Structure and Photosynthetic Mimicking of Bis（2,6—bis（benzimidazol—2—yl）pyridine）manganese（Ⅱ）

Mn(bzimpy)2(1)[bzimpy=2,6-bis(benzimidazol-2-yl)pyridine],a mononuclear manganese(Ⅱ）complex,was synthesized by the reaction of Mn(OOCMe)2 with bzimpy in absolute ethanol.The complex was structurally characterized by elemental analysis,cyclic voltammetry,and X-ray crystallography.In the complex,the manganese-nitrogen distances were different,and the geometry and the metal ion environment showed the distortion.The cyclic voltammetric measurements have been performed to assess its redox characteristics.The presence of oxidation wave at 0.62V and 0.081V vs.SCE or 0.8V and 1.0v vs.NHE suggested that this complex could catalyze the oxidation of water,therefore,simulate the water-oxidizing complex(WOC) of photosystem Ⅱ (PS Ⅱ).The measurements of photoreduction of 2,6-dichlorophenolindophenol (DCPIP),and oxygen evolution in the manganess-depleted and the comples 1-reconstituted PS Ⅱ preparations just support our conjecture.     

Synthesis,crystal structures,and properties of copper(II) complexes with 2,6-bis(benzimidazol-2-yl)pyridine

Three new mononuclear copper(II) complexes, [CuL(2-fca)(CH₃OH)]ClO₄?·?CH₃OH (1), [CuL(m-nba)(CH₃OH)]ClO₄ (2), and [CuL(pic)(ClO₄)]?·?CH₃OH (3), were synthesized and structurally characterized, where L is 2,6-bis(benzimidazol-2-yl)pyridine, while 2-fca, m-nba, and pic are the anions of 2-furoic acid, m-nitrobenzoic acid, and picolinic acid, respectively. All of them were characterized by elemental analysis, infrared, UV-Vis, and X-ray crystallography. In 1 and 2, the Cu(II) resides within a distorted square-pyramidal N₃O₂ coordination sphere with three nitrogens of L, one carboxylate oxygen, and one methanol. In 3, Cu(II) is coordinated with three nitrogens of L, one nitrogen and one oxygen of picolinate, and one oxygen of perchlorate in a distorted octahedral geometry. Two molecules of 1, 2, and 3 are interacted by intermolecular hydrogen-bonding interactions and strong π–π stacking interactions to form a dinuclear structural unit. The dinuclear units are further connected by H-bonds via perchlorate or lattice methanol to form a 1-D chain for 1 and 2-D network structures for 2 and 3. Hydrogen-bonding and π–π stacking interactions are important for the stabilization of the final supramolecular structures of the three complexes.     

Synthesis,crystal structure,and DNA-binding of a 3-D netlike supramolecular manganese picrate complex with 2,6-bis(benzimidazol-2-yl)pyridine

Manganese picrate with 2,6-bis(benzimidazol-2-yl)pyridine (L) has been prepared and characterized by elemental analysis, IR spectroscopy, and single-crystal X-ray diffraction. The complex crystallizes in the triclinic system, space group P–1 with a = 14.234(3) Å, b = 14.324(2) Å, c = 15.242(2) Å, α = 77.569(2)°, β = 63.350(3)°, γ = 82.130(2)°, and Z = 2. Interaction of the complex with calf-thymus DNA (CT-DNA) has been investigated with diverse spectroscopic techniques and viscosity measurements, and the binding constant is 1.76 × 10⁵ mol^?1. Results suggest that the complex bind to CT-DNA via intercalation.     

