Preparation and Identification of a New [Cr2(NTA)2(μ-OH2)]·2H2O Complex

[Cr₂(NTA)₂(μ-OH₂)]·2H₂O is prepared by heating nitrilotriacetic acid (H₃NTA) with an aqueous suspension of freshly precipitated Cr₂O₃·nH₂O. Elemental analysis, IR spectra, UV/vis spectra, X-ray diffraction, thermogravimetric analysis, mass spectra and magnetic susceptibility measurements suggest the existence of a Cr-Cr bond. One of the three water molecules acts as a bridging ligand (μ-H₂O) while the other two are waters of crystallization.     

Preparation and Chemical and Biological Studies of the Novel Complex μ-1,4,5-triphenyl-1,3,4-triazole-2-thiolate-bis[dichlorotriethylphosphineplatinum(II)]a

The mesoionic compound, 1,4,5-triazole-2-thiolate, is a versatile ligand, capable of binding metal centres in different ways. The present study shows how it reacts with the bridging platinum(II) complex μ-dichlorobis[(chlorotriethylphosphineplatinum(II)], [Pt₂(PEt₃)₂Cl₄], originating a bimetallic complex. Both the sulphur atom and nitrogen 3 behave as basic sites, coordinating different platinum centres. An interesting isomerization process, shown by ³¹P{¹H} n.m.r. spectroscopy, occurs at the S-bonded platinum moiety, resulting in a fluxional behaviour of the complex. It is also shown to target CT-DNA with moderate binding affinity.To the memory of Dr. Wagner M. Teles (1971–2004).     

Convenient Preparation of a Cyclopropanation Reagent: α-Siloxymethyliron Complex

A convenient preparation of α-siloxymethyliron complex (7) was developed from commercially available s-trioxane and/or paraformaldehyde. For synthetic utility, iron methylidene complex (8) was generated in situ from the α-siloxymethyliron complex (7) and cyclopropanes (10) by treatment with alkenes.     

Preparation and Catalytic Properties of Polymer Supported Dendritic Metal Complex

Polymer supported materials are extensively used as oxidizing agent, reducing agent catalysts, photosensitizers ion exchange resins and agriculturally and pharmacologically active agents1. The application of polymer metal complexes has been widely investigated2. The polymer supported complex undergoes swelling in a suitable solvent medium and provides enough surface area in carrying out electron transfer reactions, which clearly emphasizes the influence of a polymer network in heterogeneous ca…     

Preparation,Crystal Structure and Properties of a Pentametallic 3-Ferrocenyl-2-crotonic acid-Bridged Copper(II) Complex

IntroductionDimericcopper(II)carboxylatescontainingavarietyofoxygenandnitrogen donorligandshavebeenextensivelyinvestigatedandtheirpreparations ,magneticandspectralpropertieshavebeenreviewed .1 5Differentkindsofcopper(II)carboxylateadductshavebeensynthesizedandalsodinuclearcopper(II)complexeshavebeenearlystud iedasusefulmodelstoestablishmagneto structuralcorre lationsforspinexchangebetweenmetalions .Inparticu lar,theoccurrenceofdicopperionsattheactivesiteofthevariousformsoftheoxygencarrierpro…     

Preparation, Crystal Structure and Properties of a Pentametallic 3-Ferrocenyl-2-crotonic acid-Bridged Copper（Ⅱ） Complex

The synthesis and characterization of the copper (II) complex [Cu₂(OOCCH = C(CH₃)Fc)₃(phen)₂]CIO₄ · 2H₂O (1) are reported. The structure of the complex was determined by single‐crystal X‐ray analysis. The compound crystallizes in the monoclinic system, space group Pc, with Z =2, a = 1.2799(4) nm, b =0.9969 (4) nm, c = 2.5228 nm, and β = 91.576 (1) °. The cationic part of 1 indicates a penametallic core in which three 3‐ferrocenyl‐2‐crotonic acid salt (FCA) groups act as (O, O') bridging ligands between two copper (II) ions with a square‐pyramidal environment. Cyclic voltammetric experiments in acetonitrile have been performed mainly to examine the Fe(II) → Fe(III) one‐electron oxidation in FCA and its complex. The variable‐temperature magnetic susceptibility measurements revealed very weak intramolecular anti‐ferromagnetic coupling. Fitting parameters are 2J = ‐0.2 cm^?1, g = 2.114, and θ = 0K.     

