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Three novel vic-dioxime ligands containing the 1,8-diamino-3,6-dioxaoctane group, N,N′-(1,8-diamino-3,6-dioxaoctane)-p-tolylglyoxime (L1SL1H4), N,N′-(1,8-diamino-3,6-dioxaoctane)-phenylglyoxime (L2SL2H4), and N,N′-(1,8-diamino-3,6-dioxaoctane)-glyoxime (L3SL3H4) have been prepared from 1,8-diamino-3,6-dioxaoctane with anti-p-tolylchloroglyoxime, anti-phenylchloroglyoxime or anti-monochloroglyoxime. Polynuclear complexes [M(L
x
SL
x
)]
n
or [M(L
x
SL
x
)(H2O)]
n
(x = 1, 2 and 3), where M = CuII, CoII, and NiII, have been obtained with 1:1 metal/ligand ratio. The CuII and NiII poly-metal complexes of these ligands are proposed to be square planar, while also the prepared CoII complexes are proposed to be octahedral with two water molecules as axial ligands. The detection of H-bonding in the [Ni(L1SL1)]
n
, [Ni(L2SL2)]
n
and [M(L3SL3)(H2O)]
n
metal complexes by FT i.r. spectra revealed the square planar or octahedral [MN4·H2O)]
n
coordination of poly-nuclear metal complexes. [MN4]
n
coordination of the [Ni(L1SL1)]
n
and [Ni(L2SL2)]
n
complexes were also determined by 1H-n.m.r. spectroscopy. The ligands and poly-metal complexes were characterized by elemental analyses, FT-i.r., u.v.-vis.,
1H and 13C-n.m.r. spectra, magnetic susceptibility measurements, molar conductivity, cyclic voltammetry, and differential pulse voltammetric
(DPV) techniques. 相似文献
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J. Huub Adriaanse Sven H.C. Askes Yorrick van Bree Stefan van Oudheusden Eelke D. van den Bos Esref Günay Ilpo Mutikainen Urho Turpeinen Gerard A. van Albada Jaap G. Haasnoot Jan Reedijk 《Polyhedron》2009,28(14):3143-3149
A variety of new coordination compounds with transition-metal salts and the ligand trimethyl[1,2,4]triazolo[1,5-a]pyrimidine (abbreviated as tmtp) is described, together with several of their 3D crystal structures and spectroscopic and magnetic properties. The compounds were selected based on the coordination ability of the counterion, halide, nitrate, sulfate, thiocyanate and perchlorate. The formed coordination compounds and their coordination numbers were found to be strongly dependent on both the cation and the used counter-anion. The several compounds studied have the following structural formulae: [CuCl2(tmtp)2], [CuBr2(tmtp)2], [ZnBr2(tmtp)2], [Cu(NO3)2(tmtp)2], [CuSO4(tmtp)2]2(H2O)(MeOH), [Cu(H2O)(NCS)2(tmtp)2], [Zn(NCS)2(tmtp)2], [Cd(NCS)2(tmtp)2] and [M(H2O)2(tmtp)4](BF4)2, in which M = Co, Ni, Zn.The new coordination compounds have been further characterized by NMR, (far-)IR and LF spectra, as well as by C, H, N element analyses, and EPR spectra for the Cu(II) compounds. The coordination around the metal varies from 4 (Zn, Cu), via 5 (Cu) to 6 (for Co, Cu and Cd). The anions usually complete the coordination sphere; only the Co and Zn compounds with the tetrafluoridoborate anions have no coordinated anions, but water ligands complete the octahedral coordination sphere. In the 5-coordinated [Cu(H2O)(NCS)2(tmtp)2] water completes the square pyramid geometry. 相似文献
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In this study, the synthesis, spectroscopic, catalytic, and electrochemical properties of salicylaldimine Schiff-base ligands (Ln) and their dinuclear Pd(II) complexes for L1 and L2 ligands with mononuclear Pd(II) complexes for L3 and L4 ligands were investigated. The ligands and their mono- or dinuclear Pd(II) complexes were characterized by FT-IR, UV-Vis, 1H NMR and elemental analysis, as well as through magnetic susceptibility and spectroelectrochemical techniques. The catalytic studies showed that the introduction of tert butyl groups on the salicyl ring of the molecules increased the catalytic activity towards hydrogenation of nitrobenzene and cyclohexene in DMF at 25 and 45 °C. It was also observed that the steric hindered mono- and dinuclear Pd(II) complexes were thermally stable complexes and were not sensitive to air or the moisture. The complexes were easily prepared from cheap materials that could be used as versatile and efficient catalysts for different C-C coupling reactions (Suzuki-Miyaura reactions). 相似文献
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Hoang HT Tong HD Segers-Nolten IM Tas NR Subramaniam V Elwenspoek MC 《Journal of colloid and interface science》2012,367(1):455-459
We present a new and simple approach to fabricate wafer-scale, thin encapsulated, two-dimensional nanochannels by using conventional surface-micromachining technology and thin-film evaporation. The key steps to the realization of two-dimensional nanochannels are a fine etching of a sacrificial layer to create underetching spaces at the nanometer regime, and an accurate thin-film evaporation for encapsulation. Well-defined cross-sectional, encapsulated nanochannel arrays with dimensions as small as 20 nm in both width and height have been realized at the wafer-scale. The fabricated nanochannels with a channel length of 10mm have been used as a suitable fluidic platform for confining a solution containing nanomolar concentrations of Alexa fluorescent molecules. Initial results toward visualization of single Alexa molecules in the confined solution are reported. 相似文献
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The thermal decomposition of three new reagent cyclohexylamine-p-tolylglyoxime (L1H2), tertiarybutyl amine-p-tolylglyoxime (L2H2) and secondary butylamine-p-tolylglyoxime (L3H2 and their Co-complexes were studied by both isothermal and nonisothermal methods. As expected, the complex structure of Co-complexes,
different steps with different activation energies were realized in decomposition process. Model-fitting and model-free kinetic
approaches were applied to nonisothermal and isothermal data. The kinetic triplet (f(α), A and E) related to nonisothermal model-fitting method can not be meaningfully compared with values obtained from isothermal method.
The complex nature of the multi-step process of the studied compounds was more easily revealed using a wider temperature range
in nonisothermal isoconversional method. 相似文献
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A simple method using spin-deposition and sacrificial layer etching is used to fabricate all-polyimide nanochannels (100 and 500 nm channel height). Channels are characterized using spontaneous capillary filling with water, ethanol and isopropanol, and with electroosmotic flow. The channels can be produced with simple cleanroom equipment, namely spinning and metal deposition facilities. Polyimide is an excellent material for micro- and nanofluidic channels due to its favourable electrical and mechanical properties and its biocompatibility. 相似文献