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1.
The synthesis and full characterization of the sterically demanding ditopic lithium bis(pyrazol‐1‐yl)borates Li2[p‐C6H4(B(Ph)pzR2)2] is reported (pzR = 3‐phenylpyrazol‐1‐yl ( 3 Ph), 3‐t‐butylpyrazol‐1‐yl ( 3 tBu)). Compound 3 Ph crystallizes from THF as THF‐adduct 3 Ph(THF)4 which features a straight conformation with a long Li···Li distance of 12.68(1) Å. Compound 3 tBu was found to function as efficient and selective scavenger of chloride ions. In the presence of LiCl it forms anionic complexes [ 3 tBuCl] with a central Li‐Cl‐Li core (Li···Li = 3.75(1) Å).  相似文献   

2.
双草酸硼酸锂(LiBOB)是一种新型锂盐,和商业化的LiPF_66相比具有一定优势,在锂离子电池应用上受到许多学者的关注.本文介绍了LiBOB的热稳定性、分解产物无毒和保护铝箔集流体等基本性质,对LiBOB的固相和微波两种合成方法及其在不同的有机溶剂中的溶解性、电导率、高低温性能等方面进行了论述,分析了LiBOB与正极材料搭配性能和在石墨负极上的成膜性能,并对其发展方向进行了展望.  相似文献   

3.
Guilong Li 《合成通讯》2013,43(1):34-43
An efficient acetylation of alcohols and phenols catalyzed by lithium bis(perfluoroalkylsulfonyl)-imide was developed. This acetylation features good yields, mild reaction condtions, and simple workup procedures. Furthermore, the catalyst bearing a long perfluoroalkyl chain is recoverable and readily reusable without losing any activity.  相似文献   

4.
以合成的氯代二异丙基膦为原料, 利用电化学全氟化方法, 得到全氟二异丙基膦酸锂(Li[(C3F7)2PF4]), 并对其物理和电化学性能进行了研究.  相似文献   

5.
Hexalkylditin is prepared by a Lewis acid-promoted (MgCl2) reductive reaction of bis(trialkyltin) oxide using magnesium metal as reducing agent. Hexabutyl- and hexaphenylditin are synthesized with 95% and 80% yield separately and a radical mechanism is proposed for the reaction condition. Unsymmetric ditin, Bu3Sn-SnPh3, was first synthesized by this reductive method.  相似文献   

6.
锂电池阴极材料多硫代聚苯撑的制备及电化学性能   总被引:3,自引:0,他引:3  
采用阴极材料结构改性的新方法,即以导电的聚苯撑作为骨架,将多硫链以侧链形式连接在主链上.通过苯的聚合、聚苯撑氯代,氯代聚苯撑(PPPCl)的硫代三步合成了多硫代聚苯撑(PPPS),产物结构经13CNMR谱、IR光谱、Raman光谱和元素分析进行了鉴定,其中IR谱中461和615cm-1及Raman谱中470和666cm-1峰分别表明存在S-S键和C-S键,结合其它鉴定结果,证明终产物为多硫代聚苯撑.组装成电池进行充放电性能测试表明,材料在80mA/g的电流密度下放电,比容量为987mA·h/g;在400mA/g下放电,比容量为776mA·h/g.在这两种电流密度下的利用率分别为83.5%和65.7%,具有较高的利用率和较好的大电流性能.在400mA/g的电流密度下放电时,经过25个循环的容量为307mA·h/g.  相似文献   

7.
Bis(cyclopentadienyl)samarium(II) has been shown to be insoluble in thf : ether mixtures, hence it cannot be isolated as a soluble product from the reaction of samarium with HgCp2 in thf : ether.  相似文献   

8.
LiNi0.3Co0.7O2的结构及其锂电池行为的研究   总被引:4,自引:0,他引:4  
利用XRD、XPS、CV等方法研究了LiNi0.3Co0.7O2的结构及其锂电池行为。结果表明:LiNi0.3Co0.7O2具有六方晶系空间群结构,其晶胞参数a=0.2826nm,c=1.4130nm;其表面存在Li2O;Li+在其中的化学扩散系数为1~7×10-8cm2·s-1;其锂电池在4.30~3.00V间放电容量可达120~140mA·h·g-1,放电机理为Li+在其中进行两步嵌入反应。  相似文献   