2,6-二(2-苯并咪唑基)吡啶与稀土苦味酸盐配合物的合成、晶体结构及荧光性质研究

合成了稀土苦味酸盐(pic)与配体2,6-二(2-苯并咪唑基)吡啶(L)的配合物,通过元素分析、红外光谱及电子光谱对配体及配合物进行了表征,并用X射线单晶衍射测定了配合物[CeL2(pic)2](pic)?(CH3OH)3的晶体结构.配合物属于三斜晶系,空间群为P-1,晶胞参数a=1.3795(3)nm,b=2.1292(5)nm,c=2.5651(6)nm,α=105.847(3)°,β=100.150(3)°,γ=107.893(3)°,Z=2,R=0.0519,wR=0.1255.晶体中一个不对称单元内有两个结晶学上独立的分子,这两个分子的构型基本相同,中心Ce3 均与两个三齿配位的配体及两个双齿配位的苦味酸根配位,配位数为10.中心Ce3 的配位多面体为变形双帽四方反棱柱,两个分子之间以π-π堆积连接,生成一个非中心对称的二聚体.整个晶体则是由这些二聚体以分子间氢键作用连接成三维网状超分子结构.室温下,在紫外光激发下Eu(III)配合物固体和溶液均表现出中心离子的特征荧光发射.     

Ruthenium monoterpyridine complexes with 2,6-bis(benzimidazol-2-yl)pyridine: Synthesis,spectral properties and structure

Ruthenium monoterpyridine complexes with the tridentate 2,6-bis(benzimidazol-2-yl)pyridine (LH₂), [Ru(trpy)(LH₂)]²⁺, [1]²⁺ and [Ru(trpy)(L²⁻)], 2 (trpy = 2,2′:6′,2″-terpyridine) have been synthesized. The complexes have been authenticated by elemental analyses, UV–Vis, FT-IR, ¹H NMR spectra and their single crystal X-ray structures. Complexes [1]²⁺ and 2 exhibit strong MLCT band near 475 and 509 nm, respectively, and are found to be very much dependent on solution pH. The successive pH dependent dissociations of the N–H protons of benzimidazole moiety of LH₂ in [1]²⁺ lead to the formation of 2. The proton induced inter-convertibility of [1]²⁺ and 2 has been monitored via UV–Vis spectroscopy and redox features. The two pK_a values, 5.75 and 7.70, for complex [1]²⁺ have been determined spectroscopically.     

微波作用下合成双(苯并咪唑-2-基)甲烷衍生物

在无溶剂、无催化剂存在条件下, 用微波促进5-取代-1H-苯并咪唑-2-乙酸乙酯和4-取代-1,2-邻苯二胺反应, 合成了取代双(苯并咪唑-2-基)甲烷衍生物, 产率均在80%以上. 产物结构经IR, ¹H NMR, MS等进行了表征.     

Synthesis and Crystal Structure of 2,6-Bis（benzimidazo（1,2-c）- quinazolin-6-yl）pyridine Tetrahydrate

The title compound, 2,6-bis（benzimidazo（1,2-c）quinazolin-6-yl）pyridine tetrahydrate, was synthesized by simple condensation of 2-（2-sminophenyl） benzimidazole with pyfidine- 2,6-dicarboxylic acid and characterized by elemental analysis, IR spectra and single-crystal X-ray diffraction. The crystal belongs to the monoclinic system, space group C2/c with a = 22.226（8）, b = 16.730（7）, c = 16.820（5）A, β = 115.796（13）°, V = 5631（4）A^3, C33H27NTO4, Mr = 585.62, Z = 8, Dc = 1.381 g/cm^3, λ（MoKα） = 0.71073 A, F（000） = 2448 and μ = 0.09 mm^-1. The structure was refined to the final R = 0.0730 and wR = 0.1573 for 6346 independent reflections （Rint = 0.0801） and 3384 observed reflections （I 〉 2σ（I））. In the crystal, the molecules are linked through intermolecular O-H…O and O-H…N hydrogen bonds. Intermolecular π-π interactions （with distances of about 3.45 A） are pronounced in the crystal structure.     

