Synthesis and Antibacterial Activity of Metal Complexes of Cephalothin

The interactions of cephalothin (Hcephalo) with transition metal(II) ions and imidazole have been investigated. The complexes [M(cephalo)Cl], (where M=Mn(II), Co(II), Ni(II), Pd(II)) and [M(cephalo)(Im)Cl] (where M=Ni(II), Cu(II), Zn(II), Im=Imidazole) were obtained and characterized by physicochemical and spectroscopic methods. The IR and the ¹H-NMR spectra of the complexes suggest that the cephalothin behaves as a monoanionic tridentate ligand. They have been screened for antibacterial activity against several bacteria, and the results are compared with the activity of cephalothin.     

三核过渡金属配合物在催化反应中的研究进展

多核过渡金属配合物作为一类广泛应用的均相催化剂,其设计灵感往往来自天然酶的多金属活性位点所发挥的重要作用.目前,三核金属配合物作为活化小分子的多金属催化剂受到了广泛的关注.为深入理解三核过渡金属配合物在催化反应中作用特点,对近年报道的代表性三核过渡金属配合物按金属中心进行分类,并对配体环境形成特点及催化应用进行综述.从金属中心出发,讨论了三核过渡金属配合物的几何结构和电子特征;从配体环境出发,总结了关联三个独立的金属位点的配位环境特征;在催化应用方面,重点综述了三核过渡金属配合物在涉及特定化学键活化反应的催化作用机制,最后对三核过渡金属配合物的催化应用前景进行展望.     

Heterometallic Trinuclear Complexes of Macrocyclic Oxamide: Synthesis,Crystal Structures,and Magnetic Properties

Two heterometallic trinuclear complexes of macrocyclic oxamide [Co(Ni L¹ )₂ L² (H₂O)] · 3H₂O ( 1 ) and [Mn(Ni L¹ )₂ L² (H₂O)] · 0.5CH₃OH · 1.5H₂O ( 2 ) (H₂ L¹ = 2,3‐dioxo‐5,6,14,15‐dibenzo‐1,4,8,12‐tetraazacyclopentadeca‐7,13‐diene, H₂ L² = 5‐sulfosalicylic acid) were synthesized and structurally characterized by elemental analysis, IR spectroscopy, and X‐ray diffraction. Single‐crystal X‐ray analyses reveal that both the complexes contain discrete neutral trinuclear [(Ni L¹ )₂M L² (H₂O)] (for 1 and 2 , M = Co, Mn, respectively) moieties. The structures of 1 and 2 have oxamido‐bridged trinuclear [M^IINi^II₂] units and consist of one‐dimensional chains formed by strong intermolecular hydrogen bonds. Furthermore, the magnetic properties of complex 1 were investigated and discussed in detail.     

Trinuclear Metal Complexes Based on 1,10-Phenanthroline Derivates as Catalysts for Cleavage of a RNA-Model Substrate

Two multidentate ligands 2,9-di[6'-(2″-hydroxyl-3″-methoxyphenyl)-n-2',5'-diazahexyl]-1,10-phenanthroline(LA)and 2,9-di(6'-α-phenol-n-2',5'-diazahexyl)-1,10-phenanthroline(LB)were synthesized and fully characterized.Protonation of the ligands and the stability of the complexes of the ligands with divalent metal ions were investigated.The trinuclear metal complexes [Cu(Ⅱ)and Zn(Ⅱ)] of the ligands were studied,as catalysts,for the transphosphorylation of the RNA-model substrate 2-hydroxypropyl-p-nitrophenyl phosphate(HPNP).The second-order rate constants of HPNP-hydrolysis catalyzed by M3L and M3LH-1 were obtained,which indicated that Zn3LBH-1 was the most efficient catalyst among them.The proposed mechanisms included the activation of the substrate via binding to the metal ions and intramolecular nucleophilic attack by the deprotonated C2-hydroxyl of HPNP.     

