (a colorectal anticancer drug) in poly(lactic‐co‐glycolic) acids (PLGAs) matrices. Our methodology to validate the parameters for PLGAs consisted on calculation of glass transition temperature and correlations between structural properties as: fractional free volume, polymer density, and cohesive energy density using Molecular dynamic simulations. For the oxaliplatin, metal‐dependent and independent interaction parameters were included into CVFF and validated with an ab‐initio method (RHF/LanL2DZ). The results achieved in the present work showed that the CVFF has been wellparameterized.