Synthesis and Crystal Structure of Bis-(2,2'''' bipyridyl)-2-pyrimidinethiolate-Ni(Ⅱ) Complex

1 INTRODUCTION The design of metal complexes of bipyridine is one of the most highlighting topics in molecular materials with specific optical, electronic and mag- netic properties. What studied and well-documented most widely are those of the d6 metal polypyridines, and so are the d8 and d10 metal complexes with rich luminescence behaviour[1] very recently, which can be beneficial to the design of unique functional ma- terials. Currently our interest is to design lumine- scent heteronuc…     

Hydrothermal Preparation and Photophysical Properties of a Ni(Ⅱ) Complex Containing Quinoline Derivative and Phen Ligands

A novel nickel complex[Ni_2L_2Phen_3]·3H_2O (HL=3-hydroxy-2-methylquioline-4-carboxylic acid)has been synthesized by a hydrothermal approach and is structurally determined by single-crystal X-ray diffraction.The title complex crystallizes in triclinic space group ■.Crystal data for the title complex:C_(58)H_(44)N_8Ni_2O_9,M_r=1108.35,a=11.8648(4),b=12.7369(4),c=17.0728(5)?,α=97.694(3),β=96.702(2),γ=99.566(3)°,V=2495.66(14)?~3,Z=2,T=293(2) K,D_c=1.475 g/cm~3,μ(Mo Kα)=0.824 mm~(–1),F(000)=1140,R=0.0757,w R=0.2129 and GOF=1.017.The nickel ions are surrounded by five oxygen and six nitrogen atoms to yield two slightly distorted octahedral geometries.Solid-state photoluminescence spectrum reveals that it shows blue purple emission.Solid-state UV/Vis diffuse reflectance spectroscopy exhibits that it has an optical band gap of 1.702 e V.     

Synthesis, Structure and Properties of a Copper Complex Cu2(μ-PhCOO)2(μ-CH3COO)2(CH3OH)2

The title complex Cu2(μ-PhCOO)2(μ-CH3COO)2(CH3OH)2 1(C20H24Cu2O10, Mr=structure was determined by X-ray diffraction method. Complex 1 belongs to orthorhombic, space group Pbca with a = 13.083(6), b = 8.078(4), c = 21.566(2)(A), V = 2279(2) (A)3, Z = 4, Dc= 1.607g/cm3, F(000) = 1128,μ(MoKa) = 1.918 mm-1, the final R = 0.0506 and wR = 0.1382. Each Cu(Ⅱ)ion is coordinated by five oxygen atoms from two benzoic acids, two acetic acids and one methanol molecule in a slightly distorted square pyramidal environment. The title molecules construct a 2-D complex 1 displays strong emissions. IR and TG-DTA studies are also presented.     

Synthesis, Structure and Properties of a Copper Complex Cu2（μ-PhCOO）2（μ-CH3COO）2（CH3OH）2

1 INTRODUCTION Binuclear copper(II) carboxylate complexes have been studied extensively, and most of them are fami- liar binuclear molecule Cu2(RCOO)4L2 with four same bridges[1～5]. However, only a few copper(II) car- boxylate complexes with mixed bridges have been reported, i.e., they have common formulaCu2(R1C- OO)2(R2COO)2L2, such as Cu2(μ- C9H11O4)2(μ-CH3C- OO)2(H2O)2[6],Cu2(μ-PTMMC)2(μ-CH3COO)2(H2O)2[7, 8] and[Cu2(μ-O2CCH3)2(μ-O2CCF3)2(H2O)2]?2CH3CO2H[9…     

Preparation,Characterisation and Properties of Nanocomposites Based on Epoxy Resins – An Overview

An overview about the use of nanoparticles in epoxy resins is given. Deaggregated fumed silica, sol gel materials and other spheroidic nanoparticles improved the abrasion resistance and the mechanical properties of filled epoxides, and several properties can be improved by specific particles. Combustion properties, strength and permeation can be improved by organically modified layered silicates. The proper characterisation of the nanocomposites is still an art. TEM analysis of the cured materials and light scattering with 3D cross-correlation for the liquid samples were sufficient methods for the characterisation of filled epoxides.     

Synthesis and Crystal Structure of a Di-μ_2-phenolic Bridged Binuclear Manganese(Ⅲ) Schiff Base Complex

A new complex [Mn(L)(NCS)]2·0.5CH3CN (H2L = N,N'-bis(chlorosalicylidene)-1,2-diaminoethane) has been synthesized,and its structure (C70H51Cl8Mn4N13O8S4,Mr = 1833.84) was determined by single-crystal X-ray diffraction analysis. The crystal belongs to the monoclinic system,space group C2/c with a = 25.883(2),b = 12.3320(13),c = 13.5951(16) ,β = 112.906(2),V = 3997.2(7) 3,Z = 2,Dc = 1.524 g/cm3,μ(MoKα) = 1.050mm-1,F(000) = 1852,S = 1.098,the final R = 0.0630 and wR = 0.1847 for 2542 reflections with Ⅰ 2σ(Ⅰ). The centrosymmetric title complex contains a dimer in which two distorted octahedral Mn(Ⅲ) centers are bridged equatorially by phenolic oxygen of the Schiff base ligand. The units of the complex are linked via weak C-H···N hydrogen bonds,leading to the formation of 1D chains along the b axis. The weak π-π packing interactions and weak intermolecular C(3)-H(3)···N(3) hydrogen bonds stabilize the crystal structure.     

