Reaction of Molybdenum Hexa-carbonyl with Mercapto-pyridine （PySH） or Mercapto-pyridine Oxide （PyS→O） and Crystal Structure of [Et4N][Mo2（PyS）3（CO）5]

Introduction Mercapto-pyridine, C5H4NS-(PyS), containing two active atoms, S and N, is a bidentate ligand, which may act as a 3-electron donor or a 5-electron donor and may be a bridging ligand to link two metal atoms to form polynuclear metal clusters or a chelating agent to coor-dinate to a metal atom by S and N atoms. So the mer-capto-pyridine is a very important reagent and its reac-tion with metal compound is very useful for simulating the active center in metal enzymes and syntheses …     

Synthesis and Crystal Structure of Bis（barbiturato） triwater Complex of Copper（Ⅱ）

1 INTRODUCTION A variety of transition metal complexes with barbiturates have been prepared owing to their important roles in clinical detection and identi- fication of drug[1～5]. They have the general formula of M(Ⅱ)(barb)2L2, where M is a transition metal (Co, Cr, Zn, Cu etc), barb the anion of a substituted barbituratic acid and L an organic base, usually pyridine. In these complexes, the donor atom in the barbiturate anion is a deprotonated nitrogen atom and, the coordination …     

Synthesis and Crystal Structure of a New Chain Coordination Polymer [Cu（inio）2（H2O）]∞ （Inio = Isonicotinic Acid N-Oxide）

1 INTRODUCTION With deep studies on the complex biology system and syntheses of new functional complexes, people have paid more and more attention to the polynuclear complexes. In the construction of one to three dimensional frameworks, multi-dentate ligands are usually used to bridge the metal centers to form polymeric structures[1, 2]. The isonicotinic acid N-oxide can function as a good mono-dentate ligand[3～8] through one oxygen atom from the group of -NO or carboxyl, and the dep…     

Extraction chromatographic study of aluminium(III) and mutual separation of aluminium(III), gallium(III), indium(III) and thallium(III) with N-n-octylaniline

A selective method has been developed for extraction chromatographic studies of aluminium(III) and its separation from several metal ions with a chromatographic column containing N-n-octylaniline (liquid anion exchanger) coated on silanized silica gel as a stationary phase. The aluminium(III) was quantitatively extracted with the 0.065 mol/L N-n-octylaninine from 0.013 to 0.05 mol/L sodium succinate at a flow rate of 1.0 mL/min. The extracted metal ion has been recovered by eluting with 25.0 mL of 0.05 mol/L hydrochloric acid and estimated spectrophotometrically with aurintricarboxylic acid. The effects of the acid concentration, the reagent concentration, the flow rate and the eluting agents have been investigated. The log-log plots of distribution coefficient (KdAl(III)) versus N-n-octylaniline concentrationin 0.005 and 0.007 mol/L sodium succinate gave theslopes 0.5 and 0.7 respectively and showed theprobable composition of theextracted species was 1:1 (metal to amine ratio) and the nature of extracted species is [RR''NH2+ Al succinate2-] org. .The extraction of aluminium(III) was carried out in the presence of various ions to ascertain the tolerance limit of individual ions. Aluminium(III) has been separated from multicomponent mixtures, pharmaceutical samples and synthetic mixtures corresponding to alloys. A scheme for mutual separation of aluminium(III), indium(III), gallium(III) and thallium(III) has been developed by using suitable masking agents. The method is fast, accurate and precise.     

Synthesis and Characterization of Yttrium Doped Nano-zirconia by a Cationic Surfactant-assisted Route

1INTRODUCTION Zirconia is a kind of metal oxide material with high melting point(2700℃),high boiling point,small thermal conductivity,large coefficient of ther-mal expansion,high temperature resistance,good abrasive resistance and favorable resistance to corrosion.Due to its both acid and alkaline surface centers,zirconia is an ideal catalytic material with acid group bi-functions[1].In addition,owing to the excellent ionic exchange property as well as the chemical and mechanical stabilit…     

一维链状化合物[Ag(L)]·H2O的合成、晶体结构和荧光性质

The title compound,[Ag(L)]·H2O,1,where HL=4-(isonicotinamido)benzoic acid,was synthesized in methanol solution and its crystal structure was determined by X-ray diffraction analysis.The crystal is of monoclinic.space group P21/c with a=0.571 8(8)nm,b=1.357 2(18)nm,c=1.5580(2)nm,β=91.090(2)°,V=1.2090(3)nm3,Z=4,Dc=2.009 g·cm-3,F(000)=722,Rint=0.042 9,R=0.027 1,wR=0.055 6.In complex 1,the Ag atoms are linearly coordinated by one O atom and one N atom of two ligand molecules.Each I- ligand in turn uses its one carboxylate group and one pyridinyl groups to connect two metal centers,then the one-dimensional (1D) chains is formed.On the other hand,the 1D chains are further connected by O1W-H1WB…O2 hydrogen bonds and Ag-O weak interactions to give a two-dimensional (2D) layer,finally,the 2D net extents to three-dimensional (3D) supramolecular framework by O1W-H1WB…O1 as well as N2-H2…O2 interactions.CCDC:762259.     

