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1.
1, 1-Dicyano-2, 2-bis(trifluoromethyl)ethylene and 3, 3-dicyano-2-(trifluoromethyl)acrylates react with primary arylamines in the presence of ketones to form 1, 1-aryl-1, 4-dihydropyridme derivatives under mild conditions. The mechanism of this three-component reaction includes the formation of Schiffs bases as intermediates. 1, 4-Dihydropyridine derivatives, which are the products of three-component heterocyclization, were also obtained by reaction the corresponding Schiffs bases with 1, 1-dicyano-2-(trifluoromethyl)ethylenes.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 552–559, March, 1993.For preliminary communication see Ref. 1.  相似文献   

2.
以易得的1-金刚烷甲酸为原料, 合成了一系列对称桥头二取代金刚烷衍生物. 由1-金刚烷甲酸经Koch-Haaf羰基化反应得到1,3-金刚烷二甲酸(1); 化合物1经还原得到1,3-金刚烷二甲醇(2); 化合物2在HBr-ZnBr2体系中经溴代反应得1,3-二(溴甲基)金刚烷(3); 同时经Apple-Lee反应将化合物2转化得到1,3-二(氯甲基)金刚烷(4). 采用红外光谱和核磁共振氢谱等手段表征了产物的结构, 提出了可能的反应机理, 并对合成条件进行了优化.  相似文献   

3.
A benchmark comparison for different computational methods and basis sets has been presented. In this study, five computational methods (Hartree–Fock (HF), MP2, B3LYP, MPW1MP91, and PBE1PBE) along with 18 basis sets have been applied to optimize the geometry of carbon disulfide (CS2), and further calculate the vibrational frequencies of the optimized geometries. The differences between the calculated frequencies and corresponding experimental data are used to evaluate the efficiency of each combination of computational method and basis set. The comparison of frequency difference indicates that B3LYP generally gives the best prediction of frequencies for CS2, whereas the other two density functional theory (DFT) methods, i.e., MPW1PW91 and PBE1PBE, often give parallel results. Although MP2 predicts the frequencies with accuracy almost as good as those from DFT methods, in a particular case, HF calculation outperforms MP2 as well as MPW1PW91 and PBE1PBE for prediction of the frequency of asymmetrical stretching for CS2. © 2013 Wiley Periodicals, Inc.  相似文献   

4.
报道了5-芳香二酮-1H-四氮唑(2)的一锅合成法,并且首次报道了1-甲基-1-甲氧基乙基作为四氮唑氮原子的保护基团,保护与脱保护反应条件温和,操作简便,收率高,为该类化合物的合成提供了一条捷径.采用该方法共合成6个未见文献报道的5-芳香二酮-1H-四氮唑类新化合物,以用于药理活性筛选.  相似文献   

5.
利用琥珀酸为鳌合剂的湿化学法成功合成了一系列锂离子电池正极材料LiNi1/3Mn1/3Co1/3O2,在合成过程中改变琥珀酸与金属离子摩尔比(R)并研究了这一参数对合成LiNi1/3Mn1/3Co1/3O2材料物理及电化学性质的影响.采用热重、X射线衍射、Rietveld精修、扫描电镜以及超导量子干涉仪对反应机理、材料的结构、形貌以及磁学性质进行了详细表征.得到最佳合成条件为R=1,此时LiNi1/3Mn1/3Co1/3O2的阳离子混排度最低.此外,通过Rietveld精修得到该材料阳离子混排度的结果与通过磁学方法得到的结果定量相符,如对于在R=1条件下合成的样品,Rietveld精修结果显示其阳离子混排度为1.85%,而超导量子干涉仪的测试结果为1.80%.当充放电区间为3.0-4.3V,电流密度为0.2C(1C=160mA·g-1)时,该样品的首次放电容量为161mAh·g-1,库仑效率为93.1%,经过50次循环后,容量保持率可达91.3%.  相似文献   

6.
张晶蕾  王洋 《有机化学》2008,28(4):723-726
文献曾报道以铝-镍合金为还原剂, 在稀碱水溶液中, 可以将1-萘酚(1)以高收率还原为5,6,7,8-四氢-1-萘酚(2). 本研究工作发现, 在相同的条件下该反应除了生成少量2外, 3,4-二氢-2H-萘-1-酮(3)和1,2,3,4-四氢-1-萘酚(4)为主要产物, 该结果明显不同于文献报道, 对反应产物分布及其可能机理进行了探讨. 该还原反应体系为3,4-二氢-1(2H)-萘酮(3)和1,2,3,4-四氢-1-萘酚(4)的合成提供了一条新途径.  相似文献   

7.
研究了用双氧水为氧化剂,钛硅分子筛TS-1催化1-丁烯环氧化反应的溶剂效应.研究发现,在质子性溶剂中1-丁烯环氧化反应活性高于非质子性溶剂,而以甲醇为溶剂H2O2转化率最高.分别利用碱性添加物稀氨水溶液和酸性添加物稀盐酸溶液调变反应介质的pH值,考察了介质的pH值对1-丁烯环氧化反应的影响,结果表明,随pH值提高,1,2-环氧丁烷(B0)的选择性略提高,但是过量稀氨水的加入会导致催化剂失活,双氧水的转化率及利用率明显下降.与钛硅分子筛催化丙烯环氧化相比,酸性添加物的加入对反应结果的影响不大,随反应介质的pH值降低1,2-环氧丁烷的选择性没有明显下降.  相似文献   

