N－芳基－2－乙基－3－羟基－4－吡啶酮的微波合成

用微波辐射从2－乙基－3－羟基－4－吡喃酮和芳胺合成了系列N－芳基－2－ 乙基－3－羟基－4－吡啶酮，并对产物进行了紫外、红外、氢核磁和质谱表征。     

SYNTHESIS OF 4－S－（1＂－ARYL－TETRAZOLE－5＂－YL）－4－DEOXY－4＇－DEMETHYL－EPIPODOPHYLLOTOXIN ANALOGUES

ＳＹＮＴＨＥＳＩＳ ＯＦ ４－Ｓ－（１＂－ＡＲＹＬ－ＴＥＴＲＡＺＯＬＥ－５＂－ＹＬ）－４－ＤＥＯＸＹ－４＇－ＤＥＭＥＴＨＹＬ－ＥＰＩＰＯＤＯＰＨＹＬＬＯＴＯＸＩＮ ＡＮＡＬＯＧＵＥＳ￥ＫｕａｎＫｅＬＵ；ＦａｎｇＭｉｎＬＩＵａｎｄＹａｏＺｕＣＨＥＮ（Ｄ...     

2－乙基－1－（α－呋喃基）－1－戊烯－4－炔－3醇的合成

２－乙基－１－（α－呋喃基）－１－戊烯－４－炔－３醇的合成肖蓉，孙悦（成都科技大学化学系６１００６５）涂君俐（中国科学院成都有机化学研究所，６１００４１）蚊香和电热片是拟除虫菊醋类药剂，也是家庭卫生用药的代表性剂型。如果能开发出挥发性高，在非加热条件...     

A Highly Stereoselective Synthesis of 2－Carbomethoxy－3－aryl－4－carboethoxy－5－methyl－cis－2，3－dihydrofurans

ＡＨｉｇｈｌｙＳｔｅｒｅｏｓｅｌｅｃｔｉｖｅＳｙｎｔｈｅｓｉｓｏｆ２－Ｃａｒｂｏｍｅｔｈｏｘｙ－３－ａｒｙｌ－４－ｃａｒｂｏｅｔｈｏｘｙ－５－ｍｅｔｈｙｌ－ｃｉｓ－２，３－ｄｉｈｙｄｒｏｆｕｒａｎｓＤＩＮＧＷｅｉ－ｙｕ；ＣＨＥＮＹａ－ｌｉ；ＺＨＡＮＧ...     

1－芳酰基－3－烷基－6－羟基－6－芳基富烯的合成

１－芳酰基－３－烷基－６－羟基－６－芳基富烯的合成焦纶基,董育斌,马玉道（山东大学应用化学研究所,济南,２５０１００）关键词富烯,二茂铁,芳酰化,合成前文［１］曾报道过甲基锂、苯基锂与６,６－二烷基富烯加成物的芳酰化。为进一步探讨取代环戊二烯负离子的...     

SYNTHESIS OF 5－SUBSTITUTED－2－CHLORO－6－METHYL－4， 7－DIOXOBENZOTHIAZOLE DERIVATIVES

ＳＹＮＴＨＥＳＩＳ ＯＦ ５－ＳＵＢＳＴＩＴＵＴＥＤ－２－ＣＨＬＯＲＯ－６－ＭＥＴＨＹＬ－４， ７－ＤＩＯＸＯＢＥＮＺＯＴＨＩＡＺＯＬＥ ＤＥＲＩＶＡＴＩＶＥＳ￥ＣｕｉＨｕａＬＩＵ；ＢｉｎＬＵ；ＪｉｎｇＬｉｎｇＺＨＡＮＧ（Ｉｎｓｔｉｔｕｔｅｏｆｏｒｇ...     

