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1.
2.
The powder of LiNi1/3Co1/3Mn1/3O2 were prepared directly without artificial grinding and washing by a eutectic molten-salt mixture (0.38LiOH·H2O-0.62LiNO3) method. According to this method, the eutectic molten-salt mixture was self-mixed with precursor thoroughly at low temperature, and then sintered at a certain temperature. The tap-density of the powder obtained was 2.87 g·cm-3. The well-layered 琢-NaFeO2 structure and regular morphology were confirmed by X-ray diffraction (XRD) and scanning electronmicroscopy (SEM).XPSstudies showed that the predominant oxidation states of Ni, Co, andMn in the compound were 2+, 3+, and 4+, respectively. Cathodic behaviour was examined by charge-discharge cycling. The synthesized powder showed a reversible capacity of 160 mAh·g -1 at a specific current of 0.2C in the rang 3.0-4.3 V up to 50 cycles without noticeable capacity-fading.  相似文献   

3.
Indole-3-methylamine (1) has been well demonstrated to be a very useful intermediate as a pharmaceutical building block and starting material for syntheses of phytoalexins.[1] The instability of indole-3-methylamine (1) has undoubtedly restricted its application in synthetic chemistry. Hofmann rearrangement that directly converts carboxamides to alky carbamates in the presence of alcohol required unexceptionally a strong base,[2] which devaluated the possible usefulness of Hofmann rearrangement in preparation of base sensitive amines, especially for the preparation of unstable indole-3-methylamine (1). Herein we would like to report a convenient method for the preparation of alkyl carbamates of 1-protected indole-3-methylamines (4) via the diacetoxyiodobenzene (DIB) promoted Hofmann rearrangement under neutral condition.  相似文献   

4.
(E)-α-Iodovinyl sulfides 1 underwent the Sonogashira coupling reactions with terminal alkynes 2 in piperidine at room temperature in the presence of 5 mol % of Pd(PPh3)4 and 10 mol % of CuI to afford the corresponding 1, 3-enynylsulfides 3 stereospecifically in high yields.  相似文献   

5.
<正> Introduction. Previously, we have reported the compound α-(Et_4N)_3[Fe_3(SPh)_3-Br_3Cl_3](Ⅰ)~1 with C_2 symmetry. An isomer(Ⅱ) of this compound, which has D_3dsymmetry, is reported in this paper. Brow-green crystals of Ⅱ is obtained from the reaction of FeCl_2, PhSNa and Et_4NBr (1:1:1) in acetonitrile solution.  相似文献   

6.
A series of novel 3-bromo-1-(3-chloropyridin-2-yl)-N-hydroxy-N-aryl-lH-pyrazole-5-carboxamides was synthesized by the reaction of pyrazole carbonyl chloride with each of substituted phenylhydroxyamines. The latter ones were prepared in good yields by reducing substituted nitrobenzene compounds with Zn/NH4CI reductant system in alcohol. Structures of the title compounds were determined by IR, 1H NMR, and HRMS. Their insecticidal and fungicidal activities were evaluated by larvicidal test against oriental armyworm and the mycelium growth rate method, respectively.  相似文献   

7.
A convenient and highly efficient conversion of 1β-OH-trans-vitamin D3, a main byproduct in synthesis of active vitamin D3, to 1α-OH-trans-vitamin D3 is reported. The conversion could be accomplished in 1 minute with 90% yield.  相似文献   

8.
The cationic polymerizations of 1, 3-pentadiene were initiated by AlCl_3 in n-hexaneat 30℃ in the presence of alkyl halides, i.e., tert-butyl chloride, tert-butyl bromide andisobutyl chloride. The effects of these halides on the polymer yield, molecular weight,crosslinking reaction, cyclization and polymer microstructure, have been investigated. Twomain side reactions, crosslinking and cyclization, were suppressed and reduced by theaddition of the halides. The proportion of 1, 4 units of polymer chains was increasedby the presence of the halides, which reduced the polymer yield and the molecular weightof polymers.  相似文献   

9.
A series of CoxMgxO/Al2O3/FeCrAl catalysts (x=0-1) were prepared. The structures of the catalysts were characterized using XRD, SEM, and TPR analyses. The catalytic activity of the catalysts for methane combustion was evaluated in a continuous flow microreactor. The results indicated that the active washcoats adhered well on the FeCrAl foils. The phases in the catalysts were Co--xMgxO solid solutions, α-Al2O3, and γ-Al2O3. The surface particle size of the catalysts varied with variations in the molar ratios of Co to Mg. The Co component of the Co1_xMgxO/Al2O3/FeCrAl catalysts played an important role in the catalytic activity for methane combustion. In the Co1-xMgxO/AluO3/FeCrAl series catalyst (x=0.2-0.8), the catalytic activity in terms of x was in the order of 0.5〉0.2〉0.8 under the experimental conditions. The presence of Mg in these catalysts could promote the thermal stability to a large extent. There were strong interactions between the Co1-xMgxO oxides and the AluO3/FeCrAl supports.  相似文献   

10.
The reaction of a series of 1-(3-pyridyl)-2,2-di-substituted ethylenes with 1-benzyl-1,4-dihydronicotinamide (BNAH) in deaerated acetonitrile produces the corresponding 1-(3-pyridyl)-2,2-di-substituted ethanes in contrast to benzylidenemalononitrile (BM) which does not react with BNAH under the same conditions.  相似文献   