Enhanced confinement synthesis of atomically dispersed Fe-N-C catalyst from resin polymer for oxygen reduction

Due to larger atom utilization,unique electronic properties and unsaturated coordination,atomically dispersed non-precious metal catalysts with outstanding performances have received great attention in electrocatalysis.Considering the challenge of serious aggregation,rational synthesis of an atomic catalyst with good dispersion of atoms is paramount to the development of these catalysts.Herein,we report an enhanced confinement strategy to synthesize a catalyst comprised of atomically dispersed Fe supported on porous nitrogen-doped graphitic carbon from the novel and more cross-linkable Melamine-Glyoxal Resin.Densified isolated grid trapping,excessive melamine restricting,and nitrogen anchoring are strongly combined to ensure the final atomic-level dispersion of metal atoms.Experimental studies revealed enhanced kinetics of the obtained catalyst towards oxygen reduction reaction(ORR).This catalytic activity originates from the highly active surface with atomically dispersed iron sites as well as the multi-level three-dimensional structure with fast mass and electron transfer.The enhanced confinement strategy endows the resin-derived atomic catalyst with a great prospect to develop for commercialization in future.     

Kinetics and Mechanism of Oxidation of Lactic Acid by Dihydroxyditelluratoargentate（Ⅲ）in Alkaline Medium

The kinetics of the oxidation of lactic acid(Lac) by dihydroxyditelluratoargentate(Ⅲ）[abbreviated as DDA of Ag(Ⅲ）]anions was studied in an aqueous alkaline medium by conventional spectrophotometry in a temperature range of 25-40℃.The order of the redox reaction of lactic acid and DDA was found to be first-order.The rates increased with the increase in [OH^-]and decreased with the increase in [tellurate].No free radical was detected.In the view of this the dihydroxymonotelluratoargentate(Ⅲ）species(DMA) is assumed to be the active species.A plausible mechanism involving a two-electron transfer is proposed,and the rate equation derived from the mechanism can be used to explain all the experimenttal results.The activation parameters(25℃）and the rate constants of the rate-determining step along with the preequilibrium constants at different temperatures were evaluated.     

Synthesis and Magnetic Properties of Fe（Ⅱ） and Nd（Ⅲ） Complexes of Poly（N-2-thiazolylacrylamide）

N-2-Thiazolylacrylamide （NTA） was polymerized by a radical route to obtain the polymer in good yield. The polymer with a pendent heterocyclic group is soluble in common organic solvents, which allow to prepare the corresponding metal complexes with higher loads easily. FTIR, ^1H NMR, elemental analysis, and energy-dispersive X-Ray spectroscopy （EDX） were applied to characterize these materials. The magnetic behavior of Fe（Ⅱ） and Nd（Ⅲ） complexes of poly（N-2-thiazolylacrylamide） was examined by a PPMS-9T magnetometer, exhibiting the characteristics of a soft ferromagnet. It is found that the Nd（Ⅲ） complex has an extremely high relative saturation magnetization of 35 emu/g.     

Synthesis, Spectroscopic Properties and Crystal Structures of Dibenzyltin（IV） Dithiobenzoate and Chlorodibenzyltin（IV） Thiobenzoate

Two dibenzyltin(IV) complexes with thiobenzoate ligand, (PhCH2)2Sn(SOCPh)2 (1) and (PhCH2)2Sn(C1)SOCPh (2), have been synthesized by the reaction of dibenzyltin(IV) dichloride with thiobenzoic acid in the presence of organic base Et3N and characterized by IR, ^1H NMR spectroscopy and elemental analysis. Their crystal structures were determined by X-ray single crystal diffraction analysis. In the crystals of 1, the tin atom is six-coordinated in a distorted octahedron configuration. In the crystals of 2, the molecular packing in unit cell reveals that the two adjacent molecules are symmetrically linked to each other to form a dimer with intermolecular Sn…C1 distances of 0.3591 (2) nm and the tin atom is five-coordinated in a distorted trigonal bipyramid configuration.     

