The novel dinuclear copper complex [Cu2(H2O)2(DMF)2(L)2](1, H2 L = 5-phenyl-2H-1,2,3-triazole-4-carboxylic acid, DMF = N,N-dimethyl-formamide) has been synthesized and characterized by X-ray single-crystal diffraction. The compound crystallizes in triclinic system, space group P1 with a = 9.591, b = 10.508, c = 15.515 ?, β = 75.11°, V = 1446.2 ?3, Z = 2, Mr = 683.62, Dc = 1.570 g/cm3, μ = 1.531 mm-1, F(000) = 700, the final R = 0.0404 and w R = 0.1130 for 5327 observed reflections with I > 2σ(I). In each unit of the complex, two Cu2+ ions coordinated with two triazole ligands to form a dimeric [5,6,5] tricyclic structure. The central Cu atom is five-coordinated, and each copper atom shows a square pyramidal geometry. The crystal structure is stabilized by the inversion-related O–H···O hydrogen bond and C–H···O hydrogen bonding interactions to form a layer structure. Fluorescent spectra show an obvious quenching of fluorescence compared with free 1,2,3-triazole ligand. The results of agarose gel electrophoresis indicate that this complex can cleave the plasmid supercoiled DNA within shorter time in the 50-folds excess of ascorbate under physiological conditions, providing a new example in the research for artificial metal nucleic acid enzyme.
LIU Wen-QianZHOU Shi-LeiFAN Ming-ZhuPAN Zhi-QuanCHEN Yun-Feng
A new dinuclear copper(Ⅱ)compound[Cu2(CH3COO)2(L)2(H2O)2]·4H2O(1,HL=4-pyridyl-NH-1,2,3-triazole)has been synthesized and characterized.Single-crystal X-ray diffraction showed that complex 1 crystallizes in monoclinic space group P21/c with a=0.8427(1),b=1.0981(1),c=1.3610(1)nm,β=93.364(4)°,V=1.2573(1)nm^3,Mr=643.56,Z=2,Dc=1.700 g/cm^3,μ=1.760 mm-1,R=0.0376,wR=0.0981,and possesses a planar Cu2N4 six-membered ring,in which both Cu(Ⅱ)ions are bridged by two 1,2,3-triazole ligands.The neighboring dinuclear molecules are bound by strong intermolecular hydrogen bonds to create 1-D chains expanding along the b axis,which further form a 3-D supramolecular framework.Magnetic susceptibility measurement indicated the presence of weak antiferromagnetic interactions within the complex.The best fit using spin Hamiltonian yields the magnetic coupling constant J=–14.82 cm^-1 above 30 K.The magnetic data are compared to those obtained for related double diazine bridged dinuclear copper(Ⅱ)complexes and magnetostructural correlations are discussed.