11.
The approaches to synthesis of 1-phenyl-1-halo-1-silacyclohexanes C5H10Si(Ph)X (X = F, Cl, Br) have been examined. 1-Phenyl-1-chloro-1-silacyclohexane has been prepared via the known reaction of phenyltrichlorosilane with dimagnesium derivative of 1,5-dibromopentane; up to 20% of 1-bromo-1-phenyl-1-silacyclohexane admixture is formed along with the target product. The minor product formation has been prevented using an alternative method of chlorination of 1-phenyl-1-silacyclohexane with N-chlorosuccinimide. 1-Phenyl-1-fluoro-1-silacyclohexane has been obtained in close to quantitative yield via the reaction of 1-phenyl-1-chloro-1-silacyclohexane with SbF3 and in 70% yield via its reaction with HF. The synthesis of 1-phenyl-1-bromo-1-silacyclohexane via bromination of 1-phenyl-1-chloro-1-silacyclohexane with N-bromosuccinimide has given the target product as a minor one, the major product being disiloxane formed due to hydrolysis of the Si–Br bond.  相似文献   

12.
New synthetic routes to 1-methyl-1-silaindane (1b) and 1-methyl-1-germaindane (1b) were developed and the desired products were obtained in good isolated yield. Compounds 1a and 1b were fully characterized by mass spectroscopy, 1H and 13C{1H} NMR, and infrared spectroscopy.  相似文献   

13.
用pH电位法研究了1-乙酰胺基丙叉-1,1-二膦酸(S-186)和1-丙酰胺基乙叉-1,1-二膦酸(S-106)与碱土金属的螯合作用(30±O.1℃).当金属离子与配体的摩尔浓度比为10∶1、1∶1和1∶2时,在水溶液中形成了MHL、ML、ML_2和M_2L等几种类型的配合物.分别测定了它们的稳定常数,其中S-186配合物稍高于S-106,说明配合物稳定性与螯合剂的碱度有平行关系.值得注意的是,这两种螯合剂与Sr~(2 )形成的双核配合物的稳定性均较其它碱土金属离子的为高.  相似文献   

14.
1, 1-Difluorocyclopropa[a]naphthalene ( 1b ) is prepared in three steps from 4-bromo-1,2-dihydronaphthalene ( 7 ) via carbene addition, benzylic bromination and bidehydrohalogenation. Structural evidence for formation of 1b is based on 1H- and 19F-NMR spectroscopy. Compound 1b is stable in solution at ?30°. Upon reaction with MeOH/H+ it is converted to a 1:2 mixture of 1- and 2-methylnaphthoate ( 10 and 11 , respectively).  相似文献   

15.
High molecular weight, 1:1 alternating copolymers of 1-bicyclobutanecarbonitrile with styrene were prepared in tetramethylenesulfone solution by complexing the electron-poor bicyclobutane monomer with zinc chloride. Methyl 1-bicyclobutanecarboxylate under these conditions gave copolymers containing a slight excess of styrene units (ratio 1:1.3 to 1:1.8). High molecular weight homopolymers of 1-bicyclobutanecarbonitrile and of methyl 1-bicyclobutanecarboxylate were prepared similarly. The tendency of the bicyclobutane nitrile to form 1:1 alternating copolymers is as great as that of its vinyl analog, acrylonitrile, and the synthesis of other alternating copolymers from this monomer should be possible.  相似文献   

16.
《Tetrahedron letters》1987,28(24):2693-2696
The title compounds are prepared by reaction of disubstituted diazomethanes with 1-chloro-2-phenyl-2-trimethylsilyl-1-phosphaalkene. The chemistry of the 1-chloro-1-phosphiranes is described.  相似文献   

17.
Conclusions The synthesis of some nuclear-substituted derivatives of 1-phenyl-1-methyl-1-silacyclobutane by the reaction of 1-methyl-1-chloro-1-silacyclobutane with the appropriate arylmagnesium bromides was described.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1686–1688, July, 1978.  相似文献   

18.
1-甲基-1-乙氧基-1-烷硫基甲烷类化合物的合成研究   总被引:1,自引:0,他引:1  
本文以乙缩醛和烷基硫醇为原料,在30-35℃于四氯化碳中反应20min左右,分别合成1-甲基-1-乙氧基-1-烷硫基甲烷,经红外光谱,质谱以及核磁共振谱检测,确证了产物结构。  相似文献   

19.
Na2 1 1At and2 1 1At–Te colloid injections were prepared. By comparison with tissue distribution of Na2 1 1At and2 1 1At–Te colloid injections it has been demonstrated that the2 1 1At–Te colloid is stable in vivo. It has been shown that the radiohalogen,2 1 1At, has huge and extensive radiobiological effects in studying on the changes in histopathology, enzyme histochemistry, chromosome aberration, micronucleus frequency of bone-marrow polychromatic erythrocytes and the injury effect of2 1 1At on experimental Ehrlich ascites cells.  相似文献   

20.
Dispersed fluorescence spectra following the excitation of the CBr2A1B1-X1A1 2 and 2 bands at visible wavelengths were acquired in a discharge supersonic free jet expansion using an intensified charge-coupled device (ICCD) detector. The dispersed fluorescence spectra show signal-to-noise ratios of up to 60 and extend out to a maximum red shift frequency of 6000 cm(-1). Complete and detailed vibrational structure of the ground singlet state (X1A1) was observed. Vibrational parameters including fundamental frequencies, anharmonicities, and coupling constants were determined for the CBr2 X1A1 state. Additional vibrational structure starting at approximately 3650 cm(-1) was observed and this indicates the singlet-triplet energy gap to be >10 kcal mol(-1).  相似文献   

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