Synthesis and Crystal Structure of a Two-dimensional Silver（Ⅰ）-Iron（Ⅲ） Heteronuclear Coordination Polymer： {[Ag4Fe2（SCN）12（H2O）2] [（inaH）2（H2O）2]}n

The 2‐D heteronuclear coordination polymer {[Ag₄Fe2(SCN)₁₂(H₂O)₂] (inaH)₂(H₂O)₂}_n (1) (inaH is the abbreviation of protonated isonicotinic acid) with chemical formula C₂₄Ag₄Fe₂N₁₄O₈S₁₂ has been synthesized and characterized by single crystal X‐ray diffraction, elemental analysis and IR spectroscopy. The Ag₂S₂ rings connect two kinds of octahedral geometries of Fe(III) ions, [Fe(NCS)₆]^3– and Fe(H₂O)₂(NCS)₄]^? units with bridging thiocyanate ions leading to 2‐D [Ag₄Fe₂(SCN)₁₂(H₂O)₂^2– anion framework. Four kinds of rings including the unprecedented thirty‐two membered Ag₄Fe₄(SCN)₈ rings share comers or edges in the 2‐D anion layer structure. All thiocyanates coordinate to the metal ions according to the HSAB principle with N atoms binding to the Fe(III) ions and with S atoms binding to Ag(I) ions. Pronoated ina cations stabilize the layer structure as counter ions and hydrogen bonds were formed within the pronoated in a cations dimer and between the dimers and the lattice waters. Crystal data: M_r= 1560.44, triclinic, P1, a=0.76082(1) nm, b=0.9234 nm, c= 1.85611(4) nm, a= 103.0170(10)°, β=93.7780(10)°, y=97.4080(10)°, V= 1.25385(3) nm³, Z=1, μ(Mo Kα)=2.650 mm^?1, D_c,=2.067 g · cm^?3, F(000)=758, R₁=0.0412. wR₂=0.1003.     

A novel three‐dimensional AgI coordination polymer based on mixed naphthalene‐1,5‐disulfonate and aminoacetate ligands

The three‐dimensional coordination polymer poly[[bis(μ₃‐2‐aminoacetato)di‐μ‐aqua‐μ₃‐(naphthalene‐1,5‐disulfonato)‐hexasilver(I)] dihydrate], {[Ag₆(C₁₀H₆O₆S₂)(C₂H₄NO₂)₄(H₂O)₂]·2H₂O}_n, based on mixed naphthalene‐1,5‐disulfonate (L1) and 2‐aminoacetate (L2) ligands, contains two Ag^I centres (Ag1 and Ag4) in general positions, and another two (Ag2 and Ag3) on inversion centres. Ag1 is five‐coordinated by three O atoms from one L1 anion, one L2 anion and one water molecule, one N atom from one L2 anion and one Ag^I cation in a distorted trigonal–bipyramidal coordination geometry. Ag2 is surrounded by four O atoms from two L2 anions and two water molecules, and two Ag^I cations in a slightly octahedral coordination geometry. Ag3 is four‐coordinated by two O atoms from two L2 anions and two Ag^I cations in a slightly distorted square geometry, while Ag4 is also four‐coordinated by two O atoms from one L1 and one L2 ligand, one N atom from another L2 anion, and one Ag^I cation, exhibiting a distorted tetrahedral coordination geometry. In the crystal structure, there are two one‐dimensional chains nearly perpendicular to one another (interchain angle = 87.0°). The chains are connected by water molecules to give a two‐dimensional layer, and the layers are further bridged by L1 anions to generate a novel three‐dimensional framework. Moreover, hydrogen‐bonding interactions consolidate the network.     

A novel one‐dimensional double‐chain‐like ZnII coordination polymer: poly[bis(1‐benzyl‐1H‐imidazole‐κN3)tris(μ‐cyanido‐κ2C:N)(cyanido‐κC)disilver(I)zinc(II)]

One of most interesting systems of coordination polymers constructed from the first‐row transition metals is the porous Zn^II coordination polymer system, but the numbers of such polymers containing N‐donor linkers are still limited. The title double‐chain‐like Zn^II coordination polymer, [Ag₂Zn(CN)₄(C₁₀H₁₀N₂)₂]_n, presents a one‐dimensional linear coordination polymer structure in which Zn^II ions are linked by bridging anionic dicyanidoargentate(I) units along the crystallographic b axis and each Zn^II ion is additionally coordinated by a terminal dicyanidoargentate(I) unit and two terminal 1‐benzyl‐1H‐imidazole (BZI) ligands, giving a five‐coordinated Zn^II ion. Interestingly, there are strong intermolecular Ag^I…Ag^I interactions between terminal and bridging dicyanidoargentate(I) units and C—H…π interactions between the phenyl rings of BZI ligands of adjacent one‐dimensional linear chains, providing a one‐dimensional linear double‐chain‐like structure. The supramolecular three‐dimensional framework is stabilized by C—H…π interactions between the phenyl rings of BZI ligands and by Ag^I…Ag^I interactions between adjacent double chains. The photoluminescence properties have been studied.     

