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31.
1-Bromo-1-fluoro-[1a,2,7,7a]-tetrahydro-1H-cyclopropa[b]naphthalene (19) has been prepared by the addition of bromofluorocarbene to 1,4-dihydronaphthalene (18). Treatment of a solution of 19 in dry ether with MeLi afforded the tricyclic hydrocarbon 17, resulting from the intramolecular C-H insertion of carbene 16, and two dimerization products, the head-to-head 20 and head-to-tail 21 allene dimers, confirming the formation of title cycloallene 15 as a reactive intermediate. B3LYP/6-31G(d) calculation predicts the activation barriers for insertion product 17 and allene product 15 as 3.70 and 9.52 kcal/mol, respectively. This prediction was in good agreement with our experimental results. 相似文献
32.
T. Ceyhan A. Altındal A.R. Özkaya Ö. Çelikbıçak B. Salih M. Kemal Erbil Ö. Bekaroğlu 《Polyhedron》2007
The phthalodinitrile derivative 1 was prepared by the reaction of 4-nitrophthalonitrile and 1,3-dimethoxy-4-tert-butylcalix[4]arene in dry dimethylsulfoxide as the solvent, in the presence of the base K2CO3, by nucleophilic substitution of an activated nitro group in an aromatic ring. The tetramerization of compound 1 gave a binuclear zinc(II) phthalocyanine and a metal-free phthalocyanine of the ball type, 2 and 3, respectively. Its condensation with 4,5-bis(hexylthio)phthalonitrile results in a binuclear phthalocyanine of the clamshell type, 4. The newly synthesized compounds were characterized by elemental analysis, UV–Vis, IR, MS and 1H NMR spectra. The electronic spectra exhibit an intense π → π∗ transition with characteristic Q and B bands of the phthalocyanine core. The electrochemical properties of 2–4 were examined by cyclic voltammetry in non-aqueous media. The voltammetric results showed that while there is no considerable interaction between the two phthalocyanine rings in 4, the splitting of a molecular orbital occurs as a result of the strong interaction between the phthalocyanine rings in 2 and 3. 相似文献
33.
ÜMIT ÇAKIR Y. Kemal Yildiz Mahir Alkan 《Journal of inclusion phenomena and macrocyclic chemistry》1999,34(2):155-167
Liquid-liquid extractive-spectrophotometric studies of sodium ion complexes of 18-crown-6(18C6), dibenzo-18-crown-6(DB18C6), 15-crown-5(15C5), and 12-crown-4(12C4) and anionic dyes [4-(2-pyridylazo)-resorcinol monosodium salt monohydrate (PAR), Eriochrom Black T (EBT), and methyl orange (MOR)] and sodium picrate (PICRAT) as the counter ion are described. The overall extraction equilibrium constants for the 1 : 1 complexes of the above crown ethers with sodium dyes between different organic solvents and water have been determined at 25deg;C. They were conducted in various solvent-water systems maintaining an identical initial cation concentration in water, [M0+]w, and macrocyclic ligand concentration in the organic phase, [L0]org}, so that in all extractions [M0+]w : [L0]org ratios were 1 : 1, 1 : 10, 1 : 20, 1 : 50, and 1 : 62.5. An ion association complex formed between the sodium-crown ether complex ion and a dye anion was extracted into the organic solvent, and then the dye concentration of the separated aqueous phase was measured with an ultraviolet-visible spectrophotometer. PAR was the best associated dye with all crown ethers sodium-dyes and the extracted dye occurs as the ion-pair complex. Methylene chloride was found to be better than other extractive solvents used in this study. 相似文献
34.
The most sensitive atomic spectrometric technique has been ETA-AAS for many years. Recently, ICP-MS has emerged as an approach which provides even lower detection limits, but at considerably higher instrument and running costs. Flame AAS, on the other hand, is still being used widely in many laboratories in world. Therefore, alternative approaches for better sensitivity using flame AAS should be relevant and important. 相似文献
35.
Nazan Ocak Ískeleli amil Ik Kemal Sancak Selami amaz Yasemin Ünver Mustafa Er 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(6):o363-o365
The title compounds, C12H20N6O2, (I), and C5H9N3O2, (II), display the characteristic features of 1,2,4‐triazole derivatives. Compound (I) lies about an inversion centre which is at the mid‐point of the central C—C bond. Compound (II) also contains a planar 1,2,4‐triazole ring but differs from (I) in that it has a hydroxy group attached to the ring. Molecules of (I) are held together in the crystal structure by intermolecular N—H⋯O contacts and by weak π–π stacking interactions between the 1,2,4‐triazole moieties. Compound (II) contains intermolecular O—H⋯O and N—H⋯O hydrogen bonds. 相似文献
36.
Single and dual substituent correlation analysis were applied to study transmission of substituent effects on IR carbonyl and thiocarbonyl stretching frequencies of 4-substituted phenyl-4,5-dihydrobenzo [f] [1,4] oxazepin-3 (2H)-ones (5a–n) and -thiones (6a–n). The substituent effects were estimated on the basis of results of the statistical analysis. The differences among the regression coefficients were discussed in terms of the relative importance of the substituent field and resonance effects. For a better understanding of the results, density functional theory (DFT) calculations were performed to determine the preferred geometry and to calculate the theoretical carbonyl and thiocarbonyl stretching frequencies. 相似文献
37.
In this study, Tungsten Oxide (WO3) thin films were prepared by Chemical Spray Pyrolysis (CSP) and Spin Coating (SC) techniques and it was investigated effects of technique and parameter on the films. WO3 thin films were deposited on ITO (Indium Tin Oxide) coated glasses. The structural, optical and electrochromic properties of the WO3 thin films were characterized by XRD, SEM, UV, and CV measurements. The sharpest (200) peak was observed in the XRD spectra and optical band gaps were calculated around 2.6~3.1 eV via UV-Vis spectra for all of the samples. Micro fibrous reticulated surface (filamentous like) morphology for the films deposited by CSP technique and smooth surface morphology with high optical transmittance for the film deposited by SC Technique were obtained from SEM images. In addition to these results, it was revealed that all the samples exhibit good electrochromic performance. 相似文献
38.
Rasim Dermez S. Abdel Khalek Kemal Kara Bekir Deveci G. N. Günayd?n 《Journal of Russian Laser Research》2012,33(1):42-51
Our aim is to investigate the entanglement dynamics and quantum correlations of a full-trapped ion interacting with two time-independent
laser beams in view of the Lamb–Dicke parameter. For this purpose, the three probability amplitudes in the trapped ion is
taken as ?{1