Heterometallic Trinuclear Ni2Zn and Ni2Mn Complexes of Macrocyclic Oxamide: Synthesis and Crystal Structures

Two novel heterometallic trinuclear complexes of macrocyclic oxamide [Mn(NiL)2(HBTC)H2O] (1) and [Zn(NiL)2(HBTC)H2O] (2) (NiL, H2L = 2,3-dioxo-5,6,14,15-dibenzo-1,4,8,12-tetraazacyclo-pentadeca-7,13-dien, H3BTC = 1,3,5-benzenetricarboxylic acid) have been solvothermally synthesized and structurally characterized by elemental analysis, IR spectroscopy and single-crystal X-ray diffraction. For 1, the crystals crystallize in the monoclinic system, space group P21/c with a = 11.3595(5), b = 23.1498(11), c = 17.2558(8) and =101.2530(10)°. For 2, the crystals crystallize in the monoclinic system, space group P21/c with a = 11.5214(8), b = 20.6566(14), c = 18.4126(13)  and = 92.6770(10)°. The structures of 1 and 2 have oxamido-bridged trinuclear [NiⅡ2MⅡ] units and consist of two-dimensional supramolecular architectures formed by strong O-H…O intermolecular hydrogen bonds.     

若干三核羧酸配合物的振动光谱及其与结构的某些相关规律

报导了通式为［Ｆｅ_２Ｍ（μ_３－Ｏ）（μ－Ｏ_２ＣＲ）_６·Ｌ_３］·ＸＨ_２Ｏ［其中Ｍ＝Ｍｎ（Ⅱ），Ｃｏ（Ⅱ），Ｎｉ（Ⅱ），Ｆｅ（Ⅲ）（这时骨架为阳离子）；Ｒ＝ＣＨ_３，Ｃ_２Ｈ_５；Ｌ＝Ｈ_２Ｏ，ｐｙ］的３类１１个配合物的振动光谱。在谱带经验归属及简正坐标分析计算的基础上，分别详细讨论了配体及骨架的振动光谱与结构的某些相关规律。这些规律具有一定的普遍性，因而有其理论和实际应用价值。     

不对称双Schiff碱三核配合物的合成和磁性

不对称双Schiff碱三核配合物的合成和磁性;不对称双Ｓｃｈｉｆｆ碱;三核配合物;磁性     

A Novel Biferrocene Trinuclear Complex with Cis-Configuration

Recently,organometallicmaterialshavebeenattractingagreatdealofattentioninthefieldofnonlinearoptics"'.Sandwich-typecompounds,likeferrocene,areexamplesoforganometallicsystemsofpotentialinterestbecausetheycontainaromaticcyclopentadienylringsinteractingw...     

Synthesis and Characterization of a Novel Macrocyclic vic‐Dioxime and Some of its Mono and Trinuclear Complexes

The (E, E)‐dioxime containing a dithia‐dioxa‐diaza macrocyclic moiety 5,6 : 11,12 : 17,18‐tribenzo‐2,3‐bis(hydroxyimino)‐1,4‐diaza‐7,16‐dithia‐10,12‐dioxacyclooctadecane ( H₂L ) has been synthesized in high yield by a 1 + 1 addition of cyanogendi‐N‐oxide with 2,3 : 8,9 : 14,15‐tribenzo‐1,16‐diamino‐4,13‐dithia‐7,10‐dioxahexadecane ( 3 ) which was obtained from condensation reaction with 2‐amino thiophenol and 1,2‐bis(2‐bromoethoxy)benzene, in dichloromethane at –10 °C. Two vic‐Dioxime ligands coordinate with Ni(II), Cu(II) and Co(III) through its hydroxyimino nitrogen donor atoms by the loss of the oxime protons. Homo and heterotrinuclear Cu^II₃ and Co^IIIPd^II₂ complexes of this ligand have been prepared; their two ligand molecules are connected via hydroxyimino or BF₂⁺‐bridging groups and two of the metal ions are coordinated by a diaza‐dithia mixed donor macrocyclic moiety. The macrocyclic ligand and its transition metal complexes have been characterized on the basis of ¹H‐, ¹³C‐NMR, IR and MS spectroscopy and elemental analysis data.     

