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991.
Prolonged heating of (CH3NPF3)2 in a sealed tube at 120°C yields (CH3N)4P3F7 and PF5. Under the experimental conditions these compounds react to (CH3N)4P3F6 +PF6 . Reaction of (CH3NPF3)2 in the presence of PF5 leads to a marked decrease in the formation of the ionic compound. The influence of the fluoride donating saltsMF (M=Li, Na, K, Cs) is investigated.

Mit 1 Abbildung

Früher: Alkyliminophosphorsäuretrihalogenide, 1. und 2. Mitt.  相似文献   
992.
Allyl sulfur compounds play a major role in the chemoprevention against carcinogenesis. The present study compared the antiproliferative effects of diallyl sulfide (DAS), diallyl disulfide (DADS) and garlic extract on p53-wild type H460 and p53-null type H1299 non small cell lung cancer cells (NSCLC). The DAS and DADS treatment of both H460 and H1299 cells resulted in the highest numbers of cells in apoptotic state as measured by acridine orange staining, however, garlic extract treatment did not induce any significant apoptotic cells by MTT assay. DADS was found to be more effective in inducing apoptosis on NSCLC. The level of p53 protein in H460 cell was increased following DADS treatment. DAS and garlic extract treatment of H460 cells induced a rise in the level of Bax and a fall of Bcl-2 level. These results demonstrate that DAS, DADS and garlic extract are effective in reduction of anti-proliferative gene in NSCLC and suggest that modulation of apoptosis-associated cellular proteins by DAS, DADS and garlic extract may be the mechanism for apoptosis which merit further investigation as potential chemoprevention agents.  相似文献   
993.
Thioaroylketene S,N-acetals were treated with active methylene compounds including beta-keto ester, nitromethane, cyanoacetic acid, p-toluenesulfonylacetone, 4-nitrophenylacetic acid, and diethyl (2-oxopropyl)phosphonate in the presence of mercury(II) acetate in CH(2)Cl(2) at room temperature. These reactions gave 3-alkylamino-5-arylthiophenes containing various substituents, which comprised, respectively, alkoxycarbonyl, nitro, cyano, p-toluenesulfonyl, 4-nitrophenyl, and diethylphosphono groups at C-2 in good yields. The reaction of 3-methylamino-3-methylthio-1-phenylthioxopropene with malonic acid or Meldrum's acid under the same conditions gave 3-methylamino-5-phenylthiophene. Similarly, treatment of 3-methylamino-3-methylthio-1-phenylthioxopropene with various enolizable cyclic ketones such as 4-hydroxy-6-methyl-2-pyrone, homophthalic anhydride, 2-hydroxy-1,4-benzoquinone, and 1, 3-diethyl-2-thiobarbituric acid gave thieno[3,2-b]pyridin-4-one, thieno[3,2-c]isoquinolin-5-one, thieno[3,2-c]benzazepine-1,6-dione, and thieno[3,2-d]pyrimidine-2,4-dione, respectively.  相似文献   
994.
The kinetics of cation exchange reaction of Eu(III) propylenediaminetetraacetate with Yb(III) has been studied in an aqueous solution by the polarographic procedure. The measurements were made at 25°C and at an ionic strength of 0.5 M KCl. The dissociation of the europium complex has been found to be catalyzed by hydrogen ions. The influences of the inductive effect and the steric hindrance of a C-methyl group on the ethylene of PDTA are discussed by comparing it to analogous EDTA and CyDTA system.  相似文献   
995.
The reaction of N-(2-pyridyl)-carbaminates (3), 1-phenyl-3-(2-pyridyl)-urea (5 a) or alkyl and aryl substituted pyridopyrimidinediones (2) synthesized from 2-amino-pyridine with arylisocyanates (4 a, b) yields 3-aryl substituted pyrido-[1,2-a]-s-triazine-2,4-diones (1). 2-Aminopyridine and azamalonic derivatives (ethoxycarbonyl isocyanate, ethyl iminodicarboxylate) react to give the 3-unsubstituted triazine system (1 c). The isolation of monocyclic triazinediones obtained from the reaction of N-phenylbenzamidine (9) with aryl isocyanate (4 a) or ethoxycarbonyl isocyanate failed because of hydrolytic ring opening. The mechanism of the reaction of 3-substituted pyrido-pyrimidinediones (2) and phenyl isocyanate (4 a) is discussed.  相似文献   
996.