Luminescent Property of a Supramolecular Silver(I)‐Thiolate Complex Based on Secondary Ag‐S Interactions and Hydrogen Bonds

The supramolecular silver(I)‐thiolate complex [Ag(μ₂‐SC₄N₂H₄)₂(SCN)]_n has been prepared from the reaction of AgSCN and pyrimidine‐2‐thiol in DMF. X‐ray diffraction analysis shows that the supramolecular structure exhibits one‐dimensional chain through the secondary Ag‐S interactions and the chains are further linked by strong hydrogen bonds to form a three dimensional network. The luminescence effect from the silver‐centered state of S→Ag LMCT in solid state is different from that in solution due to the secondary Ag‐S interactions.     

A one‐dimensional silver(I) coordination polymer based on an asymmetric flexible N‐donor carboxylate ligand: catena‐poly[(μ3‐4‐{[(1‐phenyl‐1H‐tetrazol‐5‐yl)sulfanyl]methyl}benzoato‐κ3O:O′:N4)silver(I)]

The title compound, [Ag(C₁₅H₁₁N₄O₂S)]_n, was synthesized by the reaction of 4‐{[(1‐phenyl‐1H‐tetrazol‐5‐yl)sulfanyl]methyl}benzoic acid (Hptmba) with silver nitrate and triethylamine at room temperature. The asymmetric unit contains one crystallographically independent Ag^I cation and one ptmba⁻ ligand. Each Ag^I cation is tricoordinated by two carboxylate O atoms and one tetrazole N atom from three different ptmba⁻ ligands, displaying a distorted T‐shaped geometry. Three Ag^I cations are linked by tris‐monodentate bridging ptmba⁻ ligands to form a one‐dimensional double chain along the c axis, which is further consolidated by an intrachain π–π contact with an offset face‐to‐face distance of 4.176 (3) Å between the centroids of two adjacent aromatic rings in neighbouring benzoate groups. The one‐dimensional chains are linked into a three‐dimensional supramolecular framework by additional π–π interchain interactions, viz. of 3.753 (3) Å between two phenyl substituents of the tetrazole rings and of 4.326 (2) Å between a benzoate ring and a tetrazole ring. Thermogravimetric analysis and the fluorescence spectrum of the title compound reveal its good thermal stability and a strong green luminescence at room temperature.     

Synthese und Kristallstrukturen von heteronuklearen AgI/FeII‐Koordinationspolymeren: (Me3PhN)2[Ag2Fe(SCN)6], (Me3PhN)6[Ag6Fe3(ECN)18] (E = S,Se) und (Me3PhN)4[Ag2Fe(SCN)8]

The reaction of AgSCN with (Me₃PhN)₃[Fe(NCS)₆] in DMF yields two‐dimensional polymeric, heteronuclear complexes (Me₃PhN)₂[Ag₂Fe(SCN)₆] ( 1 ) and (Me₃PhN)₆[Ag₆Fe₃(SCN)₁₈] · CH₂Cl₂·DMF ( 2a ) with bridging SCN^? ligands, whereas additional (Me₃PhN)(SCN) leads to (Me₃PhN)₄[Ag₂Fe(SCN)₈] ( 3 ) with a one‐dimensional structure. The selenocyanato complex 2b , homologous to 2a , could also be prepared. Single crystal X‐ray structure determinations show, that the Ag⁺ ions in 1 and 2a are coordinated tetrahedrally by four S atoms, in 3 by one N and three S atoms of the bridging SCN^? ligands; six N atoms of the SCN^? or SeCN^? ligands bind to Fe²⁺ in an octahedral arrangement.     

A Novel Silver（Ⅰ）σ -Complex Supramolecular Polymer： [Ag2（o-HOPhCO2）2]n

The hydrothermal reactions of sodium o‐hydroxybenzoate with AgNO₃ yield a novel stable Ag(I) s?‐complex supramolecular polymer, [Ag₂(o‐HOPhCO₂)₂]_n. The structure of [Ag₂(o‐HOPhCO₂)₂] was solved by single crystal X‐ray diffraction analysis. It is monoclinic with space group P2Jc and unit cell parameters a=0.7394(2) nm, b= 0.8822(2) nm, c=1.0662(2) nm, β= 107.66(3)°, Z=4. The silver(I) atom is two‐coordinated by two carboxylic oxygen atoms of two o‐hydroxybenzoate ligands, and meanwhile, forms supramolecular interaction with one carbon atom of phenyl‐ring in the third o‐hydroxybenzoate group. The a‐form Ag…C supramolecular bond bridges [Ag₂(o‐HOPhCO₂)₂] units into an infinite 2D layered polymer [Ag₂(o‐HOPhCO₂)₂]_n. The coordination sphere of the silver atom is best described as a distorted T‐shaped geometry.     

