Synthesis of α,ω‐Bis(oxazolidinone)polyoxyethylene via a Lithium Bromide–Catalyzed Reaction of Oligoethylene Glycol Diglycidyl Ethers with Isocyanates

The synthesis of bis(oxazolidinone)polyoxyethylene derivatives 2a–h from oligoethylene glycols diglycidyl ethers 1a–e and isocyanates is reported. The reaction was achieved by lithium bromide and tributylphosphine oxide. These bis‐oxazolidinones may have important antibacterial activity.     

Synthesis of Quinoxalinophenazine Derivatives and Reaction of 3,12-Dimethylbenzo[a]quinoxalino-[2,3-c]phenazine with Mercury(Ⅱ) Bromide: Spectral and Structural Characterization

A new series of quinoxalinophenazine derivatives were synthesized in good yields by the reaction of 2,3-dibromonaphthalene-1,4-dione with different aryl-1,2-diamines in DMF as solvent at 120~130℃ or under reflux conditions. 3,12-dimethylbenzo[a]quinoxalino[2,3-c] phenazine with bidentate character reacts with mercury(II) bromide to give suitable crystals. All products were confirmed by IR, 1H and 13 C NMR, and the metal complex by single-crystal X-ray method. The crystal(C24H16Br2HgN4, Mr = 720.82) belongs to the triclinic system, space group P1 with a = 10.186(6), b = 10.421(6), c = 11.470(7) , α = 98.670(7), β = 95.069(7), γ = 109.831(7)o, V = 1119.4(12) 3, Z = 2, Dc = 2.139 Mg/m3, μ = 10.46 mm-1, F(000) = 676, R = 0.043 and wR = 0.115 for 3982 observed reflections with I 2σ(I).     

The Reaction of 2,5-Bis(Dimethyfurfuryl)Furan Dialdehyde with Primary α,ω-Diamines

Abstract

The influence of the H-bond acceptors strength of het-eroatoms present in α,ω-diamines on the reaction course leading to the formation of macrocyclic Schiff bases was studied. For strong acceptors like oxygen and nitrogen atoms the highest yield was obtained. Similar effect was observed for diamines possessing two oxygen atoms, while the presence of three oxygen resulted only in polymerisation reactions.     

The Reaction of Alkenes with Triangulo-Clusters [Pt3(μ-CO)3(PR3)3]

The reactions of the cluster complexes [Pt₃(-CO)₃L₃], where L=PPh₃ 1a, PPh₂Bz 1b and PCy₃ 1c, with activated mono-olefins have been studied under preparative and equilibrium conditions. At low temperature the olefins react quantitatively giving the adducts [Pt₃(-CO)₃L₃(olefin)] (olefin=trans-dicyanoethene, DCE 2a–2c, maleic anhydride, MA 3a–3c). The stereo-chemistry of these unstable clusters has been deduced from low temperature ³¹P, ¹³C, ¹⁹⁵Pt-NMR and I.R. spectra. At higher temperature these adducts in presence of excess of olefin convert quantitatively to stable mononuclear Pt(0) complexes [Pt(CO)L(olefin)] (olefin=DCE 4a–4c, MA 5a–5c, maleimide, MI 6a–6c and 1–4-naphthoquinone, NQ 7a, 7c).     

New Subsidiary Interaction Mode of Counteranions with the Periphery Cavity of Calix[4]pyrroles Binding with the Anion Subunits

Calixpyrroles, an easy-to-make class of neutral macrocycles, are effective and selective receptors for anions in the solution and in the solid state1,2. Their anion recognition characteristics have attracted extensive interest. Various functionalized cali…     

Cleavage of B−C bonds and Anion [PhBH3]− Formation in the Reaction of the Yb(II) Hydride Complex with BPh3

Russian Journal of Coordination Chemistry - The reaction of the amidinatehydride complex of divalent ytterbium [(Amd)YbII(μ2-H)]2 (Amd is {tert-BuC(NC6H3-iso-Pr2-2,6)2}) with BPh3 proceeds...     

