Three new zinc（Ⅱ） coordination polymers： Modulation of extended structures driven by assistant ligands

Three new complexes, [Zn（dtb）（4,4′-bipy）]·5H2O （1）, [Zn（dtb）（bpp）]·H2O （2） and [Zn（dtb）（phen）2]·CH3- CH2OH·H2O （3） （dtb = 5,5′-dithiobis（2-nitrobenzoic acid）, 4,4′-bipy = 4,4′-bipyridine, bpp = 1,3-bi（4-pyridyl） propane, phen = 1,10-phenanthroline）, have been constructed by dtb ligand and zinc salt in the presence of different assistant N-containing ligands under hydrothermal conditions. The structures of the complexes were established by single-crystal X-ray diffraction analysis. Although compounds 1 and 2 are both 2D networks, the cavities＇ forms and pitch of helix are different. The structure of compound 3 shows a 1D helical chain, and is extended by the supermolecule interactions into a 2D framework. These neutral polymeric complexes exhibit structural and dimensional diversity due to the different coordination modes of the flexible dtb ligand and the effect of assistant ligands.     

Development of Fe(III)-containing ether-functionalized imidazolium ionic liquids for aryl Grignard cross-coupling of alkyl halides

A series of Fe(Ⅲ)-containing imidazolium-based ionic liquids containing ether substituents,including[C3OMim][FeCl4](1,[C3OMim]=1-(2-methoxyethyl)-3-methylimidazolium),[C3OiPim][FeCl4](2,[C3OiPim]=1-isopropyl-3-(2-methoxyethyl)imidazolium),[C3OBim][FeCl4](3,[C3OBim]=1-butyl-3-(2-methoxyethyl)imidazolium),[(C3O)2im][FeCl4](4,[(C3O)2im]=1,3-bis(2-methoxyethyl)imidazolium),[C3OMim][FeBr4](5)and[(C3O)2im][FeBr4](6),were prepared and characterized by elemental analysis,Raman spectroscopy and electrospray ionization mass spectrometry.The catalytic performances of 1–6 and related Fe(III)-based catalysts in the cross-coupling of aryl Grignard reagents with alkyl halides bearing-hydrogens were studied,revealing that mono(ether)functionality improves the catalytic activity and that bis(ether)functionality improves the reusability.After simply decanting the product contained in the ethereal layer,complex 4,which containing bis(ether)-functionalized imidazolium cation,could be successfully recycled seven times.     

Adlayer structure of TCNQ molecules on Cu(111): Anin situ STM study

In situ electrochemical scanning tunneling microscopy (STM) was employed to examine tetracyano- quinodimethane (TCNQ) layer adsorbed on Cu(111) electrode surface in 0.1 mol/L HClO₄ solution. The TCNQ molecules are found to form highly-ordered long range adlayer with a (4×4) symmetry. Each TCNQ molecule is adsorbed on Cu(111) surface in flat-lying orientation. The molecules are preferentially aligned with their long axes in the [121] direction. A structural model is proposed for the adlayer.     

Approach to synthesis of novel chiral 3-chloro-2(5H)-furanone and its application in asymmetric reactions

The synthetic method of the novel chiral synthon, 5-l-menthyloxy-3-chloro-2-(5H)-furanone 5a and its application in asymmetric reactions were investigated. 5a is easily obtained in highly optical purity, and acts as a stable acceptor of Michael addition with oxygen nucleophiles in tandem double Michael addition / internal nucleophilic substitution to offer the spiro-cyclopropane derivative containing four stereogenic centers 8, which it is difficult to obtain by routine methods. The synthetic methods for 5a and 8 are reported in detail and the new compounds are identified on the basis of their analytical data and spectroscopic data, such as UV, IR,¹H NMR,¹³C NMR, MS and elementary analysis. The absolute configuration of the interesting spiro-cyclopropanes, spiro [1-chloro-4-(l-menthyloxy)-5-oxo-6-oxa-biscyclo[3.1.0]hexane-2,3′-(4′-/-menthyloxy-5′-l-menthyloxybutyrolactone)] 8 was established by X-ray crystallography. This result can provide important synthetic strategy in synthesis of some complex molecules containing spiro-cyclopropane skeleton with multiple chiral centers.     

