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Raman spectra (4000-150 cm?1) of a single crystal of NaGa(NH2)4 and infrared spectra (4000-200 cm?1 ) of a polycrystalline sample have been studied at different temperatures. An assignment of the bands is given. The spectra are discussed assuming S4 and Td point group symmetry of the Ga(NH2)?4 ion at low temperature and at room temperature respectively. Metal-ligand and N-H stretching frequencies are compared to those of some other amido metalates. 相似文献
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The total synthesis of a prostaglandin endoperoxyde analogue in which the upper side chain is attached to a nitrogen atom, is presented. 相似文献
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To obtain the intrinsic acidity constant of a carboxylic ion-exchanger, we propose a method of graphical double extrapolation. The results for an ion-exchanger made of polyvinyl alcohol grafted with acrylic acid are close to those published for the corresponding linear polyacid. 相似文献
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M.T. Averbuch-Pouchot 《Journal of solid state chemistry》1982,41(3):262-265
The iodato-sulfate K4H2(S2I2O14) is monoclinic, with a unit cell: a = 13.84(1) Å, b = 7.173(5) Å, c = 7.443(5) Å, β = 93.16(1)°, and Z = 2. The crystal structure of this salt has been solved using 1956 independent reflections, with a final R value of 0.03. The main feature of this salt is the existence of a finite new heteropolyanion: (I2S2O14)?6. 相似文献
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Luc Morin Daniel Barillier Marie-Paule Strobel Daniel Paquer 《Tetrahedron letters》1981,22(24):2267-2268
Ozone reacts with one vinyl sulphide and gives an oxirane, this fact confirms that oxirane is probably an intermediate in course of reactions of ozone with vinyl derivatives which give products containing unmodified hydrocarbon chains. 相似文献
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Bis(methyl)disulphide and the organometallic compound {(Cp)Mo(CO)3}2 in low oxidation state under photolysis give especially with the hexa-fluorobut-2 yne a 18-electron olefin complexe {(Cp)Mo(CO)3(CF3C2CF3SCH3)}. The new compounds are reported and the reaction discussed. 相似文献
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M Zeches T Ravao B Richard C Massiot L.Le Men-Olivier J Guilhem C Pascard 《Tetrahedron letters》1984,25(6):659-662
The relative configuration of echitamidine is established by spectral and X-ray crystallographic techniques. Three other isomers are described and a structure is proposed for them. 相似文献
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After a general survey of the relations, proposed by several authors, to calculate the mean dielectric permittivity of a mixture versus the volume concentration and the permitivity of the components, we propose a formula and charts deduced from it. Experimental measures have been made on polystyrene-based mixtures and allow the checking of this formula. 相似文献
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The reaction of 1,3,5-trinitrobenzene (TNB) with imidazolide ion (Im-) provides the first example of the ambifunctional nucleophilic reactivity of this anion towards an aromatic electrophile. The N-adduct is formed under kinetic control but the C-adduct is the thermodynamically stable product. The N,C-diadduct is also observed. 相似文献
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During the Michael addition of chiral α-sulfinyl eser (+) on αβ-unsaturated esters, an extent of 24% of asymmetric induction was observed. It is shown that the addition products can be transformed into optically active δ-lactones. 相似文献