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41.
O. I. Artyushin E. V. Sharova I. L. Odinets S. V. Lenevich V. P. Morgalyuk I. G. Tananaev G. V. Pribylova G. V. Myasoedova T. A. Mastryukova B. F. Myasoedov 《Russian Chemical Bulletin》2004,53(11):2499-2507
An efficient method for the synthesis of secondary alkylamides of phosphorylacetic acids (APA) was proposed. The method involves amidation of ethyl phosphorylacetates with primary aliphatic amines. The scope of reaction was determined. Reactions with ethylenediamine and 1,4-diaminobutane yield the corresponding bisamides; in the case of 1,3-diaminopropane, N-(3-aminopropyl)diphenylphosphorylacetamide or N,N-propylenebis(diphenylphosphorylacetamide) was obtained, depending on the reaction conditions. The extraction of americium(III) complexes and the sorption of uranium(VI) by sorbents with physically sorbed APA from nitric acid solutions were studied. There is no correlation between the partition coefficient of americium(III) and the structure of APA; in the sorption of uranium(VI), the degree of extraction depends on the complexone structure.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2394–2402, November, 2004. 相似文献
42.
Reduction of enantiopure N-p-toluenesulfinyl ketimines derived from 2-pyridyl ketones affords N-p-toluenesulfinyl amines with good yields and diastereoselectivities. 相似文献
43.
44.
Martina Nveke Peter G. Jones Armand Blaschette Dietmar Schomburg Heiko K. Cammenga Matthias Epple 《无机化学与普通化学杂志》1993,619(6):1027-1036
Polysulfonyl Amines. XLI. A Silver(I) Hydrate with an Unusual Composition: Characterization of Tetrakis(dimesylamido)aquatetrasilver(I) [Ag4(N)SO2CH3)2}4(H2O)] by X-Ray Diffraction and Thermal Analysis The title compound is obtained by crystallizing AgN(SO2CH3)2 from water at room temperature. Crystallographic data (at ?95°C): Triclinic space group P1 , a = 864.6(4), b = 1 211.2(5), c = 1 399.1(5) pm, α = 90.97(3), β = 90.90(3), γ = 98.25(4)°, V = 1.4496 nm3, Z = 2, Dx = 2.608 Mg m?3. The four independent silver atoms and the water molecule form zigzag chains Ag(1)-Ag(2)-(μ-H2O)-Ag(3) …? Ag(4) …? Ag(1′) with distances Ag(1)-Ag(2) 309.7, Ag(2)-O(w) 241.8, O(w)-Ag(3) 241.4, Ag(3) …? Ag(4) 342.9, Ag(4) …? Ag(1′) 361.4 pm. The catenated silver atoms are further connected by the dimesylamide anions acting as tridentate bridging (α-O, N, ω-O)-ligands. The resulting strands are interconnected into layers through one O(S)-Ag′ contact (247 pm) and one hydrogen bond O(w)-H(l) …? O′(S) per repeating unit. Between the layers, a weak O(S) …? Ag″ interaction (271 ptn) and a hydrogen bond O(w)-H(2) …? O(S) per repeating unit are observed. The silver atoms Ag(l) to Ag(4) display the coordination numbers 5 [NO,Ag(2), distorted trigonal bipyramid], 5[NO2,O(w)Ag(I), distorted trigonal bipyramid], 5[O4,O(w), trigonal bipyramid], and 2 + 1 (N2, li-near; plus a secondary Ag …? 0 contact). The dehydration of the title compound and a solid-solid phase transformation in anhydrous AgN(SO2CH3)2, were quantitatively investigated by thermoconductometry and time- and temperature-resolved X-ray diffractometry (TXRD). 相似文献
45.