Structural diversity and reactivity of d^10 metal- （4-pyridylthio）acetate system

The hydrothermal synthesis and crystal structures of four coordination polymers, namely, 2D [Zn（μ3-ta）（pytaH）]n （1）, 2D [Zn（μ3-pyta）Cl]n （2）, 1D [Cd（μ-pyta）2（H2O）]n （3）, and 3D [Cd（μ3-pyta）（μ-Cl）]n （4） （pyta = （4-pyridylthio）acetate, ta = thioglycolate）, are reported. They are based on （4-pyridylthio）acetate and its derived ligand. The ta^2- ligand present in 1 was generated from an in situ C（sp^2）-S bond cleavage of the pyta ligand. In these compounds, versatile intermolecular interactions, such as close S…S interactions and strong （O-H…O/N/S） or weak （C-H…O/S, C-H…Cl） hydrogen bonding interactions, play an important role in the formation of three-dimensional supramolecular networks in the solid state.     

叠氮桥联一维链状聚合物[Cu_2(N_3)_4(en)_2]_n的合成及结构和磁性的研究

由CuCl2、NaN3和乙二胺在水溶液中反应,合成了分子聚合物[Cu2(N3)4(en)2]n(1)(en=乙二胺),并通过X射线单晶衍射确定了其晶体结构.晶体结构属于单斜晶系,C2/c空间群,其晶胞参数为a=17.672(5)A°,b=6.397(4)A°,c=26.221(7)A°,β=100.089(5)°,Z=16.在配合物1中,Cu(1)和Cu(2)离子分别采取四配位的平面几何构型和变形的八面体几何构型,每个Cu(1)之间通过单个叠氮以1,3位方式桥联形成一维链状结构.磁性研究表明,在配合物1中,Cu(II)与Cu(II)离子之间表现为反铁磁相互作用.用哈密顿函数H=-2JSCuSFe对其χMT-T曲线进行了拟合,得到配合物1的朗日因子g=2.11,交换常数J=-0.87cm-1.     

4，4’－联吡啶桥联双核铜配合物的合成、ESR谱和磁性

由４，４’－联吡啶与β－二酮合铜（Ⅱ）配合物在乙醇中反应，合成了一种新的双核配合物Ｃｕ２（ＴＴＡ）４（４，４＇－ｂｉｐｙ）（ＴＴＡ为噻吩甲酰三氟丙酮，４，４’－ｂｉｐｙ为４，４’－联吡啶）．用元素分析和红外光谱对产物进行了表征．从电子自族共振谱得到该配合物的分子轨道系数和键参数．变温磁化率的数值表明，配合物的磁性遵从居里定律．还讨论了４，４’－联吡啶传递磁交换的性能．４，４’－联吡啶作桥基难以有效地传递磁交换作用．     

The synthesis of a new type of calix[4]arene with chiral pendant

Two new chiral calixarenes were synthesized by condensing 1,3-bis-chlorocarbomethyl-calix[4] arenes with (1S, 2S)-2-amino-1-(4-nitrophenyl)-1,3-propanediol, a by-product from antibiotic industry, and were characterized by¹H-NMR, MS-FAB, and elemental analysis. The¹H-NMR spectra show that those molecules assume a cone conformation in solution. Foundation item: Supported by the Zi-Qiang Science Foundation of Wuhan University Biography: He Yong-bing, (1945-), male, Professor, research direction: supramolecular chemistry.     

Synthesis of the chiral spiro-cyclopropane derivative and its crystal structure

The spiro[ l-bromo-4-/-mentholoxy-5-oxo-6-oxabicyclo[3. 1.0] hexane-2, 3'-(4'-ethoxy-5'-/-men-thyloxybutyrolactone)] 4 was synthesized via the tandem double Michael addition/internal nucleophilic substitution of chiral synthon 1, 5-/-menthyloxy- 3-bromo-2 (5H)-furanone, with nucleophilic ethanol. The two synthetic routes to compound 4 and its analytical data of structure are reported. The absolute configuration of 4 was determined by X-ray crystallography. These results provide a valuable strategy for synthesizing some biologically active molecules.     

Synthesis and characterization of novel bridged porphyrins

The reaction of 5-(4-hydroxyphenyl)-10,15,20-triphenyl porphyrin with 2,6-dibromomethylpyridine and 4,4‘-dicarboxyl-2,2‘-bipyridine respectively gave 2,6-bis-[5,10,15-triphenyl-20-( 4-phenoxymethyl )-porphyrin-yl]-pyridine(3) and 4, 4‘-di-[5,10,15-triphenyl-20-( p-phenoxycarbonyl)-porphyrin-yl]-2,2‘-bipyridine (4). 5-[4-(4‘- Bromobutoxy) phenyl]-10, 15, 20-triphenyl porphyrin reacted with 2,6-dihydroxymethyl pyridine to give 2,6-bis-[5,10,15-triphenyl- 20-(4-(p-phenoxy)-butoxymethyl)-porphyrin-yl]-pyridine(5). Those new compounds have been identified by ^1H NMR, IR, MS and UV-visible spectra, and elemental analysis.     

