A new Co(II) complex with N,O-donor Schiff base: Synthesis, structure and characterization

A new Co(II) complex with tridentate Schiff base ligand with a N,N,O donor set has been synthesized and characterized by single X-ray technique and spectroscopic techniques. The thermochemical properties have been studied. X-ray structure analysis of the title compound Co(II)L₂ [HL = 2-methyl-6-(2′-hydroxybenzylideneamino) pyridine] shows that the polyhedron around Co(II) is a distorted tetrahedron, and the self-assembly via intermolecular π-π interactions leads to a three-dimensional network. Crystal data for the title complex C₂₆H₂₂CoN₄O₂: Monoclinic, space group Ia, a = 11.741(7) Å, b = 8.149(5) Å, c = 22.764(16) Å, β = 98.530(12)°, V = 2154(2) ų, Z = 4.     

三元配合物钯（Ⅱ）-2,2''-联吡啶-L-天冬氨酸与DNA作用研究

The ternary complex Pd(Ⅱ)-2,2‘-bipyridine-L-asparagic acid was synthesized and characterized by elemental analysis, IR-spectra and molar conductance. The formula of the complex is Pd(bipy)(L-asp). The interaction of the complex with DNA has been studied by UV-spectra, fluorescence spectra, CD-spectra and gel electrophoresis. The results showed that the interaction of the complex with DNA performed mainly in intercalative mode and the extent of interaction was dependent on the concentration of the complex.     

Synthesis and Characterization of Novel Organosoluble Methyl Substituted Poly(aryl Ether Ketone)s Containing Sulfone Linkage

Several new methyl substituted poly(aryl ether ketone)s containing sulfone linkage with inherent viscosities of 0.62–0.84 dL/g have been prepared from 4,4′‐bis(2‐methylphenoxy)diphenylsulfone and 4,4′‐bis(3‐methylphenoxy)diphenylsulfone with terephthaloyl chloride and isophthaloyl chloride by electrophilic Friedel‐Crafts acylation in the presence of DMF with anhydrous AlCl₃ as a catalyst in 1,2‐dichloroethane, respectively. These polymers having weight‐average molecular weight in the range of 71,000–49,000 are all amorphous and show high glass transition temperatures ranging from 167 °C to 191 °C, excellent thermal stability at temperatures over 400 °C in air or nitrogen, high char yields of 51–58% in nitrogen and good solubility in CHCl₃ and polar solvents such as DMF, DMSO and NMP at room temperature.     

Polymer bound glutamic acid salicylaldehyde Schiff‐base complex ­catalyst for oxidation of olefins with ­dioxygen

The polymer bound Schiff‐base ligand (PS‐SalGlu) has been prepared from polystyrene bound salicylaldehyde and glutamic acid, and its complex (PS‐SalGlu‐Co) has also been synthesized. The polymer ligand and its complex were characterized by infrared spectroscopy, small area X‐ray photoelectron spectroscopy, and inductively coupled plasma‐atomic emission spectro (ICP‐AFS). In the presence of the complex, cyclohexene can be effectively oxidized by molecular oxygen without reductant. The long‐chain linear aliphatic olefins, such as 1‐octene, 1‐decene, 1‐dodecene and 1‐tetradecene, can be directly oxidized by molecular oxygen catalyzed by PS‐SalGlu‐Co, which affords the 1,2‐epoxy alkane. Copyright © 2001 John Wiley & Sons, Ltd.     

Cooperative C-F...Si interaction in optically active helical polysilanes

Cooperative amplification of the C-F...Si weak interaction between side chains and the main chain was found to afford rigid rodlike helical polysilanes with a preferential screw sense.     

Site-directed exchange studies with combinatorial libraries of nanostructures

We describe a new combinatorial method for studying the exchange between solution adsorbates and nanoscale features within libraries generated via dip-pen nanolithography. Four different compounds, 1-octadecanethiol, 16-mercaptohexadecanoic acid, ferrocene (11-mercaptoundecyl), and ferrocene (11-mercapto-1-oxoundecyl), are studied on amorphous and single-crystal gold substrates. This series of adsorbates allows us to compare the exchange properties of patterns of nanoscale features as a function of composition, feature size, and type of underlying substrate. Moreover, these properties can be compared and contrasted with bulk SAM properties. The novel strategy provides not only a method for initiating site-specific exchange processes but also a way of extracting kinetic information about the rate of such processes in situ.     

Ammonia removal of activated carbon fibers produced by oxyfluorination

In this study, activated carbon fibers (ACFs) were produced by an oxyfluorination treatment to enhance the capacity of ammonia gas removal. The introduction of polar groups, such as CF, CO, and COOH, on the ACFs was confirmed by a XPS analysis, and N2/77 K adsorption isotherm characteristics including specific surface area and total and micropore volumes were studied by the BET and t-plot methods. The ammonia-removal efficiency was confirmed by a gas-detecting tube technique. As a result, the specific surface area and micropore volume of ACFs were slightly destroyed as the surface treatment time was increased. However, the oxyfluorinated ACFs led to an increase of fluorine and oxygen-containing polar functional groups in ACF surfaces, resulting in an increase in the ammonia-removal efficiency of the ACFs produced.     

The adsorption of triethylenediamine on Al(2)O(3)-I: a vibrational spectroscopic and desorption kinetic study of surface bonding

The adsorption of triethylenediamine (TEDA) at 300 K is observed to occur via hydrogen bonding to isolated Al-OH groups on the surface of partially dehydroxylated high area gamma-Al(2)O(3) powder. This form of bonding results in +0.3 to +0.4% blue shifts in the CH(2) scissor modes at 1455 cm(-1) and a -0.4% red shift in the CN skeletal mode at 1060 cm(-1), compared to the gas-phase frequencies. Other modes are red shifted less than 0.1%. The isolated OH modes are red shifted by -200 to -1000 cm(-1) due to the strong hydrogen bonding association of Al-OH groups with an N atom in TEDA. Thermal desorption of adsorbed TEDA from the surface occurs in the range 300-700 K. Mass spectral and infrared studies indicate that the decomposition of TEDA occurs on Al(2)O(3) above 725 K, and that C-H bonds are broken, forming adsorbed species with N-H bonds which are stable to 1000 K or above. In contrast to adsorption at 300 K, adsorption of TEDA at 85 K results in the formation of a condensed ice of TEDA, which covers the outer surface of the porous Al(2)O(3) and which does not interact with Al-OH groups inside the porous powder due to immobility.