锆－7－碘－8－羟基喹啉－5－磺酸－EDTA－表面活性剂体系的荧光光度法研究

在ｐＨ６．２的ＨＡｃ－ＮａＡｃ缓冲溶液中，有溴化十六烷基三甲基铵（ＣＴＭＡ８）存在下，Ｚｒ（Ⅳ）与７－碘－８－羟基喹啉－５－磺酸（Ｈ＿２ＱＳＩ）及ＥＤＴＡ形成了四元荧光配合物。其组成为：Ｚｒ：Ｈ＿ＱＳＩ：ＥＤＴＡ：ＣＴＭＡＢ＝１：１：１：３。据此建立了错的选择性好、灵敏度高的荧光测定方法。方法检测限为１．２ｎｇ／ｍＬ。锆的线性范围为１．６ｎｇ～１．０μｇ／ｍＬ。用于铜合金中微量锆的测定，结果令人满意。     

Crystal and Molecular Structure of 3，4－diphenyl－5－ethyl－5－methyl－1，3，4－diazaphospholidin－2－thione－4－oxide

ＣｒｙｓｔａｌａｎｄＭｏｌｅｃｕｌａｒＳｔｒｕｃｔｕｒｅｏｆ３，４－ｄｉｐｈｅｎｙｌ－５－ｅｔｈｙｌ－５－ｍｅｔｈｙｌ－１，３，４－ｄｉａｚａｐｈｏｓｐｈｏｌｉｄｉｎ－２－ｔｈｉｏｎｅ－４－ｏｘｉｄｅ￥ＦｅｎｇＫｅ－Ｓｈｅｎｇ；ＣｈｅｎＲｕ－Ｙｕ（Ｉ...     

4－叔丁基－β－氯－α－甲基肉桂醛的合成

从苯和叔了醇出发，经过３步反应合成得标题化合物，总收率在６８％以上。     

The Synthesis of 1－O－β－D－（5－Aryl－2－furoyl）AcetylatedSugarsbyPhaseTransferCatalysis

以相转移催化法使α－溴代乙酰基葡萄糖，α－溴代乙酰基木糖和α－溴代乙酰基葡萄糖醛酸甲酯与５－芳基－２－呋喃甲酸在水－有机相体系中反应，合成了１４个未见文献报道的糖酯类化合物，其结构经ＩＲ、１ＨＮＭＲ、ＭＳ等证实，生物活性实验正在进行之中     

Biomimetic Synthesis of Metal Ion‐Doped Hierarchical Crystals Using a Gel Matrix: Formation of Cobalt‐Doped LiMn2O4 with Improved Electrochemical Properties through a Cobalt‐Doped MnCO3 Precursor

We have synthesized spinel type cobalt‐doped LiMn₂O₄ (LiMn_2?yCo_yO₄, 0≤y≤0.367), a cathode material for a lithium‐ion battery, with hierarchical sponge structures via the cobalt‐doped MnCO₃ (Mn_1‐xCo_xCO₃, 0≤x≤0.204) formed in an agar gel matrix. Biomimetic crystal growth in the gel matrix facilitates the generation of both an homogeneous solid solution and the hierarchical structures under ambient condition. The controlled composition and the hierarchical structure of the cobalt‐doped MnCO₃ precursor played an important role in the formation of the cobalt‐doped LiMn₂O₄. The charge–discharge reversible stability of the resultant LiMn_1.947Co_0.053O₄ was improved to ca. 12 % loss of the discharge capacity after 100 cycles, while pure LiMn₂O₄ showed 24 % loss of the discharge capacity after 100 cycles. The parallel control of the hierarchical structure and the composition in the precursor material through a biomimetic approach, promises the development of functional materials under mild conditions.     

锂离子电池正极材料LiV3O8-xClx的低温固相法合成及电化学性能研究

采用低温固相法成功地合成了锂离子电池正极材料LiV3O8-xClx (x=0.00,0.05,0.10,0.15)。分别用XRD、SEM、充放电实验、循环伏安、交流阻抗等测试方法研究了Cl- 的掺入对LiV3O8结构、形貌及电化学性能的影响。结果表明, Cl-的掺入显著地提高了材料的充放电循环性能。当掺杂量 x=0.10时,材料的循环性能最好, 循环100周后放电容量仍为198.6 mAh/g。     

Electrochemical Preparation of N‐Doped Cobalt Oxide Nanoparticles with High Electrocatalytic Activity for the Oxygen‐Reduction Reaction

