Influence of a Pyrazyl Linker on the Physicochemical Properties of Homodinuclear Bis(cyclen) and Bis(cyclam) Complexes
作者:Sanae El Ghachtouli、Cyril Cadiou、Isabelle Déchamps‐Olivier、Françoise Chuburu、Michel Aplincourt、Thierry Roisnel、Véronique Turcry、Véronique Patinec、Michel Le Baccon、Henri Handel
DOI:10.1002/ejic.200800149
日期:2008.10
CuII and NiII complexes of bis(cyclen)pyrazine and bis(cyclam)pyrazine, [Cu2L1]4+, [Ni2L1]4+, [Cu2L2]4+, [Ni2L2]4+, have been isolated and characterised by UV/Vis and EPR spectroscopy. Complex [Cu2L1]4+ was characterised by X-ray diffraction. The crystallographic structure indicated that the two metal cations are held in a square-pyramidal geometry, the central nitrogen pyrazine atoms occupying the
双(环烯)吡嗪和双(环氨)吡嗪的 CuII 和 NiII 配合物,[Cu2L1]4+, [Ni2L1]4+, [Cu2L2]4+, [Ni2L2]4+,已被分离出来并通过紫外/可见光表征和 EPR 光谱。复合物 [Cu2L1]4+ 通过 X 射线衍射表征。晶体结构表明,两种金属阳离子呈方形锥体几何结构,中心氮吡嗪原子占据每个金属中心的顶端位置。在溶液中,[Cu2L1]4+ 的 EPR 光谱显示存在两种异构体,其中一种是之前的结晶复合物。对于[Ni2L2]4+,电化学研究强调了复合物存在两种不同的几何结构(III 型和 V 型)。从电子的角度来看,EPR 和电化学测量表明,在这些配合物中,吡嗪桥在两个金属中心之间表现为低效的交换桥配体。(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)