9.
制备了一种新型含氟磺酰亚胺锂盐(三氟甲基磺酰)(三氟乙氧基磺酰)亚胺锂{Li[(CF3SO2)·(CF3CH2OSO2)N], Li[TFO-TFSI]}及其与碳酸乙烯酯(EC)/碳酸甲乙酯(EMC)混合溶剂(3∶7, 体积比)组成的非水电解液. 采用核磁共振波谱(NMR)、 红外光谱(IR)、 质谱(MS)、 元素分析(EA)和离子色谱(IC)等手段对合成锂盐Li[TFO-TFSI]进行了结构表征及纯度分析. 通过差示量热扫描(DSC)和热重分析(TG)对Li[TFO-TFSI]及其电解液1.0 mol/L Li[TFO-TFSI]-EC/EMC(3∶ 7)的热学性质进行了表征. 采用交流阻抗(EIS)、 循环伏安(CV)、 计时安培法及扫描电子显微镜(SEM)等对Li[TFO-TFSI]/碳酸酯电解液的基础物化和电化学性质进行了表征. 结果表明, Li[TFO-TFSI]/碳酸酯电解液具有较好的电化学稳定性; 在4.2 V(vs. Li/Li+)以下Al箔不发生腐蚀; 室温下基于Li[TFO-TFSI]/碳酸酯电解液的Li/人造石墨和人造石墨/LiCoO2电池均保持较好的循环性能, 特别是人造石墨/LiCoO2锂离子电池循环100周后, 其比容量保持率明显高于相应的基于LiPF6/碳酸酯电解液体系的电池.  相似文献   

10.
Substituted cyclohexene-fused 3-sulfolenes have been prepared by the direct deprotonation/alkylation reactions of a readily available starting material. These fused 3-sulfolenes undergo inter- and intramolecular Diels-Alder reactions at high temperatures to give properly substituted bi- and tricyclic molecules.  相似文献   

11.
The title compound, viz. (C6F5)2NLi was prepared as dimeric complexes with Et2O or THF by the reaction of (C6F5)2NH (DFDPA) with n‐BuLi. Identity and structures were established by elemental analyses, 1H, 13C, and 19F NMR spectroscopy, and IR spectroscopy. The crystal structures of dimeric [(C6F5)2NLi(Et2O)]2 ( 1 ) and [(C6F5)2NLi(THF)]2 ( 2 ) were determined by X‐ray diffraction methods.  相似文献   

12.
The structure of LiSrY2(BO3)3 has been solved by single-crystal X-ray diffraction analysis at 298 and 113 K on different diffractometers.It crystallizes in trigonal with space group P-3m1(No.164).The cell parameters at room temperature are as follows:a = 10.3345(9),c = 6.4049(11) ,V = 592.41(13) 3,Z = 3,Mr = 448.81,F(000) = 618,μ = 21.327 mm-1 and Dc = 3.774 g/cm3.The crystal structure consists of gear-like [BY6O33] groups which are linked together by corner-sharing to form a two-dimensional layer parallel to the ab plane.These layers are connected one after another by sharing oxygen atoms with B(2) atoms along the c direction to construct a three-dimensional framework.Li and Sr atoms just occupy the cavities formed by oxygen atoms.In addition,the vibrational spectroscopy of LiSrY2(BO3)3 and photoluminescence properties of the Eu3+ doped LiSrY2(BO3)3 were also studied.  相似文献   

13.
双(三氯甲基)碳酸酯的制备和应用   总被引:23,自引:0,他引:23  
介绍了近10年双(三氯甲基)碳酸酯(简称BTC)的制备方法及其在有机合成中的应用。BTC作为剧毒的光气和双光气在合成中的低毒替代物,在制备一些重要类型有机化合物时,其反应条件温和,选择性好,收率高。  相似文献   

14.
锂离子传导材料Li1.3Ti1.7Al0.3(PO4)3是具有NASICON结构的功能材料, 与Na+进行离子交换具有选择性高的特性. 研究了在不同温度条件下NaCl和LiCl水溶液中Li1.3Ti1.7Al0.3(PO4)3上的Na/Li离子交换行为. 实验结果表明, 升高温度能显著提高Li1.3Ti1.7Al0.3(PO4)3的Na/Li交换反应速率, 提高LiCl中杂质Na的分离效果.  相似文献   

15.
IntroductionRecently ,theBaylis Hillmanreactionhasbecomeaveryhotfieldforsyntheticchemists ,1 12 witharecentexampleofacatalyticasymmetricversion .13 IthasbeendisclosedthatthecombinationofaLewisbasesuchaschalcogenides ,amines ,phosphinesorquaternaryammo niumhali…  相似文献   

