Synthesis, crystal structure and magnetic properties of a dinuclear and a trinuclear Ni(II) complexes derived from tetradentate ONNO donor Mannich base ligands
hand, compound 2 possesses a centrosymmetric trinuclear structure where two distorted square pyramidal terminal Ni(II) centres are connected to a central octahedral Ni(II) via phenoxido bridge. Here SCN − ligand occupies the axial positions of the terminal Ni(II) centres by coordinating through N atom. Variable temperature magnetic susceptibility measurements of solid samples reveal that the Ni(II) paramagnetic
摘要[Ni 2(HL 1)2(NCS)2]·CH 2 Cl 2(1)和[Ni 3(L 2)2(NCS)2(H 2 O)2]·CH 3 CN( 2)已使用两种不同的四齿ONNO供体曼尼希碱配体N,N'-双(3,5-二甲基-2-羟基苄基)-N,N'-二甲基乙二胺(H 2 L 1)和N,N'-双(3-甲氧基-5-甲基-2-羟基苄基)-N,N′-二甲基乙二胺(H 2 L 2)。化合物1为μ1,1异硫氰酸根桥联的双核化合物,而化合物2为以SCN-为末端配体的苯氧基桥联的三核化合物。在化合物1中,来自每个配体的两个苯氧基氧原子之一保持质子化,因此使该化合物电中性。X射线晶体学分析表明,化合物1中的两个Ni(II)中心呈扭曲的八面体几何形状,并且两个SCN-基团的每个N原子桥接了两个金属中心。另一方面,化合物2具有中心对称的三核结构,其中两个扭曲的方形锥体末端Ni(II)中心通过苯氧杂桥与中央八面体Ni
Molecular and Electronic Structures of Dinuclear Iron Complexes Incorporating Strongly Electron-Donating Ligands: Implications for the Generation of the One- and Two-Electron Oxidized Forms
作者:Julia B. H. Strautmann、Carl-Georg Freiherr von Richthofen、Gabriele Heinze-Brückner、Serena DeBeer、Eberhard Bothe、Eckhard Bill、Thomas Weyhermüller、Anja Stammler、Hartmut Bögge、Thorsten Glaser
DOI:10.1021/ic101535y
日期:2011.1.3
complexes, with the possibility of fine-tuning the electronic structures by variation of the remotesubstituents. Molecular structures established in the solid (by single-crystal X-ray diffraction) and in solution (by X-ray absorption spectroscopy) show that the Fe ions are five-coordinate in a square-pyramidal coordination environment with the ligand adopting a trans-conformation. Spectroscopic and magnetic
配体(L t -Bu 2)2-,(L Me 2)2-和(L Cl 2)2-已用于合成双核Fe III配合物[L t -Bu 2 Fe(μ- O)FEL吨-Bu 2 ],[L我2的Fe(μ-O)FEL我2 ]和[L氯2的Fe(μ-O)FEL氯2 ]。强电子给体基团(叔选择(胺和酚盐)以增加配位的三价铁离子处的电子密度,从而促进络合物的氧化,并可能通过改变远程取代基来微调电子结构。在固体中(通过单晶X射线衍射)和在溶液中(通过X射线吸收光谱法)建立的分子结构表明,铁离子在方金字塔形配位环境中为五配位,且配体采用反式-构象。光谱和磁性表征确定了Fe III -O oxo和Fe III -O Ph的高度共价性质债券。酚盐的供体能力的变化(由于远端取代基的变化)通过Fe III -O oxo键的柔性电子给定得到补偿。光谱电化学表征表明,[L吨-Bu 2的Fe(μ-O)FEL吨-Bu 2 ]可在0.27可逆氧化和0
Highly cytotoxic vanadium(v) complexes of salan ligands; insights on the role of hydrolysis
作者:Lilia Reytman、Ori Braitbard、Edit Y. Tshuva
DOI:10.1039/c2dt11514j
日期:——
oxo complexes with tetradentate diaminebis(phenolato) “salan” ligands of the type LVO(OiPr) (L is salan) with different steric and electronic substitutions at the ortho and para positions to the binding phenolato moiety were synthesized and their hydrolytic stability and cytotoxicity were analyzed. With one exception bearing large steric groups, all complexes examined displayed marked cytotoxic activity
Cytotoxic Titanium Salan Complexes: Surprising Interaction of Salan and Alkoxy Ligands
作者:Timo A. Immel、Ulrich Groth、Thomas Huhn
DOI:10.1002/chem.200902312
日期:——
The synthesis, biochemical evaluation, and hydrolysis studies of a wide selection of alkyl‐ and halogen‐substitutedtitanium salan alkoxides are presented herein. A systematic change in the employed alkoxides revealed that both the bulk of the salan ligands and the steric demand of the labile ligands are of great importance for the obtained biological activity. Surprisingly, these two factors are not
Investigation of vanadium(<scp>iii</scp>) and vanadium(<scp>iv</scp>) compounds supported by the linear diaminebis(phenolate) ligands: correlation between structures and magnetic properties
(salans) L1–5 ligands (L1 = [MeNCH2CH2NMe(CH2-4-CMe2CH2CMe3-C6H3O)2]2−; L2 = [MeNCH2CH2NMe(CH2-4-CH3-C6H3O)2]2−; L3 = [MeNCH2CH2NMe(CH2-4-Cl-C6H3O)2]2−; L4 = MeNCH2CH2NMe[CH2-4,6-(CH3)2-C6H2O]2}2−; and L5 = MeNCH2CH2NMe[CH2-4,6-(Br)2-C6H2O]2}2−) and non-oxidovanadium(III) with L2,4 and acac ligands has been prepared and characterized by chemical and physical techniques. Reactions of [VO(acac)2] with ligand