In developing a method for possible low level isotopic enrichment, which uses to advantage the equilibrium isotope effect
observed during U(1V)-U(VI) electron exchange reaction in sulphate solutions, details of a solvent extraction process involving
high concentration of a mixture of U(IV) and U(VI) and at low acid concentrations, are described. The extraction behaviour
of uranium under these conditions is discussed. During the extraction with amines, U(IV) tended to get oxidised in sulphate
solutions. 相似文献
46.
Citrus aurantium L. (Rutaceae) fruit extracts have recently been used for weight loss. Among the adrenergic amines the most important active constituent is the sympathomimetic compound synephrine and commercially available extracts are standardized for their content of this active principle. A capillary electrophoresis method was developed for the quantitative and qualitative determination of d-synephrine, l-synephrine, d-octopamine, l-octopamine, tyramine, n-methyl tyramine and hordenine. The electrophoretic separation was performed using a 75 cm × 50 µm ID (66.5 cm effective length) fused silica capillary. The samples were injected by pressure for 5s at 50 mbar and the running voltage was 30 kV at the injector end of the capillary. The method developed was successively applied to the determination of the adrenergic amines in dietary supplements, in various Citrus species including Citrus aurantium, jams and juices. Synephrine was the main component and present in the levels from 0.02–0.17% in various Citrus species and 0.42–69.28 mg in dietary supplements claiming to contain Citrus aurantium. Parameters affecting the resolution between (+) and (−)-enantiomers, such as pH, cyclodextrin concentration, temperature, organic modifier, buffer concentration and capillary dimensions were reported. 相似文献
47.
Ring opening in 2-alkyl-4,5-dihydrooxazoles by the action of azoles gave intermediate N-(2-azolylethyl)alkanamides, whose hydrolysis afforded N-(2-aminoethyl)azoles.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1781–1784, October, 2006. 相似文献
48.
α-Halogeno ethers, sulfides, and amines are reactive compounds which can be used for the formation of new C? C bonds, either as nucleophilic or as electrophilic reagents, or by α-elimination. The use of these compounds in the synthesis of many classes of organic compounds is reviewed. 相似文献
49.
O. I. Dyubchenko V. V. Nikulina E. I. Terakh A. E. Prosenko I. A. Grigor’ev 《Russian Chemical Bulletin》2007,56(6):1149-1155
The reaction of ω-(4-hydroxyaryl)haloalkanes with various nitrogen-containing agents afforded primary, secondary, and tertiary
amino derivatives of 2,6-dialkylphenols. For the compounds synthesized, the reaction rate constants with peroxide radicals
were measured for cumene and methyl oleate oxidation. The total inhibitory activity in the model reactions of thermal autooxidation
of lard and hexadecane was studied. The rate constants of alkyl(hydroxylaryl)amines are the same as those of the corresponding
alkylphenols, whereas the total inhibitory activity of some alkyl(hydroxylaryl)amines exceeds substantially that for alkylphenols.
Dedicated to the memory of Academician N. N. Vorozhtsov on the 100th anniversary of his birth.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1107–1112, June, 2007. 相似文献
50.
E. P. Serebryakov A. G. Nigmatov M. A. Shcherbakov M. I. Struchkova 《Russian Chemical Bulletin》1998,47(1):82-90
In the amine-catalyzed reactions of prenal with (Z)-5-methyl-2-(methoxycarbonyl)hexa-2,4-dienoic or (Z)-3-phenyl-2-(ethoxycarbonyl)prop-2-enoic acid chiral β-amino alcohols provide for higher enantiomeric purity of the resulting
alkyl 4-methyl-6-(2-methylprop-1-enyl)-and 4-methyl-6-phenylcyclohexa-1,3-dienoates than that provided by related chiral amines
without hydroxy group. The values ofee attained in nonpolar solvents are higher than those observed in the polar ones. Substituting stoichiometric amounts of a
chiral 1-amino-3-methylbuta-1,3-diene for a combination of prenal with 0.1 equiv. of the corresponding chiral amine results
in the products of much lower enantiomeric purity.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 84–92, January, 1998. 相似文献