含混合多齿螯合配体双缺口立方烷型四核Mn配合物的合成、晶体结构与磁性研究

本文报道了一个含混合多齿螯合配体的四核Mn配合物Na₂[Mn₂^ⅢMn₂^Ⅱ(pdmH)₂(L)₂(N₃)₂]·2CH₃OH·2H₂O(1·2CH₃OH·2H₂O,pdmH₂为2,6-吡啶二甲醇,H₂L为2,6-吡啶二甲醇与2,2-二吡啶酮水合物的脱水物),并对其进行单晶结构分析、红外、元素分析和磁性研究。单晶结构分析表明,该化合物属于三斜晶系P1空间群,分子中2个Mn²⁺、2个Mn³⁺及6个来自pdmH-或L^2-配体的O原子构成1个双缺口立方烷结构。磁性研究表明Mn²⁺与Mn³⁺之间为弱的反铁磁性耦合作用(J₁=-0.89cm^-1,J₂=-1.13cm^-1),Mn³⁺离子之间为稍强的铁磁性耦合作用(J₃=3.20cm^-1),基态自旋值S=2,交流磁化率研究表明,在所测试条件下,其虚部没有表现出单分子磁体所具有的频率依赖现象。     

氰根桥连的FeⅢMnⅡ链中磁性作用的调控

基于三氰构筑单元合成了两个氰基桥联的Fe^ⅢMn^Ⅱ一维链, {[Fe(Tp)(CN)₃]₂[Mn(bib)]}·CH₃OH·2H₂O (1)和{[Fe(pzTp)(CN)₃]₂[Mn(bib)]}·3H₂O (2)。1和2中的双之字链通过刚性的双齿配体固定排列方式并连接成二维结构, 链内Fe^Ⅲ和Mn^Ⅱ之间的磁相互作用可以通过改变链中配体的位阻调控。     

基于多齿希夫碱配体的四核和十核锰簇合物的合成、结构和磁性

合成了一种具有{NO₄}给电子组成的多齿水杨醛希夫碱配体,3,5-二-叔丁基水杨醛-三(羟甲基)氨基甲烷(H₄L),并利用元素分析、红外光谱以及核磁共振氢谱表征其结构。Mn(ClO₄)₂或MnCl₂·4H₂O分别与该配体在溶液中反应生成了一个四核锰簇合物[Mn₄^Ⅲ(HL)₂(H₂L)₂(MeCN)₄](ClO₄)₂·2MeCN(1)和一个十核锰簇合物[Mn₆^ⅢMn₄^Ⅱ(bz)₁₀(L)₄(H₂O)₂]·10MeCN(2)。X-射线衍射分析表明化合物1的晶体结构空间群为三斜P1,而化合物2为正交Aba2。2~300K温度区间的磁性测量数据表明化合物2中存在反铁磁相互作用。     

基于二氰根铬的一系列氰根桥联CrⅢ-CuⅡ-CrⅢ三核配合物的合成、结构与磁性

基于一系列二氰根铬与[Cu(cyclam)](ClO₄)₂反应合成了3个氰根桥联Cr^Ⅲ-Cu^Ⅱ-Cr^Ⅲ三核配合物[Cu(cyclam)][Cr(bpmb)(CN)₂]₂·4H₂O(1)(cyclam=1,4,8,11-四氮杂环十四,bpmb^2-=1,2-二(2-吡啶甲酰胺基)-4-甲基苯),[Cu(cyclam)][Cr(bpdmb)(CN)₂]₂(2)(bpdmb^2-=1,2-二(2-吡啶甲酰胺基)-4,5-二甲基苯)和[Cu(cyclam)][Cr(bpClb)(CN)₂]₂·4H₂O(3)(bpClb^2-=1,2-二(2-吡啶甲酰胺基)-4-氯苯)。单晶衍射结果表明:3个化合物是结构类似的中性三核配合物,均含有氰根桥联的Cr(Ⅲ)-CN-Cu(Ⅱ)-NC-Cr(Ⅲ)连接;磁性研究表明:氰根桥在Cr^Ⅲ和Cu^Ⅱ离子间传递弱的铁磁耦合作用,基于自旋哈密顿算符Ĥ=-2J_CrCuŜ_Cu(Ŝ_Cr1+Ŝ_Cr2)拟合得到它们的磁耦合常数分别是J_CrCu=1.53(2) cm^-1(1),0.45(1) cm^-1(2)和0.73(2) cm^-1(3)。     