Addition of HCl to a Cluster-Bound Vinylidene Ligand: Preparation and Structure of Ru5(μ3-SMe)(μ3-CMe)(μ-Cl)(μ-SMe)(μ-PPh2)2(CO)9·PhMe

Addition of aqueous HCl to Ru₅( ₃-C=CH₂)(-SMe)₂(-PPh₂)₂(CO)₁₀ afforded the structurally characterized carbyne complex Ru₅( ₃-SMe)( ₃-CMe)(-Cl)(-SMe)(-PPh₂)₂(CO)₉, formed by addition of H to the vinylidene ligand; a Cl atom bridges an Ru–Ru bond.     

Synthesis and Structure of a New Dinuclear Uranyl Complex

Dinuclear complexes have been widely investigated since 1970s when Robson proposed the conception of dinucleating ligand1,2. These compounds attracted much interests because of their applications as metal-enzemy model in bioinorganic chemistry or promising applications as functional materials. Most of these dinuclear complexes contain d transition metals as central ions. Few dinuclear U complexes have been reported. It is known, in most complexes of axial ion, five donors from ligands shou…     

Preparation and Photocatalytic Characterization of Nanoporous TiO2

Nanoporous TiO2 photocatalysts were prepared by use of controlled drying method with surfactants. The surface area and porous properties are dependent on the chain length of incorporated surfactant cation. The TiO2 materials prepared in the presence of surfactant molecules during the gel formation exhibit much higher photocatalytic activity than that prepared in the absence of surfactants.     

Preparation and Characterisation of Meloxicam Hydroxy Propyl <Emphasis Type="Italic">β</Emphasis>-Cyclodextrin Inclusion Complex

Meloxicam is a non steroidal anti inflammatory drug, used in the treatment of rheumatoid and osteoarthiritis. It is practically insoluble in water and its prolonged use is associated with the incidence of side effects like gastro intestinal perforations, ulcerations and bleeding. Therefore, an attempt has been made to improve the aqueous solubility of the drug by making an inclusion complex using hydroxy propyl β cyclodextrin(HPβ-CD). The complexes were prepared by physical mixture and freeze drying method. The different methods employed for evaluation such as DSC, XRD, SEM and FT-IR studies indicated complete formation of the complex by freeze drying method in a molar ratio of 1:2. The prepared complexes showed improved in-vitro dissolution profile as compared to the pure drug.     

Preparation and reactivity of metal-containing monomers 53. Synthesis and stability of a cluster monomer (μ-H)Os3(μ-OCNMe2)(CO)9PPh2CH2CH=CH2 in solution

The stability of the complex (μ-H)Os₃(μ-OCNMe₂)(CO)₉PPh₂CH₂CH=CH₂ (1), which contains a free unsaturated functional group in the terminal ligand PPh₂CH₂CH=CH₂, with respect to isomerization, chelation of the ligand, and other transformations in solutions was examined. No transformations of complex1 were observed in the course of synthesis from (μ-H)Os₃(μ-OCNMe₂)(CO)₉NMe₃ or upon heating in solution. Complex1 as well as complexes (μ-H)Os₃(μ-OCNMe₂)(CO)₉PHPh₂ and (μ-H)Os₃(μ-OCNMe₂)(CO)₉PPh₃, which were formed as admixtures, were isolated in the solid state and identified by¹H,¹H-{³¹P}, and¹H-{¹H} NMR, IR, and Raman spectroscopy and mass spectrometry. For Part 52, see Ref. 1. Published inIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1455–1460, August, 2000.     

A New Preparation of Mo2(CO)8(μ-PPh2)2 and W2(CO)8(μ-PPh2)2 by a Phosphorus-Carbon Bond Cleavage Reaction. Crystal Structure of a New Polymorph of Mo2(CO)8(μ-PPh2)2

A new synthesis of Mo₂(CO)₈(-PPh₂)₂ and W₂(CO)₈(-PPh₂)₂ by the reaction of molybdenum and tungsten hexacarbonyls with a tetraazamacrocyclic ligand containing —CH₂PPh₂ side chains, comprising cleavage of the phosphorus-methylene bond has been performed. The complexes have been investigated by magnetic and spectroscopic measurements and by single-crystal structure analyses. The structural characterization of a new polymorph of Mo₂(CO)₈(-PPh₂)₂ has been described.     

Synthesis,Characterization and Molecular Structure of a Diiron Complex(μ-SCH_2CH_2CH_2S-μ)Fe_2(CO)_5(Ph_2PCH_3)

The title complex,(μ-pdt)Fe_2(CO)_5(Ph_2PCH_3)(pdt = SCH_2CH_2CH_2S),was obtained by the reaction of the parent complex(μ-pdt)Fe_2(CO)_6 with Ph_2PCH_3 and Me_3NO·2H_2O in good yield(90%). The title complex was characterized by IR,~1H NMR,~(31)P{~1H} NMR and ~(13)C{~1H} NMR spectroscopy as well as by single-crystal X-ray diffraction analysis. The molecular structure shows that the title complex contains a butterfly diiron propanedithiolate cluster with five terminal carbonyls and a monophosphine ligand Ph_2PCH_3. The crystal packing diagram reveals that intermolecular C H···O hydrogen bonds between CH_2 and carbonyls,π-π stacking interactions and van der Waals' interactions stabilize the solid state to form a three-dimensional network.