Nitrogen‐doped CoO (N‐CoO) nanoparticles with high electrocatalytic activity for the oxygen‐reduction reaction (ORR) were fabricated by electrochemical reduction of CoCl₂ in acetonitrile solution at cathodic potentials. The initially generated, highly reactive nitrogen‐doped Co nanoparticles were readily oxidized to N‐CoO nanoparticles in air. In contrast to their N‐free counterparts (CoO or Co₃O₄), N‐CoO nanoparticles with a N content of about 4.6 % exhibit remarkable ORR electrocatalytic activity, stability, and immunity to methanol crossover in an alkaline medium. The Co?N_x active sites in the CoO nanoparticles are held responsible for the high ORR activity. This work opens a new path for the preparation of nitrogen‐doped transition metal oxide nanomaterials, which are promising electrocatalysts for fuel cells.     

Microwave‐assisted Synthesis and Its Reversible Li‐storage Properties of Porous Sheet‐like Co3O4

Porous Co₃O₄ nanosheets were designed and fabricated from common Co(NO₃ )₂ solution without any surfactants or templates under microwave radiation conditions. After the microstructures and morphologies were characterized by scanning electron microscope (SEM ), X‐ray powder diffraction (XRD ), transmission electron microscopy (TEM ), and N₂ absorption/desorption isotherms techniques, the obtained Co₃O₄ nanosheets were applied for reversible Li‐storage, displaying larger capacity, better cycling performance and rate capability, i.e., a reversible specific capacity of ca. 800 mAh /g during initial 30 cycles and a reversible capacity of 450 mAh /g at 2C for Co₃O₄ nanosheets, which were almost twice higher than those for Co₃O₄ nanoparticles. The improved cycling stability could be attributed to the remarkable synergistic effects between porous structures and nanosheet‐like morphologies.     

Electrochemical Phase Evolution of Metal‐Based Pre‐Catalysts for High‐Rate Polysulfide Conversion

In situ evolution of electrocatalysts is of paramount importance in defining catalytic reactions. Catalysts for aprotic electrochemistry such as lithium–sulfur (Li‐S) batteries are the cornerstone to enhance intrinsically sluggish reaction kinetics but the true active phases are often controversial. Herein, we reveal the electrochemical phase evolution of metal‐based pre‐catalysts (Co₄N) in working Li‐S batteries that renders highly active electrocatalysts (CoS_x). Electrochemical cycling induces the transformation from single‐crystalline Co₄N to polycrystalline CoS_x that are rich in active sites. This transformation propels all‐phase polysulfide‐involving reactions. Consequently, Co₄N enables stable operation of high‐rate (10 C, 16.7 mA cm^?2) and electrolyte‐starved (4.7 μL mg_S^?1) Li‐S batteries. The general concept of electrochemically induced sulfurization is verified by thermodynamic energetics for most of low‐valence metal compounds.     

The Role of Reduced Graphite Oxide in Transition Metal Oxide Nanocomposites Used as Li Anode Material: An Operando Study on CoFe2O4/rGO

A composite consisting of CoFe₂O₄ spinel nanoparticles and reduced graphite oxide (rGO) is studied as an anode material during Li uptake and release by applying synchrotron operando X‐ray diffraction (XRD) and operando X‐ray absorption spectroscopy (XAS), yielding a comprehensive picture of the reaction mechanisms. In the early stages of Li uptake, a monoxide is formed as an intermediate phase containing Fe²⁺ and Co²⁺ ions; this observation is in contrast to reaction pathways proposed in the literature. In the fully discharged state, metallic Co and Fe nanoparticles are embedded in an amorphous Li₂O matrix. During charge, metallic Co and Fe are oxidized simultaneously to Co²⁺ and Fe³⁺, respectively, thus enabling a high and stable capacity to be achieved. Here, evidence is presented that the rGO acts as a support for the nanoparticles and prevents the particles from contact loss. The operando investigations are complemented by TEM, Raman spectroscopy, galvanostatic cycling, and cyclic voltammetry.     

