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分别以(8R,10R)-(-)-[4,5]-pineno-2,2′-bipyridine或(8S,10S)-(+)-[4,5]-pineno-2,2′-bipyridine(LRR和LSS)为手性配体合成双核铜络合物[Cu2(μ-ox)(LRR)2(H2O)2(ClO4)2](1)、[Cu2(μ-ox)(LRR)2(CH3COCH3)2(ClO4)2](1a)、[Cu2(μ-ox)(LSS)2(H2O)2(ClO4)2](2)和[Cu2(μ-ox)-(LRR)(LSS)(CH3COCH3)2(ClO4)2](3)(ox2-=草酸根),并探讨了其反应机理.由元素分析、电导率、紫外可见谱(UV-vis)、圆二色(CD)谱和晶体结构分析推测:该系列络合物具有草酸根桥联的双核结构,两个铜(II)离子与草酸根几乎成共平面;1a和3的晶体结构分析表明,每个Cu(II)的配位构型为拉长畸变八面体,双核分子中轴向的两个溶剂分子和两个高氯酸根互为反式配位.对映体络合物1和2的溶液CD光谱大致呈镜像对称,在可见区的极弱CD吸收峰可能源于LRR和LSS蒎烯基上的手性中心对Cu(II)d-d生色团的手性微扰产生的邻位效应.采用最小二乘法和Bleaney-Bowers方程对络合物1的变温磁化率测试数据进行拟合,求得交换积分J=-338.41(4)cm-1,表明铜(II)离子间有较强的反铁磁自旋交换作用.
(5) -pineno-2,2’-bipyridine or (8S, 10S) - (+) - [4,5] -pineno-2,2’- (LRR) 2 (H2O) 2 (ClO4) 2] (1), [Cu2 (μ-ox) (LRR) (2) and [Cu2 (μ-ox) - (LRR) 2] in the presence of Cu2 (μ-ox) (LSS) 2 (H2O) 2 (ClO4) 2] (LSC) (CH3COCH3) 2 (ClO4) 2] (3) (ox2- = oxalate) were synthesized and characterized by elemental analysis, conductivity, UV-vis and circular dichroism CD) spectra and crystal structure analysis suggest that this series of complexes have an oxalate-bridged binuclear structure with two copper (II) ions almost in common with oxalate; the crystal structure analysis of 1a and 3 shows that each Cu (II) is a distorted octahedron in which the two solvent molecules in the axial direction and the two perchlorates are trans-coordinated to each other. The solution CD of the enantiomeric complexes 1 and 2 The spectra are roughly mirror-symmetric and the extremely weak CD absorption peaks in the visible region may result from the ortho-effect of the chiral perturbation of Cu (II) dd chromophores by the chiral centers on the LRR and LSS pinenes. Least square method and Bleaney-Bowers equation for temperature-dependent magnetization of complex 1 Fitting the test data, obtained by the exchange integral J = -338.41 (4) cm-1, showed a strong antiferromagnetic spin-exchange interaction between copper (II) ions.