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991.
本文合成了一个新的含有4-对甲基苯基-3,5-二(2-吡啶基)-1,2,4-三氮唑配体(L)的锰(Ⅱ)配合物,[MnL2(NCS)2]。其结构由X射线晶体学,红外和电喷雾离子质谱表征。在晶体结构中, 锰原子有一反演中心并由2个三芳基三氮唑配体的4个氮原子和2个反式硫氰根的2个氮原子八面体配位。磁性测定表明在75~300 K的温度范围内该配合物是顺磁性的。  相似文献   
992.
1 INTRODUCTION The polymeric metal complexes with extended structures are of great interest because of their useful chemical or physical properties[1]. Due to the noticeable fact that the aromatic polycarboxylate can provide versatile coordination mode and the non-coplanar structure of the carboxylate groups and the benzene rings, a lot of efforts in this field have been particularly directed to the preparation of aromatic polycarboxylate (such as phthalate, tere- phthalate and isophthal…  相似文献   
993.
A novel Cd(Ⅱ) coordination polymer,{[Cd3(tzo)2(suc)(H2O)6]·(suc)}n (Htzo = 1,2,4-triazole,H2suc = succinic acid),has been synthesized from the reaction of aqueous solution of niques,and structurally characterized by X-ray analysis and spectral techniques.To the best of our knowledge,among the few documented triazole-cadmium coordination polymers,this complex presents a novel configuration.The deprotonated 1,2,4-triazole is in tridentate and succinate in bis-chelate modes to link the Cd(Ⅱ) centers,generating a 2-D grid-like network topology.Thermogravimetric analysis results show that the framework architecture is a stable porous material.The fluorescent emission has also been discussed.  相似文献   
994.
周健  刘星  李冬青  袁余洲  陈振锋  张勇 《合成化学》2006,14(5):476-479,509
利用水热法合成了标题化合物[Zn(H4FoPyS)2(H2O)4](NO3)2.3(H2O)(1,H4FoPyS为希夫碱吡啶-4-甲醛缩氨基脲),其结构经IR,元素分析,单晶X-射线衍射和热重分析表征。1的晶体结构属三斜晶系,空间群P,īa=9.6505(16),b=12.644(2),c=13.156(2),α=115.459(3)°,β=90.0290(10),°γ=111.792(3),V=1321.1(4)3,Dc=1.609 g.cm-3,Z=2,M r=647.84,μ=1.905 mm-1和F(000)=728,最终偏差因子分别为R1=0.0365和wR2=0.0878。1中Zn(Ⅱ)是六配位的稍变形八面体构型,其中2个吡啶氮原子和2个配位水分子占据赤道平面,另外2个配位水分子处于轴向位置。  相似文献   
995.
A new complex [Ni(phen)(mal)(H2O)2]·3H2O (phen = 1,10-phenanthroline,mal2-= malonic acid) has been synthesized by the reaction of nickel nitrate,phen and malonic acid.EA,IR spectra and X-ray single-crystal diffraction were carried out to determine the composition and crystal structure of the title complex.Crystal data:monoclinic system,space group P2/c,a =8.937(3),b = 12.163(5),c = 9.725(3)(A),β = 119.36°,C15H19N2O9Ni,Mr= 430.03,Z = 2,F(000) =446,V = 921.3 (A)3,Dc = 1.550 g/cm3,μ = 1.104 mm-1,-10≤h≤ 10,-12≤k≤ 14,-11 ≤l≤7,R =0.0261 and wR = 0.0609 for 4376 (Rint = 0.0203) independent reflections and 1631 observed ones (I> 2σ(I)).Ni(Ⅱ) exhibits an octahedral coordination geometry,with hydrogen bonds and π-π interactions stabilizing the whole structure.UV spectrum of the complex interacting with protamine DNA indicates that the title compound interacts with DNA via insertion mode with bonding constant Kb of 1.11 × 104.  相似文献   
996.
用紫外光谱观察到Ni2+离子与人或牛血清白蛋白相互作用有显著的滞后效应,表明Ni2+离子的结合可以诱导人或牛血清白蛋白发生从对Ni2+离子有较弱亲和力至较强亲和力构象态的缓慢变化(T-R转化);这一构象变化为试样的旋光能力随时间变化进一步证实;测得并讨论了这一构象变化的速度常数和活化参数;推测这一构象变化可能主要发生在蛋白质的IA亚区,并且很可能是一种促使IA亚区变得更加开放的"绞链式运动".  相似文献   
997.
A flexible double betaine 1,4-bis(pyridinil-4-carboxylato)-1,4-dimethylbenzene L has been used to generate two Cu(II)-containing metal complexes that exhibit different polymeric structures: [Cu(H2O)2 L]·2NO3 1 and [Cu(H2O)3 L]·2Cl·H2O 2. The crystal structures of 1 and 2 have been determined by single-crystal X-ray diffraction method. Crystal data for 1: triclinic, space group P 1, a = 5.253(2), b = 7.406(3), c = 14.792(5) , α = 84.195(5), β = 80.014(5), γ = 78.053(5)°, V = 553.2(3) 3, Z = 1, F(000) = 293, Dc = 1.717 g/cm3, the final R = 0.0385 and wR = 0.1079 for 1883 observed reflections (I > 2σ(I)); and those for 2: monoclinic, space group P21/c, a = 10.222(3), b = 25.287(7), c = 9.277(3) , β = 93.572(5)°, V = 2393.2(12) 3, Z = 4, F(000) = 1140, Dc = 1.540 g/cm3, the final R = 0.0472 and wR = 0.0956 for 3204 observed reflections (I >2σ(I)).  相似文献   
998.
利用3-氨丙基功能化的介孔SBA-15(APS-SBA-15)作为载体, 通过C—N共价键将8-羟基喹啉铜(Ⅱ)固定到APS-SBA-15孔道中, 制备了8-羟基喹啉铜(Ⅱ)功能化的SBA-15催化剂[Cu(Ⅱ)-Q-APS-SBA-15], 并将其用于以质量分数30%的过氧化氢为氧化剂的苯酚羟化反应中. 结果表明, Cu(Ⅱ)-Q-APS-SBA-15呈现出较高的苯酚转化率和苯二酚选择性.  相似文献   
999.
1 INTRODUCTION The Schiff bases derived from salicylaldehyde and 2-aminopyridine derivatives have been used as potentially terdentate ligands[1]. Yamada and Yam- anouchi have synthesized the type of ML2nH2O complexes (M = CoⅡ, NiⅡ, CuⅡ, ZnⅡ or PdⅡ)[  相似文献   
1000.
The structure of the title compound has been determined by X-ray crystallography. Each copper atom is chelated by two N-salicylidene-aniline anion ligands with Cu-O and Cu-N distances of 0.187 6(3) and 0.200 1(4) nm, respectively. The central copper(Ⅱ) is four-coordinated and in distorted square-planar environment. The phenyl rings with salicylidene moieties form a dihedral angle of 65.40°. There are C-H…π supramolecular interactions in the crystal structure. The title compound is also examined by elemental analysis, FT-IR, UV spectra and TG-DSC analysis. CCDC: 222315.  相似文献   
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