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A new dumbbell-type 4,4′-bipy-bridged dinuclear copper(II) complex, [Cu2(4,4′-bipy)L2(H2O)2](ClO4)4·8CH3OH·10H2O, where L = 1-[bis(3-aminopropyl)amino]-2- propanol and bipy = bipyridine, has been synthesized and characterized, X-ray crystallographic analysis shows that the [Cu2(4,4′-bipy)L2(H2O)2]4+ cations and water molecules generate layer structures extending parallel to bc planes through hydrogen bonding interactions of O–H···O and C–H···O. The layers are also connected by hydrogen bonding interactions involving methanol, water, and perchlorate anions. These interactions lead to the formation of rectangular channels of 12.3 A × 6.0 A along the crystallographic c axis. Perchlorate anions fill in each channel in a sandwich-like packing mode, they are joined with the adjacent layers by water heptamers. Magnetic susceptibility measurements show that the magnetic exchange interaction is weak although it has a regular π-type electron transfer pathway. Furthermore, the electrochemical and thermogravimetric properties of the complex were also investigated.

Cubane tetranuclear copper complex [Cu4L4]·5CH3OH·H2O (1; L = 2-(5-fluorosalicylideneamino)ethanol) was synthesized and characterized. The X-ray analysis shows that the coordinative interactions between the copper(II) ions and four oxygen atoms lead to the formation of a cube core in the complex. The coordination polyhedron of each copper ion can be approximately described as a distorted square pyramid with one nitrogen and four oxygen atoms from three ligands. A small molecular cluster, constructed by one water and four methanol molecules, is found in the crystal structure with an average O–O distance of 2.782 A. Magnetic measurements reveal ferromagnetic interactions among the copper atoms.

Two new chiral polymers of different molecular weights were synthesized by the copolymerization of (1R,2R)-(+)-1,2-diphenylethylenediamine, phenyl diisocyanate and terephthaloyl chloride. The polymers were immobilized on aminated silica gel to afford two chiral stationary phases. The polymers and the corresponding chiral stationary phases were characterized by Fourier transform-IR, elemental analysis, 1H and 13C NMR. The surface coverages of chiral structural units on the chiral stationary phases were estimated as 0.27 and 0.39 mmol/g, respectively. The enantioseparation ability of these chiral stationary phases was evaluated with a variety of chiral compounds by high-performance liquid chromatography. The effects of the organic additives, the composition of mobile phases, and the injection amount of sample on enantioseparation were investigated. A comparison of enantioseparation ability between these two chiral stationary phases was made. It was believed that the chain length of polymeric chiral selector significantly affected the enantioseparation ability of corresponding chiral stationary phase.

Two new manganese(II) complexes [MnL1Cl2] and [MnL2Cl]ClO4·MeOH were synthesized [L1 = 1-(benzimidazol-2-ylmethyl)-1,4,7-triazacyclononane; L2 = 1,4-bis(benzimidazol-2-ylmethyl)-1,4,7-triazacyclonone) and characterized by standard physical methods. The new complexes have better stability than the parent complex due to the introduction of benzimidazole groups on the backbone of tacn. The complexes were studied as superoxide dismutase (SOD) mimics by the riboflavin photoreduction method at pH 7.4. In basic or weakly basic solutions, the complexes decompose hydrogen peroxide catalytically, and possess the combined functions of SOD and catalase. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)