A grid‐like two‐dimensional AgI coordination polymer: poly[[[μ3‐N′‐(4‐cyanobenzylidene)isonicotinohydrazide]silver(I)] perchlorate]

This study presents new coordinating modes of a Schiff base with three coordinating groups and an interesting two‐dimensional framework based on two types of constructing units. In the title compound, {[Ag(C₁₄H₁₀N₄O)]ClO₄}_n, the Ag^I ion is coordinated by three N atoms and one O atom from three different N′‐(4‐cyanobenzylidene)isonicotinohydrazide (L) ligands, forming a primary distorted square‐planar coordination geometry. Two ligands each bridge two metal centres through one carbonitrile N atom in a monodentate mode and the hydrazide N and O atoms in a bidentate mode to form a small centrosymmetric (2+2)‐Ag₂L₂ ring as a principal constructing unit. The pyridyl N atoms from four ligands in four of these small rings coordinate to Ag atoms in adjacent rings to form a large hexanuclear silver grid. A two‐dimensional framework of rectangular grids is constructed from these small rings and large grids. Two perchlorate anions are located in each large grid and are bound to the grid by N—H...O hydrogen bonding. Crosslinking between the layers is achieved through long Ag...O interactions between the perchlorate anions and Ag atoms in adjacent layers.     

A one‐dimensional silver(I) coordination polymer based on 5‐methyl‐1,3,4‐thiadiazol‐2‐amine and pyridine‐2,3‐dicarboxylate

The bifunctional pyridine‐2,3‐dicarboxylic acid (H₂pdc) ligand has one N atom and four O atoms, which could bind more than one Ag^I centre with diverse binding modes. A novel infinite one‐dimensional Ag^I coordination polymer, namely catena‐poly[[silver(I)‐(μ₂‐pyridine‐2,3‐dicarboxylato‐κ²N :O ³)‐silver(I)‐tris(μ₂‐5‐methyl‐1,3,4‐thiodiazol‐2‐amine‐κ²N :N ′)] monohydrate ethanol monosolvate], {[Ag₂(C₇H₃NO₄)(C₃H₅N₃S)₃]·H₂O·C₂H₅OH}_n , has been synthesized using H₂pdc and 5‐methyl‐1,3,4‐thiadiazol‐2‐amine (tda), and characterized by single‐crystal X‐ray diffraction. One Ag^I atom is located in a four‐coordinated AgN₄ tetrahedral geometry and the other Ag^I atom is in a tetrahedral AgN₃O geometry. A dinuclear Ag^I cluster formed by three tda ligands with a paddelwheel configuration is bridged by the dianionic pdc²⁻ ligand into a one‐dimensional coordination polymer. Interchain N—H…O hydrogen bonds extend the one‐dimensional chains into an undulating two‐dimensional sheet. The sheets are further packed into a three‐dimensional supramolecular framework by interchain N—H…O hydrogen bonds.     

Poly[μ2‐(N‐hydroxypyridine‐2‐carboxamidine)‐μ2‐nitrato‐silver(I)]

In the title complex, [Ag(NO₃)(C₆H₇N₃O)]_n or [Ag(NO₃)(pyaoxH₂)] (pyaoxH₂ is N‐hydroxypyridine‐2‐carboxamidine), the Ag⁺ ion is bridged by the pyaoxH₂ ligands and nitrate anions, giving rise to a two‐dimensional molecular structure. Each pyaoxH₂ ligand coordinates to two Ag⁺ ions using its pyridyl and carboxamidine N atoms, and the OH and the NH₂ groups are uncoordinated. Each nitrate anion uses two O atoms to coordinate to two Ag⁺ ions. The Ag...Ag separation via the pyaoxH₂ bridge is 2.869 (1) Å, markedly shorter than that of 6.452 (1) Åvia the nitrate bridge. The two‐dimensional structure is fishscale‐like, and can be described as pyaoxH₂‐bridged Ag₂ nodes that are further linked by nitrate anions. Hydrogen bonding between the amidine groups and the nitrate O atoms connects adjacent layers into a three‐dimensional network.