2,6-双(1-苄基-2-苯并咪唑基)吡啶的合成、晶体结构、光谱及抗氧化活性

合成了化合物2,6-双(1-苄基-2-苯并咪唑基)吡啶,通过元素分析、红外光谱、核磁共振氢谱和X-射线单晶衍射方法对其结构进行了表征.结构分析表明,该晶体属于单斜晶系,C2/c空间群,晶胞参数a=2.989 30(15) nm,b=1.093 74(5) nm,c=1.578 86(7) nm, β=103.555(5)o,V=5.018 32(42) nm3,Z=8,Dc=1.301 g/cm3,μ(Mo-Kα)=0.079 mm-1,F(000)=2 064,S=1.038,R1=0.046 0,w R2=0.127 9,化合物分子间存在的C—Hπ和苯环ππ堆积作用,使得其沿b轴方向形成了一维链状结构.通过紫外-可见吸收和荧光光谱研究了化合物的光谱性质及其对DPPH自由基的抗氧化活性.     

Synthesis and Structure of Copper(II) Nitrate Complexes with 2, 6‐Bis(pyrazolyl)pyridine

Three mononuclear copper(II) complexes of copper nitrate with 2, 6‐bis(pyrazol‐1‐yl)pyridine ( bPzPy ) and 2, 6‐bis(3′,5′‐dimethylpyrazol‐1‐yl)pyridine ( bdmPzPy ), [Cu(bPzPy)(NO₃)₂] ( 1 ), [Cu(bPzPy)(H₂O)(NO₃)₂] ( 2 ) and [Cu(bdmPzPy)(NO₃)₂] ( 3 ) were synthesized by the reaction of copper nitrate with the ligand in ethanol solution. The complexes have been characterized through analytical, spectroscopic and EPR measurements. Single crystal X‐ray structure analysis of complexes 1 and 2 revealed a five‐coordinate copper atom in 1 , whereas 2 contains a six‐coordinate (4+2) Cu^II ion with molecular units acting as supramolecular nodes. These neutral nodes are connected through O–H ··· O(nitrate) hydrogen bonds to give couples of parallel linear strips assembled in 1D‐chains in a zipper‐like motif.     

Syntheses,crystal structures,and DNA-binding properties of two nickel(II) complexes with 1,3-bis(benzimidazol-2-yl)-2-oxapropane derivatives

[Ni(obb)(DMF)₂(H₂O)]·(Pic)₂·0.5DMF (1) and [Ni(Etobb)₂]·(Pic)₂·2DMF (2) (obb = 1,3-bis(benzimidazol-2-yl)-2-oxapropane, Etobb = 1,3-bis(1-ethylbenzimidazol-2-yl)-2-oxapropane, Pic = picrate) have been synthesized and characterized by physicochemical and spectroscopic methods. The structures of both complexes have been determined by X-ray single-crystal diffraction. The coordination geometries of 1 and 2 can be described as distorted octahedra. The interaction of the nickel(II) complexes with calf thymus DNA was investigated by electronic absorption, fluorescence spectroscopy, and viscosity measurements. The experimental results suggest that 1 and 2 bind to DNA in an intercalation mode, and their binding affinity for DNA follows the order 1 > 2. DNA-binding behaviors can be attributed to the large coplanar aromatic rings in the V-shaped ligand and steric hindrance.     

Studies on the Synthesis,Crystal Structure and Quantum Chemistry of Di(o-cyanobenzyl)tin Bis(quinoline-2-carboxylate)

Di(o-cyanobenzyl)tin bis(quinoline-2-carboxylate)was synthesized by the reaction of tri(o-cyanobenzyl)tin chloride with quinoline-2-carboxylic acid.The molecular structure of the compound Was characterized by elemental analysis,IR,1H NMR and X-ray diffraction.Crystal data for the compound:triclinic,space group P1,a=0.80734(7),b=1.00681(9),c=1.04811(9)nm,α=81.7570(10),β=7.7240(10),γ=81.2850(10)°,V=0.77581(12)nm3,Z=1,Dc=1.488 g/cm3,μ(MoKa)=0.870 mm-1 and F(000)=350.1 The final R=0.0204 and wR=0.0530 for 2677 observed reflections with I＞2σ(I),and R=0.0208 and wR=0.0532 for all reflections.The molecular structure adopts a distorted octahedral geometry around the Sn atom.The title compound molecules are connected via hydrogen bonding interactions to form a 3D network structure.Quantum chemistry calculation study on the title compound has been performed by means of G98W package at the Lanl2dz basis set.The stability of the compound,orbital energies and some frontier molecular orbital composition characteristics have also been investigated.     

