Complexes of Cu^II with mixed-donor phenanthroline-containing macrocycles: analysis of their structural, redox and spectral properties in the context of Type-1 blue copper proteins biomimeti

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• 作者：Arca ; Massimiliano ; Azimi ; Gholamhassan ; Demartin ; Francesco ; Devillanova ; Francesco A. ; et. al.
• 关键词：Macrocycles ; Phenanthroline ; Type-1 blue copper proteins ; X-ray diffraction
• 刊名：Inorganica Chimica Acta
• 出版年：2005
• 出版时间：April 15, 2005
• 年：2005
• 卷：358
• 期：7
• 页码：2403-2412
• 全文大小：252 K

文摘

The macrocycles L¹aaaL³ having N₂S₂O-, N₂S₂-, and N₂S₃-donor sets, respectively, and incorporating the 1,10-phenanthroline unit interact in EtOH and MeCN solutions with Cu^II to give 1:1 [M(L)]²⁺ complex species. The compounds [Cu(L¹)(ClO₄)]ClO₄ (1), [Cu(L²)(ClO₄)]ClO₄aa Formula Not Shown (2) and [Cu(L³)](ClO₄)₂ (3) were isolated at the solid state and the first two also characterised by X-ray diffraction studies. The conformation adopted by L¹ and L² in the cation complexes reveals the aliphatic portion of the rings folded over the plane containing the heteroaromatic moiety with the ligands encapsulating the metal centre within their cavity by imposing, respectively, a square-based pyramidal and a square planar geometry. In both complexes, the metal ion completes its coordination sphere by interacting with a ClO₄^aaa ligand. The compound [Cu(L³)₂](PF₆)₂ (4) containing a 1:2 cation complex was also isolated at the solid state: EPR spectroscopy measurements suggest the presence of a CuN₄ chromophore in this complex. The EPR and electronic spectral features of 1aaa4 have been studied and their redox properties examined in comparison with those observed for Type-1 blue copper proteins.