Synthesis and Characterization of 2-Mercapto-1-cyclohexylimidazole–Based Zinc(II) and Cadmium(II) Bromide Complexes: The Crystal Structure of [Zn(Hmim chexyl )2(Br)2] with N–H…Br Intermolecular Hydrogen Bonding Interactions

Reactions of the ligand 2-mercapto-1-cyclohexylimidazole (Hmim^chexyl) with both zinc(II) and cadmium(II) bromides in ethanol solutions afforded 2:1 complexes of the type [M(Hmim^chexyl)₂(Br)₂] (M = Zn 1, and Cd 2) with an MBr₂S₂ configurations. Spectroscopic evidence (FT-IR and ¹H-¹³C NMR) confirms that the exocyclic thione sulfur atoms are the donors in both complexes. Complex 1 crystallizes in a monoclinic system, space group C2/c, a = 16.180(3), b = 10.817(5), c = 13.602(3); α = 90, β = 106.754(17), γ = 90; Z = 4; R1 = 0.0229, wR2 = 0.0554. The coordination geometry about the zinc(II) atom is distorted tetrahedral with average Zn-S and Zn-Br bond lengths of 3.3418(8) and 2.4017(6) Å, respectively. The bromide ions form intermolecular N–H…Br hydrogen bonding with the thione NH groups of the ligand molecule.     

Reaction of [VO(OPr)3] with hexamethyldisylthiane in the presence of β-diketones

The reaction of [VO(OPr)₃] (Pr is n-propyl) with hexamethyldisylthiane Me₃SiSSiMe₃ in the presence of β-diketones (acetylacetone (HAcac), hexafluoroacetylacetone (Hfac), and dipivaloylmethane (Dpm)), is studied. In all cases, vanadium(IV) and vanadium(III) β-diketonate complexes of different types are formed. New crystalline modification [V(Acac)₃] is obtained in the reaction with HAcac. The mixedligand vanadium(III) complex of the composition [V₂(Hfac)₂(μ-OPr)]₂ is formed with Hfac. In the presence of Dpm, the known vanadium(IV) complex [V₂O₂(Dpm)₂(μ-OPr)₂] is obtained in which two vanadyl groups VO²⁺ are linked by two bridging propoxy groups. The structures of all products are determined by X-ray diffraction analysis.     

Synthesis and structure of bismuth complexes [Ph3MeP] 2 + [BiI3.5Br1.5(C5H5N)]2− · C5H5N, [Ph4Bi] 4 + [Bi4I16]4− · 2Me2C=O, and [Ph3(iso-Am)P] 4 + [Bi8I28]4− · 2Me2C=O

Complexes [Ph₃MeP] ₂ ⁺ [BiI_3.5Br_1.5(C₅H₅N)]^2? · C₅H₅N(I), [Ph₄Bi] ₄ ⁺ [Bi₄I₁₆]^4? · 2Me₂C=O (II), and [Ph₃(iso-Am)P] ₄ ⁺ [Bi₈I₂₈]^4? · 2Me₂C=O (III) were synthesized by reactions of bismuth iodide with triphenylmethylphosphonium bromide, triphenylbismuthonium sulfosalicylate, and triphenylisoamylphosphonium iodide, respectively. The crystal structures of complexes I–III were determined by X-ray crystallography. The complexes contain, in addition to cations and solvent molecules, mono-, tetra-, and octanuclear anions, in which bismuth atoms are in octahedral coordination.     

The electrode modified with Langmuir–Blodgett film of p-tert-butylcalix[4]arene derivatives with sulfur-containing functionalities for the determination of silver

A new voltammetric sensor, based on a new p-tert-butylcalix[4]arene derivative (TCAD) modified glassy carbon electrode (GCE) using Langmuir–Blodgett (LB) technique, was designed successfully and used for recognition and determination of Ag⁺. The π?-?A isotherms suggested that the monolayer of TCAD can coordinate with Ag⁺ at the air–water surface. Under the optimum experimental conditions, this voltammetric sensor shows a linear voltammetric response for Ag⁺ in the range of 1.0?×?10^?8?～?6.0?×?10^?6?mol?L^?1 with detection limit 5.0?×?10^?9?mol?L^?1. The high sensitivity, selectivity, and stability of this LB film modified electrode also demonstrate its practical application for a simple, rapid and economical determination of Ag⁺ in water sample.     

Vibrational spectra of tropylium tetrahaloborates [C7H7] [BX4] (X  Br or I)

Raman and i.r. studies of the title compounds, which are salts of the planar D_7h tropylium cation, provide complete sets of vibrational frequencies for the tetrahaloborate anions, including Raman data for [BI₄]⁻ for which ν₁(a₁) = 169, ν₂(e) = 83, ν₃(t₂) = 515 (¹¹B), 543 (¹⁰B) and ν₄(t₂) = 117 cm⁻¹.     

Reaction of [Ru(CO)H(NCMe)2(PPh3)2]ClO4 with 1-hydroxymethyl-3,5-dimethylpyrazole. Formation of an amidine complex. The crystal structure of [Ru(CO)H{NHCMe(Me2pz)}(PPh3)2]ClO4

The reaction between [Ru(CO)H(NCMe)₂(PPh₃)₂]ClO₄ and 1-hydroxymethyl-3,5-dimethylpyrazole has been shown by spectroscopic and X-ray crystallographic methods to give the amidine complex [Ru(CO)H{NHCMe(Me₂pz)}(PPh₃)₂]ClO₄.     