Studies on the Synthesis,Crystal Structure and Quantum Chemistry of Di（o-cyanobenzyl）tin Bis（quinoline-2-carboxylate）

Di（o-cyanobenzyl）tin bis（quinoline-2-carboxylate） was synthesized by the reaction of tri（o-cyanobenzyl）tin chloride with quinoline-2-carboxylic acid. The molecular structure of the compound was characterized by elemental analysis, IR, 1H NMR and X-ray diffraction. Crystal data for the compound： tficlinic, space group P1, a = 0.80734（7）, b = 1.00681（9）, c = 1.04811（9） nm, a = 81.7570（10）, β = 7.7240（10）,γ = 81.2850（10）°, V = 0.77581（12） nm3, Z = 1, Dc = 1.488 g/cm3, μ（MoKa） = 0.870 mm^-1 and F（000） = 350. The final R= 0.0204 and wR= 0.0530 for 2677 observed reflections with I 〉2σ（I）, and R = 0.0208 and wR = 0.0532 for all reflections. The molecular structure adopts a distorted octahedral geometry around the Sn atom. The title compound molecules are connected via hydrogen bonding interactions to form a 3D network structure. Quantum chemistry calculation study on the title compound has been performed by means of G98W package at the Lanl2dz basis set. The stability of the compound, orbital energies and some frontier molecular orbital composition characteristics have also been investigated.     

Synthesis and Structure of Bis[2,6-bis(2-pyridylamino)pyridinium] Tetrachlorocadmiumate(II)

1 INTRODUTION The d10 configuration of Cd(II) permits a wide variety of coordination numbers and geometries[1~3]. In recent years, one-, two- and three-dimensional infinite supramolecular coordination assemblies of Cd(II) have been the subject of great interest owing to their potential applications in catalysis, optical properties, clathration, etc[4~8]. In fabricating the coordination assemblies, organic ligands as well as inorganic anions have been observed to control the structural di…     

新型桥连双锌配合物的合成和结构

合成了二(2-苯并咪唑亚甲基)胺及其副产物[2，5-二(苯并咪唑亚甲基)环二肽 ]的混合配体与助Zn(Ⅱ)的双核超氧化物歧化酶模型化合物．进行了元素分析、紫 外和红外表征；对配合物采用X射线衍射方法测定了晶体结构，并采用G94W程序对 副产物[2，5—二(苯并咪唑亚甲基)环二肽]进行了量子化学计算．     

Synthesis,structure, and antioxidative properties of a copper(II) complex with 1,2-bis(benzimidazol-2-yl)ethane ligand

1,2-Bis(benzimidazol-2-yl)ethane (bbe) and its copper(II) complex, {[Cu(bbe)Br₂]₂}·2DMF ( 1 ), have been synthesized and characterized by elemental analysis, ultraviolet–visible, and infrared spectra. The single crystal structure analysis of 1 shows two crystallographically independent but chemically identical [Cu(bbe)Br₂] molecules. The coordination geometry of the copper atoms may best be described as a distorted tetrahedron (τ₄ = 0.740 for Cu1 and 0.696 for Cu2). The cyclic voltammogram of complex 1 represents quasi-reversible Cu²⁺/Cu⁺ pairs. in vitro antioxidant tests showed that complex 1 has significant antioxidant activity against superoxide and hydroxy radicals. Photoluminescence investigations showed that the fluorescence intensity of complex 1 is significantly weaker than that of the ligand. This may be due to the paramagnetic effect of divalent copper to cause quenching of fluorescence.     