8.
闫芳  叶乃清  田华  钟卓洪 《化学通报》2011,74(5):429-433
以硝酸锂、四水合乙酸镍、四水合乙酸钴、四水合乙酸锰、氨水和草酸为原料,通过共沉淀-燃烧法合成了锂离子电池正极材料LiNi1/3Co1/3Mn1/3O2,采用XRD、SEM和充放电试验对合成产物进行了表征,研究了回火处理对合成产物结构和电化学性能的影响.实验结果表明,嫩烧反应形成的LiNi1/3C1/3Mn31/3O2结...  相似文献   

9.
共沸蒸馏法制备高性能LiNi_(1/3)Co_(1/3)Mn_(1/3)O_2正极材料   总被引:1,自引:0,他引:1  
三元复合氧化物镍钴锰酸锂(LiNi1/3Co1/3Mn1/3O2)因兼有LiNiO2和LiCoO2的优点,被认为是最有可能取代LiCoO2的新型正极材料而受到广泛关注.本文采用一种改进的共沉淀方法合成了LiNi1/3Co1/3Mn1/3O2,以共沸蒸馏干燥前驱物.结果表明,共沸干燥法最终得到的产物比普通干燥法得到的产物具有更高的比容量、更好的循环性能以及更优的倍率性能.究其原因,可归结为共沸干燥得到的样品颗粒更小,且粒径分布更均匀,球形度高,比表面积大,促进了锂离子的扩散,因而提高了其电化学性能.  相似文献   

10.
The influence of process parameters on the epoxidation of 2-buten-1-ol with 30 % hydrogen peroxide using the titanium silicalite TS-1 is presented. The studies were carried out under autogenic pressure (in autoclave). Methanol was used as a solvent in this process. The influence of temperature, 2-buten-1-ol to hydrogen peroxide mole ratio, amount of solvent used, TS-1 catalyst content, and reaction time on the reaction was studied. The major product of this reaction, 2,3-epoxybutan-1-ol (EB), has numerous applications in chemical industry.  相似文献   

11.
TiO2包覆对LiCO1/3Ni1/3Mn1/3O2材料的表面改性   总被引:1,自引:0,他引:1  
为了提高材料LiCo1/3Ni1/3MnO2的循环件能,采用浸渍-水解法对其进行TiO2包覆.用X射线衍射(XRD)、电化学交流阻抗谱(EIS)、电感耦合等离子体发射光谱(ICP-OES)和恒流允放电测试研究包覆材料的结构和电化学性能.TiO2仅在材料表面形成包覆层,并未改变材料的结构.TiO2包覆能提高材料LiCo1/3Ni1/3Mn1/3O2的倍率性能和循环性能,TiO2包覆后的材料在5.0C(1.0C=160 mA·g-1)下的放电容量达到0.2C下的66.0%,而包覆前的材料在5.0C下的放电容量仅为其0.2C下的31.5%.包覆后的材料在2.0C下循环12周后的容最没有衰减,而未包覆的材料容量保持率仅为94.4%.EIS测试表明包覆材料性能的提高是由于循环过程中材料的界面稳定性得到了提高.循环后材料的XRD和ICP-OES测试表明,包覆层能提高材料LiCo1/3Ni1/3Mn1/3O2的结构稳定性.  相似文献   

12.
2a,4-Disubstituted 2,2a,3,4-tetrahydro-2-phenyl-1H-azeto[2,1-d][ 1,5]benzothiazepin-1-ones, as well as 2-substi-tuted 2,3-dihydro-3-phenylacetyl-2-styryl-benzothiazoles and 4a,6-disubstituted 3- .benzyl-4a,5-d/hydro-2-phenyl-1H,6H-[1,3]oxazino[2,3-d][1,5]benzothiazepin-1-ones, were obtained from the reaction of 2,4-disubstituted 2,3-dihydro-1,5-benzothiazepines with phenylacetyl chloride in the presence of triethylamine. The mechanism for the formation of 4a,5-dihydro-1H,6H-[1,3]oxazino[2,3-d][1,5]benzothiazepin-1-ones, 2,3-dihydro-1,3-oxazin-4-one derivatives, was suggested.  相似文献   

