Dinuclear Azide-Bridged Copper(II) Complex as Building Block for the Assembly of a 2D-Supramolecular Array

Autor(es)

Alves, Wendel A. ; Sant'Ana, Antonio C. ; Abbott, Mariana P. ; Homem-De-Mello, Paula ; Martinho, Herculano ; Santos, Regina H. A. ; Ferreira, Janaina G. ; Temperini, Marcia L. A. ; Paduan-Filho, Armando ; da Costa Ferreira, Ana Maria

• Tipo de documento: Artigo Científico
• Fonte: Science of Advanced Materials; v. 2, n. 2, p. 11-pg., 2010-06-01.

Resumo

A novel Schiff base-copper(II) complex [Cu2L2(N-3)(2)](ClO4)(2) 1, where L = (4-imidazolyl)ethylene-2-amino-1-ethylpyridine (apyhist), containing azide-bridges between adjacent copper ions in a dinuclear arrangement was isolated and characterized both in the solid state and in solution by X-ray crystallography and different spectroscopic techniques. Azide binding constants were estimated from titrations of the precursor [CuL(H2O)(2)](2+) solutions with sodium azide, giving rise to the azido-bridged species, [Cu2L2(N-3)(2)](2+). Raman spectra showed asymmetric stretching band at 2060 cm(-1), indicating the presence of azido ligands with a symmetric mu(1,) (1) binding geometry. EPA spectra, in frozen methanol/water solutions at 77 K, exhibited characteristic features of copper centers in tetragonal pyramidal coordination geometry, exhibiting magnetic interactions between them. Further, in solid state, two different values for magnetic coupling in this species were obtained, J/k = -(5.14 +/- 0.02) cm(-1) attributed to the mu(1, 1) azide-bridge mode, and J'z'/k = -(2.94 +/- 0.11) cm(-1) for the interaction between dinuclear moieties via water/perchorate bridges. Finally, an attempt was made to correlate structure and magnetic data for this dinuclear asymmetric end-on azido bridged-copper(II) 1 complex with those of another correlated dinuclear system, complex [Cu2L2Cl2](ClO4)(2) 2, containing the same tridentate diimine ligand, but with chloro-bridged groups between the copper centres. (AU)

• Processo FAPESP: 07/05370-0 - Estudo químico-quântico de corantes e de complexos de metais de transição
• Beneficiário: Paula Homem-de-Mello
• Modalidade de apoio: Auxílio à Pesquisa - Jovens Pesquisadores
• Processo FAPESP: 08/53576-9 - Síntese, caracterização e estudo das propriedades eletrônicas dos nanotubos de peptídeos e óxido de titânio
• Beneficiário: Wendel Andrade Alves
• Modalidade de apoio: Auxílio à Pesquisa - Jovens Pesquisadores
• Processo FAPESP: 08/57805-2 - Instituto de Bioanalítica
• Beneficiário: Lauro Tatsuo Kubota
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 05/60596-8 - Espécies complexas com potencial aplicação em bioinorgânica, catálise, farmacologia e química ambiental: concepção, preparação, caracterização e reatividade
• Beneficiário: Ana Maria da Costa Ferreira
• Modalidade de apoio: Auxílio à Pesquisa - Temático