Crystallographic report: Bis(acetato‐O,O′){4‐[N,N‐bis(2‐cyanoethyl)amino] pyridine}bis(methanol)cadmium(II), [Cd(C11H12N4) (CH3CO2)2(CH3OH)2]

The cadmium atom is coordinated in distorted pentagonal bipyramidal geometry by the pyridine‐nitrogen atom of the 4‐[N,N‐bis(2‐cyanoethyl)amino]pyridine ligand, two oxygen atoms of two methanol molecules and four oxygen atoms of two acetate groups. Copyright © 2005 John Wiley & Sons, Ltd.     

Synthesis,Crystal Structure and Catalytic Properties of a New 2D Nickel(II) Coordination Polymer Based on Flexible Bis(benzimidazole)

A new Ni(II) coordination polymer [Ni(L)2(SCN)2]n(L = 1,4-bis(benzimidazol-1-yl)butane) was synthesized hydrothermally and characterized by elemental analysis, IR spectroscopy and single-crystal X-ray diffraction. The title compound crystallizes in the monoclinic system, space group C2/c with a = 9.4760(3), b = 24.0408(8), c = 16.5871(5) A, β = 99.832(3)°, V = 3723.2(2) A3, Z = 4, Dc = 1.348 g/cm3, F(000) = 1576, the final R = 0.0486 and w R = 0.0936 for 2938 observed reflections with I 2σ(I) for the complex. Structural analysis shows that the coordination polymer possesses a 2D(4,4) layer structure which is composed of Ni(II) centers bridged by L ligand with two kinds of conformations and further assembled into a 3D supramolecular network via π-π stacking interactions. In addition, the fluorescence and catalytic properties, for the degradation of Congo red, of the complex were investigated.     

Crystallographic report: Bis{4‐[N,N‐bis(2‐cyanoethyl)amino]pyridine} dichlorozinc(II)

In (C₁₁H₁₂N₄)₂ZnCl₂, the zinc(II) center is coordinated by the pyridine nitrogen atoms of two 4‐[N,N‐bis(2‐cyanoethyl)amino]pyridine ligands and two chlorine atoms in a tetrahedral geometry. Copyright © 2004 John Wiley & Sons, Ltd.     

Synthesis and Structure of [Cu2（μ—NO2）（aepy）4]（ClO4）3 （aepy=2—（2—Aminoethyl）pyridine）

1 INTRODUCTION There has been great and considerable interest in the study of copper nitrite complexes because they are relevant to the study of copper-containing enzymes involved in the denitrification process[1]; in particular, copper-nitrite complexes are potentially relevant to the nitrite reductases[2] (the enzyme from Achromobacter Cycloclastes) which convert NO2－ to NO and/or N2O. Many attempts have been made to synthesize a variety of copper-nitrite complexes, in which the n…     

二(2-喹啉甲酸)二(邻氟苄基)锡配合物的合成、结构和量子化学研究

The novel di(o-fluorobenzyl)tin bis(2-quininate) has been synthesized. The crystal structures of the complex was determined by X-ray diffraction. The crystal belongs to triclinic space group P1 with a=0.770 8(2) nm, b=0.951 9(3) nm, c=1.108 4(3) nm, α=78.260(5)°, β=70.179(4)°, γ=68.594(4)°, V=0.709 4(4) nm³, Z=1, D_c=1.595 g·cm^-3, μ(Mo Kα)=9.57 cm^-1, F(000)=342, R₁=0.021 7, wR=0.056 6. The bond length Sn-C is 0.216 9(2) nm,The Sn-O is 0.217 64(15) nm, The Sn-N is 0.233 89(16) nm.This compound is monomeric, with six-coordinated tin atom in a distorted octahedron geometry. The study on title complex has been performed, with quantum chemistry calculation by means of G98W package and taking Lanl2dz basis set. The stabilities of the complex, the orbital energies and characteristics of some frontier molecular orbitals have been investigated. CCDC: 286107.