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841.
V. A. Yanchenko A. M. Demchenko M. O. Lozinskii 《Chemistry of Heterocyclic Compounds》2004,40(4):516-518
We propose a method for obtaining derivatives of 7H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazine by alkylation of 4-amino-5-methyl-4H-1,2,4-triazole-3-thiol by substituted -chloroacetanilides, followed by cyclization of the intermediate by phosphorus oxychloride. 相似文献
842.
Rodolphe Clérac Dieter Fenske Ibrahim Issac Alexander Rothenberger 《Journal of Cluster Science》2004,15(2):189-198
Two Fe–Ta containing sulfido complexes were prepared by the reaction of the metal halide salts with bis-trimethylsilylsulfide in the presence of PMe3. The complexes demonstrate that coordination chemistry with iron sulfides can give access to a range of heterometallic complexes. In [Cl(Me3P)Ta(
2-S)2(
3-S)Fe(PMe3)2]2 the two [Cl(Me3P)Ta] units are arranged around one central Fe2(
2-S)2 unit. In [(Me3P)4(MeCN)2FeII]2+[(Me3P)2TaIVFeII
3(
3-S)4Br4]2– a [TaFe3S4]2+ cuboidal arrangement was observed. The complex salt forms a polymeric structure in the solid-state with weak H-bonds between the ions. The [(Me3P)2TaIVFeII
3(
3-S)4Br4]2– ion was characterised by magnetic measurements showing strong antiferromagnetic interactions between the metal centres. 相似文献
843.
Luigi Ambrosone Lucia Costantino Gerardino D'errico Vincenzo Vitagliano 《Journal of colloid and interface science》1997,190(2):286
The densities and viscosities of binary aqueous mixtures of poly(ethylenoxide)hexanols [C6H13(OCH2CH2)mOH, C6Em] (m= 3, 4, and 5) have been studied in the micellar composition range. For the same surfactants the self-diffusion coefficients in mixtures with heavy water have been determined by the spin-echo pulsed field gradient method. The volumetric data are interpreted by means of the phase separation model, and values of the CMC, volume change, and standard free energy change of micellization are obtained. From the viscosity data the hydration numbers of the surfactant hydrophilic head in the micellar state are computed; they are in agreement with those obtained from HDO self-diffusion data. The surfactant self-diffusion data are used to calculate the apparent micelle radius and the aggregation number. The micellization parameters obtained for the different surfactants are compared and discussed. 相似文献
844.
LI Yan-Tuan LIAO Dai-Zheng JIANG Zong-Hui WANG Geng-LinDepartment of Chemistry Nankai University Tianjin China 《中国化学》1995,(3)
Six novel μ-oxamido heterobinuclear complexes, namely Cu(oxae)Ln(Me2bpy)2-(ClO4)3 (Ln=La, Nd, Gd, Tb, Ho, Er), where oxae denotes N, N'-bis(2-aminoethyl)oxamido dian-ion, Me2bpy is 4,4'-dimethyl-2,2'-bipyridyl, have been synthesized and characterized by elemental analyses, IR, conductivity measurements and electronic spectra. The temperature dependence of the magnetic susceptibility of Cu(oxae)Gd(Me2bpy)2(ClO4)3 has been meaured over the range 4-300 K. The least-squares fit of the experimental susceptibilities yielded J - 1.87 cm-1.The observed Gd(Ⅲ)-Cu(Ⅱ) coupling is ferromagnetic. One plausible mechanism that can cause a ferromagnetic coupling between Gd(Ⅲ) and Cu(Ⅱ) is discussed in terms of spin-polarization. 相似文献
845.
A. V. Kazakova N. D. Kushch L. I. Buravov E. B. Yagubskii S. V. Simonov L. V. Zorina S. S. Khasanov R. P. Shibaeva E. Canadell J. Yamada M. Umemiya 《Russian Chemical Bulletin》2007,56(1):49-55
New radical cation salts based on 2,5-bis(1,3-dithian-2-ylidene)-1,3,4,6-tetrathiapentalene (BDA-TTP) with copper(II) metal complex anions, β-(BDA-TTP)4Cu2Cl6 and (BDA-TTP)2CuCl4, were synthesized and structurally characterized. Single crystals were prepared by electrochemical oxidation of BDA-TTP under
galvanostatic conditions. X-ray diffraction study demonstrated that the salts have a layered structure, in which the conducting
BDA-TTP layers alternate with the [Cu2Cl6]2− or [CuCl4]2− anions. Both salts show the semiconductor-type temperature dependence of the conductivity.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 48–54, January, 2007. 相似文献
846.
以(S)-2-氨基丙醇为手性源与α-溴-3-氯苯丙酮反应, (R)-2-氨基丙醇为手性源与6-甲氧基-2-(2-溴丙酰基)萘反应, 分别合成了手性纯化合物(2R,3R,5S)-3,5-二甲基-2-(3-氯苯基)-2-吗啉醇盐酸盐(4a)和(2S,3S,5R)-3,5-二甲基-2-(6-甲氧基-2-萘基)-2-吗啉醇盐酸盐(4b), 利用X射线单晶衍射仪测定了两化合物的晶体结构和两化合物的空间结构, 并初步分析两化合物空间结构, 化合物4a晶体属正交晶系, 空间群为P21212, 晶胞参数为: a=0.8718(2) nm, b=0.7883(2) nm, c=2.0247(6) nm, Z=4, V=1.3915(7) nm3, Dc=1.328 g/cm3, F(000)=584, R1=0.0399, wR2=0.0797, S=1.042. 化合物4b晶体属正交晶系, 空间群为P212121, 晶胞参数为: a=0.71035 (9) nm, b=0.77703(10) nm, c=2.9820(4) nm, Z=4, V=1.6318(4) nm3, Dc=1.318 g/cm3, F(000)=688, R1=0.0520, wR2=0.1108, S=0.994. 相似文献
847.
The reactions of substituted 3-cyanopyridine-2(1H)-thiones and 3-cyano-2-(methylthio)pyridines with lithium aluminum hydride in anhydrous diethyl ether afforded the corresponding 3-aminomethyl derivatives, which were used in the synthesis of the corresponding amides. 相似文献
848.
Tian-Fu LiuHua-Kuan Lin Shou-Rong ZhuZhong-Ming Wang Hong-gen WangHong-Wei Sun Xue-Bing LengYun-Ti Chen 《Journal of Molecular Structure》2002,605(1):117-122
The Mn(II) and Zn(II) complexes of N,N′-diisopropyl-1,10-phenanthroline-2,9-dimethanamine have been synthesised, and the structure of the two complexes have been studied by X-ray crystallography. 相似文献
849.
N-[2(3)-Hydroxyalkylj-4-thiazolidinones have been synthesized by the reaction of 2(3)-vinyloxyalkylamines with mercaptoacetic acid in 24–69 % yield. The structure of the compounds obtained was supported by (R and1H NMR spectroscopic data.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 677–679, March, 1996. 相似文献
850.
Hiromu Hayashi 《Catalysis Surveys from Japan》1999,3(1):43-52
Additive telluromolybdates, MoO3·2TeO2 and MIIO·TeO2·MoO3 (MIITeMoO6; MII = Co, Mn, Zn), converted ethyl lactate selectively to pyruvate in a vaporphase fixedbed flow system at 250–300 °C. A synergy in activity was observed for binary TeO2–MoO3, and crystalline Te2MoO7 was suggested as the active species. The Rietveld analysis of powder XRD patterns of ternary CoTeMoO6 revealed the layer structure quite different from that of the reference Te2MoO7, but tellurium was again located adjacent to molybdenum linked through lattice oxygen. 相似文献