The molecular structure of norbornene has been investigated in the gas phase by combining electron diffraction data with microwave spectroscopic rotational constants. The interatomic distances (rg) and bond angles were obtained by applying a least squares program to the refined experimental molecular diffraction intensities. The CC bond length was found to be 1.336 ± 0.002 Å while the
) bond length was 1. 529 ± 0.007 Å. Other bond lengths and angles included (IUPAC numbering system was used for norbornene): C1-C6 = 1.550 ± 0.020 Å, C1-C7 = 1.566± 0.005 Å, C5-C6 = 1.556 ± 0.005 Å, C-Have. = 1.103 ± 0.003 Å, ∠C1C2C4 = 95.3°. The dihedral angle between planes C1C2C3C4 and C1C6C5C4 is 110.8 ± 1.5° while that between C1C2C3C4 and C1C7C4 is 122.3°. The moments of inertia calculated from ED structure are in good agreement with microwave spectroscopic values.  相似文献   
997.
The electrochemical stability of 10 organic cations, which can be used in ionic liquids (IL), was investigated as solutes in acetonitrile (ACN). The stability of three of the salts, BenMe2EtNCl (salt III), 1-butyl-2-methyl pyrrolidium chloride (salt VI), and its structural isomer, BuMe2ProNCl (salt VII), were also compared in chloroaluminate ILs. The chloroaluminate ILs of salts VI and VII are investigated for the first time. The NaCl-neutralized ILs of salts VI and VII have melting points of 43.2 and 3.7 degrees C, respectively. The benzyl-substituted cation, salt III, was more easily reduced in ACN or as the neutral chloroaluminate IL than the alkyl-substituted cation, salt VII, due to the better leaving ability of the benzyl group. Mass spectroscopy measurements before and after electrolysis on the benzyl-substituted solutions confirmed that reduction involves the loss of an alkyl group. In ACN, salt VI was found to be the most difficult to reduce (1 mA/cm2 at -2.09 V) due to its cyclic structure. However, in the chloroaluminate IL, the pyrrolidinium cation was more easily reduced than salt III or its isomer, salt VII, resulting in an insoluble black deposit. This is consistent with the mass spectrometry data, which do not show formation of low-molecular-weight products, as in the reduction of salts III and VII. The IL of salt VII was the most stable in the presence of sodium. Sodium ions could be reduced and reoxidized with a maximum Coulombic efficiency of 94.1% versus 87.2% for salt VI. Reduction of the pyrrolidinium cation produces insoluble products, most likely through opening of the cyclic ring, and an inferior medium for sodium ion reduction compared to the benzyl- and butyl-substituted cations, even though reduction of the cation occurs at a more negative potential in acetonitrile.  相似文献   
998.
Although a lithium metal anode has a high energy density compared with a carbon insertion anode, the poor rechargeability prevents the practical use of anode materials. A lithium electrode coated with Li2CO3 was prepared as a negative electrode to enhance cycleability through the control of the solid electrolyte interface (SEI) layer formation in Li secondary batteries. The electrochemical characteristics of the SEI layer were examined using chronopotentiometry (CP) and impedance spectroscopy. The Li2CO3-SEI layer prevents electrolyte decomposition reaction and has low interface resistance. In addition, the lithium ion diffusion in the SEI layer of the uncoated and the Li2CO3-coated electrode was evaluated using chronoamperometry (CA).  相似文献   
999.
The novel atrane-like six-coordinate (RO)(2)TaL complexes [where R = Me or Et and L = tris(2-oxy-3,5-dimethylbenzyl)amine] containing three six-membered rings have been synthesized and characterized. The R = Me complex is the first group 5 representative of this class of compounds structurally characterized by X-ray means. Somewhat surprisingly, these compounds failed to function as single-site initiators for the polymerization of l-LA to isotactic PLA and rac-LA to atactic PLA, whereas Ta(OEt)(5) and two titanium analogues ROTiL (where R = 2,6-di-i-PrC(6)H(3) and i-Pr) as well as Ti(O-i-Pr)(4) were effective catalysts for both polymerizations.  相似文献   
1000.
Copper oxide was incorporated into MCM‐41 by a one‐pot synthesis under acidic conditions to prepare a new mesoporous nitrosamines trap for protection of the environment. The resulting composites were characterized by XRD, N2 adsorption–desorption, and H2 temperature‐programmed reduction techniques, and their adsorption capabilities were assessed in the gaseous adsorption of N‐nitrosopyrrolidine (NPYR). The adsorption isotherms were consistent with the Freundlich equation. The copper salt was deposited onto MCM‐41 during the evaporation stage and was fixed on the host in the calcination process that followed. MCM‐41 was able to capture NPYR in air below 373 K but not at 453 K. Loading of copper oxide on MCM‐41 greatly improved its adsorption capability at elevated temperatures. The influence of the incorporation of copper into MCM‐41 samples and the adsorption behavior of these samples are discussed in detail.  相似文献   
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