Application of Nanosized Cu0.5Co0.5Fe2O4 Spinel Ferrite as a Nanocatalyst in the Synthesis of 14‐Aryl‐14H‐dibenzo[a,j]xanthene Derivatives under Solvent‐free Conditions

Copper and cobalt substituted spinel ferrites Cu_1‐xCo_xFe₂O₄ (0≤X≤1) have been synthesized by using hydrothermal method. The resultant spinel ferrites were systematically characterized by different techniques such as X‐ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X‐ray spectroscopy (EDX), and Fourier transform infrared spectroscopy (FT‐IR). It was indicated that all the resultant spinel ferrites obtained by the hydrothermal method had the single‐phase crystalline. The resultant spinel ferrites were employed in the synthesis of 14‐aryl‐14‐H‐dibenzo[a,j]xanthene derivatives. It was found that the nanocatalyst Cu_0.5Co_0.5Fe₂O₄ displays the best performance in the synthesis of 14‐aryl‐14H‐dibenzo[a,j]xanthenes. The catalyst was reused several times without significant loss of its activity for the preparation of desired product. In addition high yields of the products, solvent‐free conditions and reusability of the catalyst are other worthwhile advantages of the present study.     

Active Electron Density Modulation of Co3O4‐Based Catalysts Enhances their Oxygen Evolution Performance

Despite the fact that many strategies have been developed to improve the efficiency of the oxygen evolution reaction (OER), the precise modulation of the surface electronic properties of catalysts to improve their catalytic activity is still challenging. Herein, we demonstrate that the surface active electron density of Co₃O₄ can be effectively regulated by an argon‐ion irradiation method. X‐ray photoelectron and synchrotron x‐ray absorption spectroscopy, UV photoelectron spectrometry, and DFT calculations show that the surface active electron density band center of Co₃O₄ has been upshifted, leading to a significantly enhanced absorption capability of the oxo group. The optimized Co₃O₄‐based catalysts exhibit an excellent overpotential of 260 mV at 10 mA cm^?2 and Tafel slope of 54 mV dec^?1, superior to the capability of the benchmark RuO₂, representing one of the best Co‐based OER catalysts. This approach could guide the future rational design and discovery of ideal electrocatalysts.     

Hollow and Yolk‐Shell Iron Oxide Nanostructures on Few‐Layer Graphene in Li‐Ion Batteries

We report a simple and template‐free strategy for the synthesis of hollow and yolk‐shell iron oxide (FeO_x) nanostructures sandwiched between few‐layer graphene (FLG) sheets. The morphology and microstructure of this material are characterized in detail by X‐ray diffraction, X‐ray absorption near‐edge structure, X‐ray photoelectron spectroscopy, Raman spectroscopy, scanning and transmission electron microscopy. Its properties are evaluated as negative electrode material for Li‐ion batteries and compared with those of solid FeO_x/FLG and two commercial iron oxides. In all cases, the content of carbon in the electrode has a great influence on the performance. The use of pristine FLG improves the capacity retention and further enhancement is achieved with the hollow structure. For a low carbon loading of 18 wt. %, the presence of metallic iron in the hollow and yolk‐shell FeO_x/FLG composite significantly enhances the capacity retention, albeit with a relatively lower initial reversible capacity, retaining above 97 % after 120 cycles at 1000 mA g^?1 in the voltage range of 0.1–3.0 V.     

The Proportion of Fe‐NX,N Doping Species and Fe3C to Oxygen Catalytic Activity in Core‐Shell Fe‐N/C Electrocatalyst

A bifunctional oxygen electrocatalyst composed of iron carbide (Fe₃C) nanoparticles encapsulated by nitrogen doped carbon sheets is reported. X‐ray photoelectron spectroscopy and X‐ray absorption near edge structure revealed the presence of several kinds of active sites (Fe?N_x sites, N doping sites) and the modulated electron structure of nitrogen doped carbon sheets. Fe₃C@N‐CSs shows excellent oxygen evolution and oxygen reduction catalytic activity owing to the modulated electron structure by encapsulated Fe₃C core via biphasic interfaces electron interaction, which can lower the free energy of intermediate, strengthen the bonding strength and enhance conductivity. Meanwhile, the contribution of the Fe?N_x sites, N doping sites and the effect of Fe₃C core for the electrocatalytic oxygen reaction is originally revealed. The Fe₃C@N‐CSs air electrode‐based zinc‐air battery demonstrates a high open circuit potential of 1.47 V, superior charge‐discharge performance and long lifetime, which outperforms the noble metal‐based zinc‐air battery.