Preparation, Characterization and Crystal Structure Determination of (C_6H_(14)N)_5(V_5O_(15))

A 1D chain-like organic/inorganic composite material with polyoxovanadates serving as building blocks has been synthesized by the reaction of cyclohexylamine with vana- dium pentoxide, and characterized by IR, UV spectra and TG-DTA technique. The title compound (C30H70N5O15V5, Mr = 995.61) crystallizes in orthorhombic, space group P212121 with a = 6.0093(12), b = 26.780(5), c = 27.979(6) ? V = 4502.6(16) 3, Z = 4, Dc = 1.461 g/cm3, F(000) = 2060, = 1.063 mm-1, R = 0.0651 and wR = 0.1084 for 3426 observed reflections (I > 2(I)). Single-crystal X-ray structural analysis indicates that the title compound consists of five proto- nated cyclohexylamine molecules and a polyoxovanadate anion of V5O155-. In addition, the results of IR spectra and single-crystal X-ray diffraction exhibit that there exists comparatively stronger interaction between the organic groups and polyoxovanadate anion in solid state. Adjacent structure units are bridged through corner-sharing oxygen atoms of VO4 tetrahedra to construct a novel one-dimensional zigzag infinite linear chain arrangement. The curves of TG- DTA elucidate that the process of weight loss of the title compound is divided into two stages, and also reveal that the framework of polyoxovanadate anion decomposes at 473.0 ℃.

Aminolysis of 1-(1-Hydroxybenzotriazolyl)-2,4-dinitrobenzene and 2-(1-Hydroxybenzotriazolyl)-5-nitropyridine

The reaction 1-(1-hydroxybenzotriazolyl)-2,4-dinitrobenzene 1 and 2-(1-hydroxybenzotriazolyl)-5-nitro-pyridine 2 with amines undergoes amination followed by elimination of the 1-hydroxyl benzotriazolyl anion. The kinetic data for the reaction of 1 and 2 with Mo, CHA and An in MeOH and AN proceeded by uncatalysed mechanism in which the rate limiting step is the leaving group departure, whereas the reaction with Mo in toluene proceeded by uncatalysed mechanism in which the formation of the zwitterionic intermediate is the rate determining step. While the reactions of 1 with CHA and An and the reaction of 2 with CHA in toluene proceeded by SB mechanism in which the rate determining step is the proton transfer process. The reactions of 1 and 2 with Mo in the three solvents and with CHA and An in MeOH and AN is greatly depended on the stability of the zwitterionic intermediate. The effect of ring activation is due to the ground state stabilization and the more efficient delocalization of the negative charge with a nitro group than with a ring-nitrogen in the transition state. The low activation enthalpies ΔH# and the highly negative activation entropies ΔS# are due to the intramolecular hydrogen bonding with the ammonio hydrogen present in the transition state.

A general synthesis of transition metal oxides with assistance of organic amines and their electrocatalytic properties

Several transition metal oxides,including α-Fe2O3,Fe3O4,Co3O4,NiO,CuO and ZnO,were synthesized via an easily controlled hydrothermal method at assistance of organic amine(cyclohexylamine or triethylamine).The synthesized samples were identified and characterized by X-ray diffraction(XRD),Transmission Electron Microscopy(TEM),High-resolution Electron Microscopy(HR-TEM),Field Emission Scanning Electron Microscopy(FE-SEM),N2 adsorption/desorption measurement.The resultant metal oxides displayed various morphologies in shape.The as-prepared samples were used as electrocatalysts(CuO was excluded) modified on a glassy carbon electrode for p-nitrophenol reduction in a basic solution.Fe3O4 and Co3O4 samples showed higher catalytic activities.