文摘
The new copper(II) or copper(II)/sodium(I) 1D coordination polymers [Cu2(Hmdea)2(-H2O)(2-tpa)]n·2nH2O (1),[Cu2(H2tipa)2(2-ipa)]n·4nH2O (2), [Cu2(H2tea)2Na(H2O)2(2-tma)]n·6nH2O (3), [Cu2(H2tea)2(2-ipa)]n·nH2O (4a), and[Cu2(H2tea)2{3-Na(H2O)3}(3-ipa)]n(NO3)n·0.5nH2O (4b) have been prepared in aqueous medium by self-assemblyfrom copper(II) nitrate, aminopolyalcohols [methyldiethanolamine (H2mdea), triisopropanolamine (H3tipa), andtriethanolamine (H3tea)] as main chelating ligands and benzenepolycarboxylic acids [terephthalic (H2tpa), isophthalic(H2ipa), and trimesic (H3tma) acid] as spacers. They have been characterized by IR spectroscopy, elemental andsingle-crystal X-ray diffraction analyses, the latter indicating the formation of unusual multinuclear metal coresinterconnected by various benzenepolycarboxylate spacers, leading to distinct wavelike, zigzag, or linear 1D polymericmetal-organic chains. These are further extended to 2D or 3D hydrogen-bonded supramolecular networks viaextensive interactions with the intercalated crystallization water molecules. The latter are associated, also withaqua ligands, by hydrogen bonds resulting in acyclic (H2O)3 clusters in 1, (H2O)8 clusters in 2, infinite 1D waterchains in 3, and disordered water-nitrate associates in 4b, all playing a key role in the structure stabilization andits extension to further dimensions. Variable-temperature magnetic susceptibility measurements have shown that1-4 exhibit a moderately strong ferromagnetic coupling through the alkoxo bridge. The small Cu-O-Cu bridgingangle and the large out-of-plane displacement of the carbon atom of the alkoxo group accounts for this behavior.The magnetic data have been analyzed by means of a dinuclear and a 1D chain model, and the magnetic parametershave been determined. The magnetic exchange coupling in 3, to our knowledge, is the highest found in alkoxo-bridged copper(II) complexes.