氰根桥连的FeⅢMnⅡ链中磁性作用的调控

基于三氰构筑单元合成了两个氰基桥联的Fe^Ⅲ-Mn^Ⅱ一维链,{[Fe(Tp)(CN)₃]₂[Mn(bib)]}·CH₃OH·2H₂O (1)和{[Fe(pzTp)(CN)₃]₂[Mn(bib)]}·3H₂O (2)。1和2中的双之字链通过刚性的双齿配体固定排列方式并连接成二维结构,链内Fe^Ⅲ和Mn^Ⅱ之间的磁相互作用可以通过改变链中配体的位阻调控。     

咪唑-芳香多羧酸金属有机骨架化合物的合成、结构及性质

以5-(1H-咪唑)异酞酸(H₂L)为配体,在水热条件下合成了3个金属有机框架化合物:[PrL(HL)(H₂O)₂]·H₂O(1),Er(H_0.5L)₂(2)和[CoL(H₂O)₂]·H₂O(3)。单晶X-射线衍射测试结果表明,3个化合物都属于单斜晶系,P2₁/c空间群。化合物1中,Pr³⁺为九配位,而化合物2和3中,Er³⁺和Co²⁺均为六配位。在镧系配合物1和2中,配体中氮原子未参与配位。1为2D折叠形结构,2为3D框架结构。在过渡金属配合物3中,氮原子与Co²⁺配位,这有助于形成平面二维结构。化合物1和3通过分子间π-π堆积,进一步形成3D结构。3个化合物均展现出较好的热稳定性。     

一例由多齿席夫碱构筑的Tb2配合物的结构、荧光性质及生物活性

使用多齿希夫碱配体 H₄L(H₄L=N'',N″-((1E,1''E)-(1,10-菲咯啉-2,9-二酰基)双(亚甲基)双(2-羟基苯甲酰肼))与 Tb(acac)₃·2H₂O反应(acac^-=乙酰丙酮根),通过溶剂热法,设计并合成了一例结构新颖的双核铽配合物[Tb₂(L)(H₂L)]·2CH₃OH·CH₃CN (1),并研究了该配合物的结构、荧光性质及生物活性。单晶X射线衍射分析表明该配合物主要含有2个Tb^Ⅲ离子和2个失去不同质子的配体离子(L^4-和H₂L^2-)。中心Tb1和Tb2离子都是九配位的,其几何构型呈现扭曲的呼啦圈形。固体荧光实验测试结果表明：该配合物在室温下表现出Tb^Ⅲ离子的荧光特征发射峰。生物活性研究表明,与配体H₄L和稀土离子相比较,配合物具有更强的抗菌活性。采用紫外可见光谱法、循环伏安法、凝胶电泳法和荧光光谱法研究了该配合物与小牛胸腺DNA之间的相互作用,结果表明配合物主要以插入作用的方式与小牛胸腺DNA结合。     

微调镝(Ⅲ)离子配位环境提升单离子磁体有效能垒

对于合成化学家来说,通过合成策略调控单离子磁体的磁动力学是一项艰巨的任务。我们以三（2-羟基亚苄基）三氨基胍配体（L）合成了2例单核Dy（Ⅲ）配合物[Dy（L）₂（H₂O）₂]ClO₄·2H₂O·2CH₃CN·CH₃OH（1）和[Dy（L）₂（H₂O）₂]CF₃SO₃·4H₂O·2CH₃OH（2）。对其结构和磁性研究表明,不同的抗衡阴离子对于配合物1和2的动态磁行为有显著影响。2个配合物中,Dy（Ⅲ）中心都具有三角形十二面体D_2d对称性,在零直流场下表现出单离子磁体的行为,其有效能垒分别为358 K（1）和309 K（2）。结构参数对比表明轴向位置的键长和键角微小变化对轴向配体场产生了显著的影响,而轴向配体场的微小变化导致了2个配合物交流磁性的差异。     

两个一维配位聚合物的合成、晶体结构、电化学及光学性质

合成了2个新的Robson大环配位聚合物{[Mn₂L¹(1,4-bix)₂](ClO₄)₂·5H₂O·DMF}_n(1)和{[Cu₂L²(1,4-bix)](ClO₄)₂}_n(2)(H₂L¹和H₂L²分别为1,3-丙二胺与2,6-二甲酰基-4-氟苯酚和2,6-二甲酰基-4-氯苯酚通过[2+2]缩合的产物)。2个配合物通过1,4-二(1,2,4-三唑-1-甲基)苯(1,4-bix)桥连大环单元形成一维链状结构。配合物的HOMO-LUMO能带间隙通过循环伏安法、紫外-可见漫反射光谱进行了测定,结果表明有较低的能带间隙。     