基于{Cr（OH）6Mo6O18）^3-多酸阴离子为配体的过渡金属离子配合物的合成及结构表征

以β-Anderson型{Cr（OH）6Mo6O18}^3-多酸阴离子为配体,质子化的4,4’-bpy为模板,利用电荷平衡阳离子,在水热条件下,合成了三种过渡金属Mn（Ⅱ）、Co（^3-）和Ni（^3-）的配合物：[4,4’-bpyH2]2[-Mn{Cr（OH）6Mo6O18}2]1、[4,4＇-bpyH][-Co（H2O）2{Cr（OH）6Mo6O18）]·4H2O2和[4,4’-bpyH][-Ni（H2O）2{Cr（OH）6Mo6O18}]·4H2O3．通过元素分析、单晶X射线分析、红外表征、热重分析和X射线粉末衍射等技术确定了化合物的组成和结构．在配合物1中,{Cr（OH）eMo6O18}^3-多酸阴离子作为六齿配体,Mn（Ⅱ）采用八面体配位方式,形成一维带状结构．配合物2和3互为异质同构体,{Cr（OH）6Mo6O18}^3-多酸阴离子作为四齿配体,Co（Ⅱ）或Ni（Ⅱ）采用八面体配位方式,形成二维层状结构,[4,4’-bpyH]＋填充在层间．     

Measurement of the absorption spectrum of H2O+ in the visible region

Together with the 74 lines belonging to (0,9,0)- (0,0,0) band, the high-resolution absorption spectrum of H₂O⁺ A²A₁-X²B₁ system was observed in the visible region of 16680 — 17300 cm^-1 using optical heterodyne magnetic rotation enhanced velocity modulation spectroscopy for the first time, which verifies the high sensitivity and high signal to noise ratio (S/N) of this technique.     

3，15-聚{7，11，18，21-四氧杂三螺[5．2．2．5．2．2]二十一烷}化合物的合成及^1H-NMR谱特征

本文将4,4＇-二环己二酮单缩酮与季戊四醇反应,分别制得化合物3,15-双{8-（1,4-二氧杂螺[4．5]癸烷基）}-7,11,18,21-四氧杂三螺[5．2．2．5．2．2]二十一烷（1）和3,15-聚{7,11,18,21-四氧杂三螺[5．2．2．5．2．2]二十一烷}（2）,对其^1H—NMR的特征进行了讨论．发现三螺环中（B,C）原季戊四醇中的cH：不裂分,是个单峰;而A、D环上的CH2（H1,H5,H13,H17）受手性轴的影响而裂分成多重峰（如无手性轴的影响应为三峰）．表明手性轴对手性的影响主要集中在轴的外侧,对中心影响较小．所获结论对不对称合成中进行手性催化剂和手性固定相的设计具有理论意义．     

手性配合物[Mn（csal-R,R-chxn）]Cl的CD光谱和不对称催化作用

以5-氯-水杨醛双缩（1R,2R）-环己二胺（CSA-DMC）为原料制备了手性[Mn（csal-R,R-chxn）]Cl配合物,测定了手性配体CSA-DMC的荧光光谱,研究了手性配合物[Mn（csal-R,R-chxn）]Cl的CD光谱及催化苯乙烯不对称环氧化反应的催化性能.结果表明：手性配体CSA-DMC的荧光发射峰处于517 nm;利用激子裂分方法和d-d跃迁关联法推测了手性席夫碱配合物[Mn（csal-R,R-chxn）]Cl绝对构型为（R）Δλ构型;最适宜反应条件下,催化苯乙烯的不对称环氧化反应的转化率为74.9%,催化剂选择性为67.6%,对映体过量百分率（e.e.）为12.3%     

Molecular simulation study of the binding mechanism of [α-PTi<Subscript>2</Subscript>W<Subscript>10</Subscript>O<Subscript>40</Subscript>]<Superscript>7−</Superscript> for its promising broad-spectrum inhibitory activity to FluV-A neuraminidase