Coupling Reaction of 4-Chloro-7-H-Pyrrolo[2,3-d]Pyrimidine with 2,3,5-Tri-O-Acetyl-β-D-Ribofuranosyl Chloride

Tubercidin (4-amino-7--D-riobofuranosyl-7-H-pyrrolo[2,3-d]pyrimidine) 1, an antibio-tic substance produced in the culture broth of Streptomyces tubericidus1, is an adenosine analog in which N-7 is replaced by a carbon atom. It has attracted much attention due to the biological activities for the growth inhibition of certain tumors, and many derivatives of tubercidin have been synthesized2-5.For the synthesis of tubercidin analogs, 4-chloro-7-H-pyrrolo[2,3-d]pyrimidine-2,3,5-tri-O-acetyl--D-r…     

Synthesis and structure of bismuth-containing complexes [(Ph4BiO)2{2,5-(CH3)2C6H3S(O)}] 2 + [Ph2Bi2I6]2−,[(Ph4Bi]+[PhBi(C5H5N)I3]−, [Ph4Sb] 4 + [Bi4I16]4−⋅2(CH3)2 C=O, and [Ph4Sb] 3 + [Bi5I18]3−

The reactions of tetraphenylbismuthonium and -stibonium salts Ph₄EX (E = Bi, Sb; X = I, OSO₂ (C₆H₃(CH₃)₂-2,5), OSO₂C₆H₃(OH-4)(COOH-3)) with bismuth triiodide in acetone afford complexes [Ph₄Bi]⁺[PhBi(C₅H₅N)I₃]^-, [(Ph₄BiO)₂S(O){2,5-(CH₃)₂C₆H₃S(O)} [Ph₂Bi₂I₆]^2–, [Ph₄Sb [Bi₄I₁₆]^4-·2(CH₃)²C=O, and [Ph₄Sb] ₃₊ ⁺ [Bi₅I₁₈]^3-, whose structural units, according to the X-ray diffraction data, are tetraphenylbismuthonium (-stibonium) cations and mono-, di-, tetra-, and pentanuclear anions, respectively.     

Synthesis and Crystal Structure of Bis[2-[2-(diethylamino)ethyliminomethyl]-4-nitrophenolato]dimethanolcobalt(II) Dinitrate

1 INTRODUCTION The significance of cobalt coordination com- pounds in biological systems is recognized[1～3]. In many instances the cobalt coordination compounds of Schiff bases have been suggested as models to describe energy transfer in naturally occurring systems. In such cases the coordination sphere about the metal ion is believed to play an important role in determining the nature of the model system[4, 5]. In order to investigate the structures of such complexes, we report herein t…     

Dimer of Bis[trans-5-methyl-2-[2-(4-methoxylphenyl) ethenyl]-benzoxazole]di-μ-nitratosilver(I)

The title complex [AgNO3(C17H15NO2)2]2 was synthesized and characterized by X-ray diffraction analysis. The compound crystallizes in triclinic, space group Pī with a = 11.226(7), b = 11.906(7), c = 12.144(7) (A。), α = 99.796(10), β = 91.631(10), γ = 101.225(10)°, V = 1565.6(16)(A。)3, Z = 1, Mr = 1400.96, Dc = 1.486 g/cm3, F(000) = 716 and μ(Mo-Kα) = 0.697 mm-1. The final R and wR are 0.0401 and 0.0995, respectively for 5492 independent observable reflections with I > 2σ(I). The results show that the central Ag atom is four-coordinated with two O atoms from two distinct NO3- anions and two N atoms from two trans-5-methyl-2-[2-(4-methoxylphenyl)ethenyl]- benzoxazole ligands, and the two Ag atoms bridged with two O atoms give an interesting Ag-O-Ag-O parallelogram structure. The coordination sphere of Ag atom exhibits a heavily distorted tetrahedral geometry and the coordination angles lie in the range of 66.73(12)～129.59(10)°. The intra- molecular dihedral angles between the benzoxazolyl and phenyl planes are 4.1(3) and 2.9(3)°, respectively.     

Synthesis and Antioxidant Properties of Bis[ω-(3,5-dialkyl-4-hydroxyphenyl)alkyl] Sulfides

The reaction of -(3,5-dialkyl-4-hydroxyphenyl)-1-chloroalkanes with sodium sulfide yielded the corresponding sulfides, which were tested as antioxidants in two model reactions: oxidation of lard and Vaseline oil.