两个基于双(4-吡啶-4-苯基)胺的钴(Ⅱ)、锌(Ⅱ)配合物的合成和晶体结构

以双(4-吡啶-4-苯基)胺(BPPA)和4,4-(六氟)双(苯甲酸)(H₂hfipbb)或对苯二甲酸(p-H₂bdc)为配体,采用溶剂热法与M(NO₃)₂·6H₂O(M=Co、Zn)组装合成了2个新的配合物{[Co₂(BPPA)(hfipbb)₂·(H₂O)₃]·6H₂O}_n(1)、{[Zn₂(BPPA)₂(p-bdc)₂]·H₂O·DMF}_n(2),X射线单晶衍射测定结果表明:配合物1和2均为二维结构。配合物1具有新的拓扑结构。配合物2的二维结构又可以组成三维框架结构。配合物1为正交晶系,Pnna空间群,a=2.6409(2) nm,b=1.71578(13) nm,c=1.50411(11) nm,V=6.8154(9) nm³,Z=4,μ=0.571 mm^-1,F(000)=2592,D_c=1.245 g·cm^-3,M_r=1383.76,R₁=0.0666,ωR₂=0.2089(I>2σ(I));配合物2为单斜晶系,C2/c空间群,a=2.79670(9) nm,b=1.81482(6) nm,c=2.30313(7) nm,β=102.1360(10)°,V=11.4283(6) nm³,Z=8,μ=0.906 mm^-1,F(000)=4944,D_c=1.391 g·cm^-3,M_r=1196.85,R₁=0.0398,ωR₂=0.1064(I>2σ(I))。此外,热重分析表明配合物1和2均具有良好的热稳定性。     

Aminobis(phenolate)s of imidomolybdenum(VI) and -tungsten(VI)

The reactions of trans-[MoO(ONO^Me)Cl₂] 1 (ONO^Me = methylamino-N,N-bis(2-methylene-4,6-dimethylphenolate) dianion) and trans-[MoO(ONO^tBu)Cl₂] 2 (ONO^tBu = methylamino-N,N-bis(2-methylene-4-methyl-6-tert-butylphenolate) dianion) with PhNCO afforded new imido molybdenum complexes trans-[Mo(NPh)(ONO^Me)Cl₂] 3 and trans-[Mo(NPh)(ONO^tBu)Cl₂] 4, respectively. As analogous oxotungsten starting materials did not show similar reactivity, corresponding imido tungsten complexes were prepared by the reaction between [W(NPh)Cl₄] with aminobis(phenol)s. These reactions yielded cis- and trans-isomers of dichloro complexes [W(NPh)(ONO^Me)Cl₂] 5 and [W(NPh)(ONO^tBu)Cl₂] 6, respectively. The molecular structures of 4, cis-6 and trans-6 were verified by X-ray crystallography. Organosubstituted imido tungsten(VI) complex cis-[W(NPh)(ONO^tBu)Me₂] 7 was prepared by the transmetallation reaction of 6 (either cis or trans isomer) with methyl magnesium iodide.     

Synthesis of a photoswitchable azobenzene-functionalized tris(indazol-1-yl) borate ligand and its ruthenium(II) cyclopentadienide complex

In this paper, the design and synthesis of a new indazole bearing a photoisomerizable fragment at its 4-position are presented as well as the photoisomerization studies on both the indazole precursor and the final ruthenium model complex. It was obtained after five steps, the last one being the cleavage of the indazole protecting group. Reaction of 1 equiv of this functionalized indazole with 2 equiv of plain indazole and dibromophenylborane gave access to a mixture of four tripodal ligands of the tris(indazolyl)borate family. In a last step, complexation of this mixture with [RuCp(CH₃CN)₃]PF₆ yielded the corresponding ruthenium complexes from which the target ruthenium complex coordinated to a dissymmetric azobenzene-functionalized tripodal ligand was successfully isolated. Photoisomerization occured reversibly upon irradiation with UV light at 365 nm.     

Reactivity of Cyanide and Thiocyanate Towards the Nitrosyl Carbonyl [Co(CO)3(NO)]

The reaction of equimolar amounts of [Co(CO)₃(NO)] and [PPN]CN, PPN⁺ = (PPh₃)₂N⁺, in THF at room temperature resulted in ligand substitution of a carbonyl towards the cyanido ligand presumably affording the complex salt PPN[Co(CO)₂(NO)(CN)] as a reactive intermediate species which could not be isolated. Applying the synthetic protocol using the nitrosyl carbonyl in excess, the title reaction afforded unexpectedly the novel complex salt PPN[Co₂(μ-CN)(CO)₄(NO)₂] ( 1 ) in high yield. Because of many disorder phenomena in crystals of 1 the corresponding NBu₄⁺ salt of 1 has been prepared and the molecular structure of the dinuclear metal core in NnBu₄[Co₂(μ-CN)(CO)₄(NO)₂] ( 2 ) was determined by X-ray crystal diffraction in a more satisfactory manner. In contrast to the former result, the reaction of [PPN]SCN with [Co(CO)₃(NO)] yielded the mononuclear complex salt PPN[Co(CO)₂(NO)(SCN-κN)] ( 3 ) in good yield whose molecular structure in the solid was even determined and its composition additionally confirmed by spectroscopic means.     

