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991.
《中国化学会会志》2017,64(11):1340-1346
In this investigation, we describe substituent effect on the dipole moment, ionization potential, electron affinity, structure, frontier orbitals energy, in the trans‐Cl(OC)(H3P)3W(≡C‐para‐C6H4X) (X = H, F, SiH3, CN, NO2, SiMe3, CMe3, NH2, NMe2) complexes using MPW1PW91 quantum chemical calculations. The nature of chemical bond between the [Cl(OC)(H3P)3W]− and [C‐para‐C6H4X]+ fragments was illustrated with energy decomposition analysis (EDA). Percentage composition in terms of the defined groups of frontier orbitals for these complexes was inspected to investigate the character in metal–ligand bonds. Quantum theory of atoms in molecules (QTAIM) was used for illustration of metal–ligand bonds in these complexes. 相似文献
992.
《中国化学会会志》2017,64(7):727-731
Mn‐[4‐chlorophenyl‐salicylaldimine‐methylpyranopyrazole]Cl2 ([Mn‐4CSMP ]Cl2) as nano‐Schiff base complex was prepared and fully characterized by Fourier transform infrared spectroscopy, X‐ray diffraction, thermal gravimetric analysis, derivative thermogravimetry, scanning electron microscopy, energy‐dispersive X‐ray analysis, and UV–vis spectroscopy. The reactivity of nano‐[Mn‐4CSMP ]Cl2 as a catalyst was tested on the tandem cyclocondensation–Knoevenagel condensation–Michael reaction between phenylhydrazine and ethyl acetoacetate with various aromatic aldehydes to give 4,4′‐(arylmethylene)‐bis‐(3‐methyl‐1‐phenyl‐1H ‐pyrazol‐5‐ol)s derivatives. 相似文献
993.
《Chemie in Unserer Zeit》2017,51(2):86-95
The platinum complex cisplatin is in worldwide use since 1978 as anticancer agent. Disadvantages of the cisplatin therapy are both drug resistance and severe side effects. To avoid these drawbacks several strategies have been developed in tumor research. Patients treated with second‐generation platinum complexes experience already less severe side effects. Organometallic and coordination complexes with different metals can be used to target DNA as well as overexpressed proteins and enzymes in cancer cells. In contrast, delivery systems for anticancer drugs target cancer cells, while being selectively accumulated in tumor tissue. 相似文献
994.
《中国化学会会志》2017,64(6):612-617
We report a new, unique process for the design of poly(2‐hydroxyethyl methacrylate) (PHEMA )‐based hybrid materials, which involves the coating of PHEMA on TiO2 and TiO2 /Ag nanoparticle surface under visible light. New hybrid materials initiated under different conditions were prepared under visible light, which could be used for the theoretical design of nanohybrid materials. The hybrid materials thus prepared were characterized by Fourier transform infrared spectroscopy (FTIR ), transmission electron microscopy (TEM ), and thermogravimetric analysis (TGA ). The experimental results confirmed the successful synthesis of TiO2–PHEMA hybrid materials. Compared to other methods, the method reported here involving the direct combination of PHEMA on the TiO2 surface was simply catalyzed by visible light without the addition of initiators. 相似文献
995.
《中国化学会会志》2017,64(7):833-842
In the present work, the cobalt(II ) synergist complex with isobutyric acid (HLI ) and 5‐hydroxy‐4‐octanone oxime (HBI ), which were the corresponding short‐chain analogs of active synergistic mixture of Versatic10 (HL ) and Lix63 (5,8‐diethyl‐7‐hydroxy‐6‐dodecanoneoxime, HB ), was prepared and studied by X‐ray single‐crystal diffraction. The crystal structure of the cobalt(II ) synergistic complex showed that the composition of the complex was Co(HBI )2(LI )2 with a cis‐form octahedron geometry structure. Both intra and intermolecular hydrogen bonding between the uncoordinated carbonyl oxygen atom of the deprotonated monodentate anionic ligand LI and the hydrogen atom of the α‐hydroxy or the oxime hydroxyl group of HBI were observed in the crystal lattice. In order to bridge the gap between the solid‐state structure of the cobalt(II ) synergist complex and the solution structure of the extracted cobalt(II ) complex with the actual synergistic mixture containing Versatic10 and Lix63 in the nonpolar organic phase, both the cobalt(II ) synergistic complex and the extracted cobalt(II ) complex were further investigated by Fourier transform infrared spectroscopy (FT‐IR ) and electrospray ionization mass spectrometry (ESI‐MS ). The results indicated that the extracted cobalt(II ) complex in the nonpolar organic phase might possess a similar coordination structure as that of the cobalt(II ) synergist complex. 相似文献
996.
《中国化学会会志》2017,64(9):1104-1110
A new unsymmetrical tridentate NNS Schiff base ligand, 2‐(2‐nitrophenylthio)‐N‐((pyridine‐2‐yl)methylene)benzenamine (L), and its Mn(II ), Ni(II ), Cu(II ), and Zn(II ) complexes were synthesized. These compounds were characterized by different physicochemical and spectroscopic techniques. The molecular structure of [NiL2 ](ClO4 )2 was determined by single‐crystal X‐ray diffraction. In this complex, two ligands coordinate through azomethine‐N, pyridine‐N, and thioether‐S, forming a mononuclear 6‐coordinate distorted octahedral geometry about a nickel. 相似文献
997.
《Helvetica chimica acta》2017,100(4)
[K(crypt‐222)]+ ( 1 ) and [K(crypt‐222)]+ ( 3 ) are isostructural, displaying nearly identical unit cell parameters. The two structures are similar to the extent that the previously reported [K(crypt‐222)]+ model can be refined against the new data for [K(crypt‐222)]+ , with extra electron density being observed from the fourth fluorine atom of the . In agreement with experimental observations, theoretical calculations suggest that deprotonated [K(crypt‐222)]+ is highly unstable even at as low as 195 K. The previously considered 1:1 CHF 3 clathrate of deprotonated [K(crypt‐222)]+ (crystallographically indistinguishable from 1 ) is ruled out on the basis of all available data. 相似文献
998.
About the compatibility between ansatzes and constraints for a local formulation of orbital‐free density functional theory 下载免费PDF全文
Functional properties that are exact for the Hohenberg–Kohn functional may turn into mutually exclusive constraints at a given level of ansatz. This is exemplarily shown for the local density approximation. Nevertheless, it is possible to reach exactly the Kohn–Sham data from an orbital‐free density functional framework based on simple one‐point functionals by starting from the Levy–Perdew–Sahni formulation. The energy value is obtained from the density‐potential pair, and therefore does not refer to the functional dependence of the potential expression. Consequently, the potential expression can be obtained from any suitable model and is not required to follow proper scaling behavior. 相似文献
999.
1000.
An array of 2-substituted-4,5-diphenyloxazoles were found to be cleaved to triacylamines and diacylamines (imides) using a reagent system composed of m-chloroperbenzoic acid (MCPBA) and 2,2′-bipyridinium chlorochromate (BPCC). The 2-alkyl-4,5-diphenyloxazoles give imides (38–60%) as the predominant cleavage product while the 2-aryl-4,5-diphenyloxazoles give triacylamines (44–71%). Two mechanisms involving intermediates such as cyclic endoperoxides or oxachromacycles were proposed. An application of the oxidative cleavage to the multi-step synthesis of (±)-phoracantholide I seco acid is detailed. 相似文献