Polyoxometalate (POM) has promising antiviral activities. It shows broad-spectrum inhibiting ability, high efficiency, and low tox-icity. Experimental assays show that titanium containing polyoxotungstates have anti-influenza-virus activity. In this paper, the bind-ing mechanisms of five isomers of di-Ti-substituted polyoxotungstate, [α-1,2-PTi₂W₁₀O₄₀]^7– (α-1,2), [α-1,6-PTi₂W₁₀O₄₀]^7– (α-1,6), [α-1,5-PTi₂W₁₀O₄₀]^7– (α-1,5), [α-1,4-PTi₂W₁₀O₄₀]^7– (α-1,4) and [α-1,11-PTi₂W₁₀O₄₀]^7– (α-1,11), to five subtypes of influenza virus A neuraminidase (FluV-A NA) were investigated in the context of aqueous solution by using molecular docking and molecular dynamics studies. The results show that the isomer α-1,2 is superior to other isomers as a potential inhibitor to neuraminidase. The positively charged arginine residues around the active site of NA could be induced by negatively charged POM to adapt themselves and could form salt bridge interactions and hydrogen bond interactions with POM. The binding free energies of POM/NA complexes range from –5.36 to –8.31 kcal mol^–1. The electrostatic interactions are found to be the driving force during the binding process of POM to NA. The conformational analysis shows that POM tends to bind primarily with N1 and N8 at the edge of the active pocket, which causes the conformational change of the pincers structure comprising residue 347 and loop 150. Whereas, the active pockets of N2, N9 and N4 are found to be more spacious, which allows POM to enter into the active pockets directly and anchor there firmly. This study shows that negatively charged ligand as POM could induce the reorganization of the active site of NA and highlights POM as a promising inhibitor to NA despite the ever increasing mutants of NA.     

A practical process for the synthesis of translocator protein 18kDa imidazopyridine ligand

In this article, an effective feasible method to synthesize translocator protein 18kDa （TSPO） imidazopyridine ligand 7 is discussed. A new procedure for the synthesis of the key intermediate 17 has been developed in four steps （condensation, diazo reaction, hydrolysis, amidation） from 2-aminopyridine 18. The overall yield was increased from 18% to 31.6%. One of the key steps is using activated copper powder as a catalyst in several cycles. Finally, reduction of 17 with Zn dust completed the synthesis of TSPO imidazopyridine ligand 7 in 86% yield.     

Ionic iron（III） complex of aryloxo-linked bis（imidazolium） cations： efficient and recyclable catalyst for aryl Grignard cross-coupling of alkyl chlorides

A novel phenol-linked bis（imidazolium） salt, H3LCl2 （L = O-4-C（CH3）3-C6H2-2,6-di[CH2{C（NCHCH- NAr）}]2, Ar = 2,6-diisopropylphenyl, 1）, was designed and used to prepare an ionic iron（III） complex [H2L][FeCl4] （2）. Complex 2 was a highly efficient catalyst for aryl Grignard cross-coupling of alkyl chlorides bearing β-hydrogens. Furthermore, complex 2 was reusable and could be reused in at least eight times without significant loss in catalytic activity.     

螺环[2,3]己烷氢解反应机理的理论研究

在ＨＦ／６－３１Ｇ＊＊水平上（并用ＭＰ２法进行了相关能校正）,应用从头算子分子轨道法和能量梯度技术,研究了螺环〔２,３〕己烷氢解反应的机理。结果表明,该反应主要的２个途径为：（１）螺环〔２,３〕己烷氢解经四元环过渡态生成乙基环丁烷;（２）螺环〔２,３〕己烷氢解经四元环过渡生成生成１,１－二甲基环丁烷。计算结果２个途径活化能均过大,表明在催化剂条件下,反应难以进行。     

Use of ionic liquid in leaching process of brass wastes for copper and zinc recovery

Brass ash from the industrial brass manufacturer in Turkey was leached using the solutions of ionic liquid (IL) 1-butyl-3-methyl-imidazolium hydrogen sulfate ([bmim]HSO₄) at ambient pressure in the presence of hydrogen peroxide (H₂O₂) and potassium peroxymonosulfate (oxone) as the oxidants. Parameters affecting leaching efficiency, such as dissolution time, IL concentration, and oxidizing agent addition, were investigated. The results show that [bmim]HSO₄ is an efficient IL for the brass ash leaching, providing the dissolution efficiencies of 99% for Zn and 24.82% for Cu at a concentration of 50vol% [bmim]HSO₄ in the aqueous solution without any oxidant. However, more than 99% of zinc and 82% of copper are leached by the addition of 50vol% H₂O₂ to the [bmim]HSO₄ solution. Nevertheless, the oxone does not show the promising oxidant behavior in leaching using [bmim]HSO₄.     

A novel self-promoted Morita-Baylis-Hillman-like dimerization

While stable in CH₂Cl₂, hexane or THF, in the presence of MeOH, self-promoted dimerization of the triarylphosphine-alkene 1, a ligand for Pd-catalyzed reactions, produced an unusual racemic bis(phosphine) 2 in high yield. The reaction of 2 with Pd(dba)₂, followed by oxidative addition of p-IC₆H₄NO₂, yielded a trans-chelated Pd(II) aryl iodide complex.