Copper(I)-2-(2′-pyridyl)benzimidazole catalyzed N-arylation of indoles

CuI-2-(2′-pyridyl)benzimidazole catalyst system can serve efficiently to promote N-arylation of various indoles to afford the N-arylated indoles. The bidentate ligand, 2-(2′-pyridyl)benzimidazole was proved superior to monodentate nitrogen-based ligands and well-known bidentate ligands such as 2,2′-bipyridyl and 1,10-phenanthroline.     

新型聚合物-聚亚胺醚酮(PIEK)的合成与性能研究

以1,4-双-(4′卤苯酰基)苯和4′4-二氨基二苯醚为底物,加入钯催化剂Pd2(dba)3及其配体BINAP,通过Hartwig-Buchwald缩聚反应合成了新型高性能材料———聚亚胺醚酮(PIEK).PIEK的一般性能由DSC,TG等测定,研究表明:该聚合物表现出较高的玻璃化转变温度(Tg>200℃)、良好的热稳定性(TD>500℃)及良好的溶解性能.     

Cadmium(II), manganese(II) and zinc(II) compounds

Three new compounds, [Cd(μ ₃ -Hpdh)(μ₂-Cl)] _n (1), Mn(Hpdh)₂(H₂O)₂ (2) and Zn(Hpdh)₂ (H₂O)₂ (3) (H₂pdh =?pyridine-2,3-dicarbo-2,3-hydrazide), have been synthesized and characterized by elemental analysis, IR spectra, TG and single-crystal X-ray diffraction. Under hydrothermal conditions, H₂pdh is generated by an in situ acylation of H₂pda (H₂pda =?pyridine-2,3-dicarboxylic acid) with hydrazine hydrate. Complex 1 features a 2D layer structure constructed by a dinuclear Cd(II) building block. In complexes 2 and 3, hydrogen bonding interactions connect mononuclear structures into 3D supramolecular frameworks.     

Synthesis and Crystal Structure of an Indenylnickel(II) NHC Complex (Ind)NiBr(1,3-bisbenzylimidazol-2-ylidene)

1 INTRODUCTION During the past few decades, indene and its substituted derivatives (Ind) are of special interest in Group IVB complexes owing to their easy coordina- tion modification by substitution[1～7]. The Ind li- gands can be tuned spontaneously to coordinate to the center metal from η1 to η5 via relatively facile “ring slippage”, thus leading to better stabilization of transition states or reaction intermediates[8]. How- ever, their applications in Group 10 metal complexes ha…     

Chromium(III), manganese(II) and iron(III) complexes based on hydrazone Schiff-base and azide ligands: synthesis,crystal structure and antimicrobial activity

A tridentate NNO donor hydrazine Schiff base, HL, was obtained from condensation of pyridine 2-carbaldehyde and 4-hydroxy benzohydrazide. HL and azide ligands with Cr(III), Mn(II) and Fe(III) have been used to synthesize [Cr(L)(N₃)(OCH₃)]₂ (1), [Mn(HL)₂(N₃)₂] (2), and [Fe(L)(N₃)(OCH₃)]₂·H₂O (3). HL is quite diverse in its chelating ability and can be a neutral or monoanionic ligand as a tridentate unit. In this paper, we report structures showing different denticities of the ligand having different charges. The ligand 1–3 was characterized by elemental analysis, FT-IR, and UV–vis spectral studies and solid-state structures were determined by single-crystal X-ray diffraction analysis, revealing that 1 and 3 are binuclear, while 2 is mononuclear. The efficiencies of the ligand and the three complexes were evaluated for antimicrobial activity; MIC data revealed that HL 1–3 are not strongly active in comparison to standard drugs.     

Synthesis,Crystal Structure and Fluorescence of a Three-dimensional Cd(II) Coordination Polymer [Cd(μ_(1,3)- SCN~-)_2(μ-dmpo)]_n (dmpo = 3,5-Dimethylpyridine N-Oxide)

1 INTRODUCTION For a long time much research interest has been focused on coordination polymeric compounds[1] be- cause they may afford new materials with useful properties, such as catalytic activity, micro-porosity, electrical conductivity, non-linear optical activity, magnetic coupling behavior and so on[2]. Thiocya- nate anion, pyridine N-oxide and its derivatives be- long to very useful bridge ligands and many com- plexes[3～5] with one of them as bridge ligand exhibit special propert…