Transition Metal Complexes with Organoazide Ligands: Synthesis,Structural Chemistry,and Reactivity

A drastically enhanced stability is observed for organoazides (RN₃) in the presence of Cu²⁺ or Pd²⁺ when the azido group is included in a ligand system chelating the transition metal ions. X-ray structure analysis of such complexes (the structure of a cyclohexaneazide palladium complex is depicted) confirms that the alkylated nitrogen atom of the N₃ moiety is coordinated to the transition metal center.     

过渡金属离子为模板的卟啉过渡金属配合物的合成研究

系统研究了以过渡金属离子为模板的卟啉配合物的合成方法,探讨了金属离子加入的时间、加入方式,溶剂各组分配比,反应温度,反应时间等因素对反应的影响,得到最佳工艺参数:金属盐的加入最好在加入芳香醛和吡咯10～15min后,反应混合液的温度降到90℃以下,加入醋酸盐;混合溶剂配比为(2～5)∶(1～4)∶1;反应温度为120～145℃;反应时间为40～80min。并且利用该方法合成了34种金属卟啉配合物。利用元素分析,UV-Vis,IR, ¹H NMR对金属卟啉配合物的结构进行了表征,利用TG-DTA研究了它们的热稳定性,利用EPR研究了它们的顺磁性。结果表明:该方法操作简便,产物易于分离、提纯,产率由原来两步合成法的10%～25%提高到35.1%～48%。     

多二茂铁基二氮杂己烷及其过渡金属配合物的合成

乙二胺与二茂铁甲醛或双二茂铁甲基氟硼酸盐反应，合成了１，６－二（二茂铁基）－２，５－二氮杂己烷和１，１，６，６－四（二茂铁基）－２，５－二氮己烷，它们与过渡金属（Ｆｅ＾２＋，Ｃｏ＾２＋，Ｎｉ＾２＋，Ｃｕ＾２＋，Ｚｎ＾２＋）盐在乙醇或乙醇－二氯甲烷中反应，是１４种过渡金属配合物，对这些化合物进行了表征，二种配体及其铜配合物用作复合固体推进剂的燃速调节剂时，基本不迁移，而燃速催化效率均超过辛基二茂铁。     

羊毛—过渡金属络合物的合成及其选择性催化氢化性能的研究

合成和初步表征了以天然高分子羊毛为载体的羊毛一钯单金属和羊毛－钯－铁双金属络合物催化剂；研究表明，在羊毛－钯络合物催化剂中，引入第二金属能极大地改进它的催化性能，提高其催化选择性，更有效的接近酶催化剂的特征．在常温常压下，以羊毛－钯－铁双金属络合物作催化剂，能顺利地使氯代硝基苯和氯代苯甲醛选择氢化成氯代苯胶和氯代苯甲醇．产率均为１００％，有效地抑制了氰取代基的氢解脱除，络合物催化剂中的钯／铁原子比极大地影响着该类氢化反应选择性，在氯代硝基苯和氯代苯甲醛的氢化反应中，最佳的钯／铁原子比分别为１：３和１５：１，这时反应的选择性均达到１００％，溶剂和温度对氢化反应速度均有一定的影响．     

Synthesis and Crystal Structure of the Novel Chiral o—Hydroxyphenyloxazoline Metal Complexes

1 INTRODUCTION Optically active oxazolines have been extensi- vely used as valuable chiral ligands for transition metals in asymmetric catalysis[1]. The design and syntheses of new chiral oxazoline ligands have inspired many scientists to work with great efforts during the recent years. Our interest has been focus- ed on the studies of enantioselective transition- metal catalysis of heterocyclic ligands. In the pre- sent work, we choose o-hydroxyphenyloxazoline ligand for it has a rigi…     

二苯基呋喃甲酰基吡唑啉酮及其金属配合物的合成与电化学行为

二苯基呋喃甲酰基吡唑啉酮及其金属配合物的合成与电化学行为;二苯基呋喃甲酰基吡唑啉酮; 配合物; 合成; 电化学     

2,4-二羟基-5-乙酰苯乙酮缩水杨酰肼单Schiff碱及其配合物的合成

以吡啶,DMF为溶剂,成功合成了未见文献报道的2,4-二羟基-5-乙酰苯乙酮缩水杨酰肼单Schiff碱(LH2)的过渡金属配合物[ML,M=Cu(Ⅱ),Zn(Ⅱ),Ni(Ⅱ)和Co(Ⅱ)],其结构经UV,1HNMR,IR,MS及元素分析表征。结果表明,Schiff碱是一种三齿配体,在配合物中溶剂分子参与了配位。     

