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The properties of Cu(II) and Co(II) complexes with oxygen- or nitrogen-containing macrocycles have been extensively studied; however, less attention has been paid to the study of complexes containing sulfur atoms in the first coordination sphere. Herein we present the interaction between these two metal ions and two macrocyclic ligands with N2S2 donor sets. Cu(II) and Co(II) complexes with the pyridine-containing 14-membered macrocycles 3,11-dithia-7,17-diazabicyclo[11.3.1]heptadeca-1(17), 13,15-triene (L) and 7-(9-anthracenylmethyl)-3,11-dithia-7,17-diazabicycio[11.3.1]heptadeca- 1(17),13,15-triene (L1) have been synthesized. The X-ray structural analysis of {[Co(ClO4)(H2O)(L)][Co(H2O)2(L)]} (ClO4)3 shows two different metal sites in octahedral coordination. The EPR spectra of powdered samples of this compound are typical of distorted six-coordinated Co(II) ions in a high-spin (S = 3/2) configuration, with the ground state being S = 1/2 (g1 = 5.20, g2 = 3.20, g3 = 1.95). The EPR spectrum of [Cu(ClO4)(L)] (ClO4) was simulated assuming an axial g tensor (g1 = g2 = 2.043, g3 = 2.145), while that of [Cu(ClO 4)(L1)](ClO4) slightly differs from an axial symmetry (g1 = 2.025, g2 = 2.060, g3 = 2.155). These results are compatible with a Cu(II) ion in square-pyramidal coordination with N2S2 as basal ligands. Single-crystal EPR experiment performed on [Cu(ClO4)(L1)](ClO4) allowed determining the eigenvalues of the molecular g tensor associated with the copper site, as well as the two possible orientations for the tensor. On the basis of symmetry arguments, an assignment in which the eigenvectors are nearly along the Cu(II)-ligand bonds is chosen. Fil: Tamayo, Isabel Cristina. Faculdade de Ciências E Tecnologia, Universidade Nova de Lisboa; Portugal. Universitat Autònoma de Barcelona; España Fil: Casabó, Jaume. Universitat Autònoma de Barcelona; España Fil: Escriche, Lluís. Universitat Autònoma de Barcelona; España Fil: González, Pablo Javier. Universidad Nacional del Litoral; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Lodeiro, Carlos. Faculdade de Ciências E Tecnologia, Universidade Nova de Lisboa; Portugal Fil: Rizzi, Alberto Claudio. Universidad Nacional del Litoral; Argentina Fil: Brondino, Carlos Dante. Universidad Nacional del Litoral; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Passeggi, Mario Cesar Genaro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina Fil: Kivekäs, Raikko. Helsingin Yliopisto; Fil: Sillanpää, Reijo. Universidad de Jyvaskyla; Finlandia |