13.
Interleukin-1 beta (IL-1β) has diverse physiological functions and plays important roles in health and disease. In this report, we focus on its function in the production of pro-inflammatory cytokines, including IL-6 and IL-8, which are implicated in several autoimmune diseases and host defense against infection. IL-1β activity is markedly dependent on the binding affinity toward IL-1 receptors (IL-1Rs). Several studies have been conducted to identify suitable small molecules that can modulate the interactions between 1L-1β and 1L-1R1. Based on our previous report, where DPIE [2-(1,2-Diphenyl-1H-indol-3-yl)ethanamine] exhibited such modulatory activity, three types of DPIE derivatives were synthesized by introducing various substituents at the 1, 2, and 3 positions of the indole group in DPIE. To predict a possible binding pose in complex with IL-1R1, a docking simulation was performed. The effect of the chemicals was determined in human gingival fibroblasts (GFs) following IL-1β induction. The DPIE derivatives affected different aspects of cytokine production. Further, a group of the derivatives enabled synergistic pro-inflammatory cytokine production, while another group caused diminished cytokine production compared to DPIE stimulation. Some groups displayed no significant difference after stimulation. These findings indicate that the modification of the indole site could modulate IL-1β:IL1R1 binding affinity to reduce or enhance pro-inflammatory cytokine production.  相似文献   

14.
线型1,2-邻二萘醌-1-肟(1-nqo)钌配合物的合成   总被引:1,自引:0,他引:1  
报道了含C_(16)长碳链线型1,2-邻二萘醌-1-肟(1-nqo)钌配合物trans-,cis- 及cis-,cis-[Ru(1-nqo)_2(CO)(spy)] (3)及(4)含C_(18)长碳链线型1-nqo钌配合 物cis-,cis-[Ru(1-nqo)_2(CO)(opy)] (5),trans-,trans-[Ru(1-nqo)_2(opy) _2] (6)的合成。利用红外、FAB质谱、核磁共振氢谱及紫外-可见吸收光谱表征配 合物的结构,利用~1H-~1H偶合二维核磁技术对核磁共振峰进行指认。  相似文献   

15.
该文基于酶辅助靶标循环信号放大策略构建了用于黄曲霉毒素B1(AFB1)高灵敏检测的化学发光适体传感器。以G-四链体/氯化血红素DNA酶为信号分子设计了免标记的适体探针H1-S1和发夹探针H2。适体探针结合目标AFB1,在核酸外切酶I辅助下,触发靶标循环反应产生发夹H1。发夹H1与H2杂交,释放出完整的G-四链体序列,并进一步与氯化血红素结合形成G-四链体/氯化血红素DNA酶。DNA酶通过催化氧化鲁米诺-H2O2化学发光体系产生化学发光信号,实现AFB1的放大检测。在最优实验条件下,化学发光强度与AFB1质量浓度的对数在0.001~100 ng/mL范围内呈良好的线性关系,相关系数(r2)为0.9955,检出限为0.93 pg/mL,回收率为93.7%~107%。该适体传感器操作简单、灵敏度高、特异性好,在黄曲霉毒素污染检测方面具有良好的应用前景。  相似文献   

16.
用改进硬脂酸溶胶-凝胶法制备了量子顺电体La1/2Na1/2TiO3纳米晶,用差热-热重分析和X射线衍射测试了样品的晶化过程及物相结构,用FTIR和Raman光谱表征了其谱学特性.  相似文献   

17.
2-Pyrrolidones have aroused enormous interest as a useful structural moiety in drug discovery; however, not only does their syntheses suffer from low selectivity and yield, but also it requires high catalyst loadings. The radical cyclization of 1,n-enynes and 1,n-dienes has demonstrated to be an attractive method for the synthesis of 2-pyrrolidones due to its mild reaction conditions, fewer steps, higher atom economy, excellent functional group compatibility, and high regioselectivity. Furthermore, radical receptors with unsaturated bonds (i. e. 1,n-enynes and 1,n-dienes) play a crucial role in realizing radical cyclization because of the ability to selectively introduce one or more radical sources. In this review, we discuss representative examples of methods involving the radical cyclization of 1,n-enynes and 1,n-dienes published in the last five years and discuss each prominent reaction design and mechanism, providing favorable tools for the synthesis of valuable 2-pyrrolidone for a variety of applications.  相似文献   

18.
含苯并三唑色酮及1,3,4-噁二唑啉类化合物的合成   总被引:9,自引:0,他引:9  
研究了一种简便的合成2位含氮杂环色酮类化合物的方法。1H-苯并三唑与ClCH_2COOH反应制得1H-苯并三唑-1-乙酸(1),以此为原料合成了一系列2位合1H-苯并三唑-1-甲基色酮(5)和相关的1,3,4-噁二唑啉衍生物(8)。  相似文献   

19.
An environmentally‐friendly and operationally‐simple process for the synthesis of 1‐iodoalk‐1‐ynes under mild conditions catalyzed by CuI/TBAB in water under air was developed in this study. Catalyst loadings of CuI as low as 1–2 mol% gave 1‐iodoalk‐1‐ynes in good to high yields, and the residual aqueous solution after extraction with hexane could be reused for the next reaction without any treatment.  相似文献   

20.
宋国强  王钒  张灏  凌达仁 《合成化学》2000,8(3):216-219
在无水乙醚中-1-锂代环已烯和烯丙基溴化镁于为水溴铧锌作用下发生金属化克兰节省理排反应,生成2-烯丙基-1,1-偕二金属环乙烷。通过对温度1溶剂量物凤料顺序等重排反应主要影响因素的考察和优化,可使2-烯丙基-1,1-偕二环已烷的收率达到65%。  相似文献   

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