两个线形三核配合物的晶体结构及性质

合成并表征了2个新的线性三核配合物[Co₂^ⅢCo^ⅡL₂（μ-OAc）₄]（1）和[Ni₃L₂（μ-OAc）₂（CH₃OH）₂]·2H₂O（2）,其配体L为2-羟基-1,3-丙二胺和5-氟水杨醛缩合的产物。配合物1与DNA的作用通过紫外-可见光谱、荧光光谱、粘度实验和电化学方法进行了研究。紫外-可见光谱的结果表明配合物1与DNA的结合常数为2.43×10⁵ L·mol^-1。荧光光谱的研究结果表明配合物1能取代溴化乙锭和DNA结合,其淬灭常数为4.92×10³ L·mol^-1。配合物1和2的变温磁学性质研究表明在2个配合物的三金属中心之间均存在反铁磁性耦合。     

两个线形三核配合物的晶体结构及性质

合成并表征了2个新的线性三核配合物[Co_2~ⅢCo~ⅡL_2(μ-OAc)_4](1)和[Ni_3L_2(μ-OAc)_2(CH_3OH)_2]·2H_2O(2),其配体L为2-羟基-1,3-丙二胺和5-氟水杨醛缩合的产物。配合物1与DNA的作用通过紫外-可见光谱、荧光光谱、粘度实验和电化学方法进行了研究。紫外-可见光谱的结果表明配合物1与DNA的结合常数为2.43×10~(5 )L·mol~(-1)。荧光光谱的研究结果表明配合物1能取代溴化乙锭和DNA结合,其淬灭常数为4.92×10~(3 )L·mol~(-1)。配合物1和2的变温磁学性质研究表明在2个配合物的三金属中心之间均存在反铁磁性耦合。     

系列同三核铬、锰、铁羧酸配合物的FAB-MS研究

进行了系列同三核羧酸配合物〔Ｍ３Ｏ（Ｏ２ＣＲ）６Ｐｙ３〕Ｘ（Ｍ＝Ｃｒ,Ｍｎ,Ｆｅ;Ｒ＝ＣＨ３,Ｃ２Ｈ５,Ｃ６Ｈ５;Ｘ＝Ｃｌ－,ＣｌＯ４－;Ｐｙ为吡啶）的快原子轰击质谱（ＦＡＢ－ＭＳ）研究。获得了包括配位吡啶在内的完整阳离子峰。在研究其断裂规律时,主要观察到４个系列碎片离子：Ⅰ．〔Ｍ３Ｏ（Ｏ２ＣＲ）ｎ〕＋,ｎ＝６～２;Ⅱ．〔Ｍ３Ｏ（Ｏ２ＣＲ）ｎＯ〕＋,ｎ＝５～１;Ⅲ．〔Ｍ２Ｏ（Ｏ２ＣＲ）ｎ〕＋,ｎ＝３～１;Ⅳ．〔Ｍ２（Ｏ２ＣＲ）ｎ〕＋,ｎ＝４～２。通过对该系列配合物质谱断裂过程的比较和分析,获得了配合物稳定性随金属离子及配体的变化如下：金属离子,Ｃｒ＞Ｍｎ＞Ｆｅ;桥配基,－ＣＨ３ＣＯ２＞－Ｃ２Ｈ５ＣＯ２＞－Ｃ６Ｈ５ＣＯ２;端配基,Ｐｙ＞Ｈ２Ｏ。本研究及先前的工作〔１,８〕还为某些三核铬,铁羧酸配合物在以乙炔加水或加氢为探针反应中存在活性物种：〔Ｃｒ３Ｏ（Ｏ２ＣＲ）３～４〕,〔Ｆｅ３Ｏ（Ｏ２ＣＲ）３〕和〔Ｆｅ３Ｏ－（Ｏ２ＣＲ）Ｏ〕～〔Ｆｅ３Ｏ４〕提供了佐证