16.
In order to understand the chelation process and investigate the intermediate species as a step towards verifying the exact functional groups that are involved in bonding with transition metals, specifically Cu(II) and Zn(II), pH-oscillotitrimetric (pHOT) and volumetric-oscillographic (VOG) methods have been profoundly used. Alizarin Red S (ARS) - as one of the chameleon compounds (chromogenic) - confirms its different approach of bonding with copper and zinc in different mediums. These two methods thoroughly confirm the adequate conditions for each metal to chelate with ARS. pH is responsible for the ambience in which the formation energy in its less value for the salt or complex to be formed, confirming that pH  =  5 is the value that allows Cu(II) to bond with ARS, whereas Zn(II) bonds at pH = 6. A new approach has been also suggested as to how to discuss the titrimetric curves in both methods, taking into account the importance of ‘volumetric-oscillographs’ that give more information when analysed appropriately. Volumetric-oscillographs have been shown and utilized as fingerprint spectrums to track any change in the solutions and firmly expect the compounds that can be step-by-step formed during titration operation. The resulting-in rules have been suggested during reading the graphs. Moreover, the competition between these two metals to chelate with ARS has been extensively studied.  相似文献   

17.
1,2-二(三甲硅基环戊二烯基)四甲基二硅烷与Fe(CO)5在二甲苯中于105~110℃反应除分离到少量标题化合物(Me2SiSiMe2)[η-(3-Me3SiC5H3Fe(CO)]2(μ-CO)2(5)外,主要是生成了脱Me3Si基的产物(Me2SiSiMe2)[η-C5H4Fe(CO)]2(μ-CO)2(1)及1的热重排异构体[Me2SiC5H4-Fe(CO)2]2(2).将5的二甲苯溶液加热回流18h,则转化为其异构体[Me2Si(Me3SiC5H3)Fe(CO)2]2(6).脱硅基发生在由相应反应物制备5的过程中。且脱硅基是与反应物中(Me2SiSiMe2)桥的存在有关。5的晶体结构经X射线衍射测定属单斜晶系,P21/m空间群,晶体学数据:a=0.6780(1)nm,b=2.2303(9)nm,c=0.9988(1)nn,;β=98.96(1)°,V=1.4960nm3.Z=2,Dc=1.36g/cm3.  相似文献   

18.
在乙醇水溶液中,以Na BF4为催化剂,通过吲哚与芳香醛间的串联反应合成了二吲哚甲烷衍生物。考察了催化剂种类、反应介质、温度、反应时间等因素对反应的影响,在优化条件下以较高产率得到了一系列目标产物。  相似文献   

19.
以双酚化合物及对卤苯酚为起始原料,经用苄基保护、乌尔曼成醚、选择性硝化和还原脱保护4步反应,合成了具有双酚芳香醚结构的4个新型聚苯并噁唑单体:双(3-氨基-4-羟基苯基)双酚醚类化合物的盐酸盐。 确定了乌尔曼成醚反应的最佳工艺条件,证明硝化反应只发生在对卤苯酚苄保护基的邻位,改进了还原脱保护反应的成盐及后处理条件,提高了产物的质量和收率,4步反应总收率可达54.0%。 采用红外光谱、核磁共振H谱和高分辨质谱表征了每步产物的化学结构。  相似文献   

20.
Alkan M  Kharun M  Chmilenko F 《Talanta》2003,59(3):605-611
The present work describes a selective and rapid method for the determination of molybdenum with Alizarin Red S (ARS) in the presence of a water soluble polymer, poly(sulfonylpiperidinylmethylene hydroxide) (PSPMH). The ARS modified by PSPMH reacts with molybdenum(VI) in the solutions of pH 3.4-4.0 to produce a red complex. The composition of the complex is 1:4:1 mol ratio of Mo(VI): ARS:PSPMH. The complex obeys Beer's law from 0.05 to 5.50 μg ml−1 with an optimum range. The molar absorptivity is 2.1×104 l mol−1 cm−1 at 500 nm. The interference effects of the foreign cations have been examined and it has been determined that only Cu(II), Al(III) and Fe(III) have to be masked by EDTA and tungsten can be tolerated till 4-fold of molybdenum in case of masking by citrate. The method has been applied to the determination of geological samples without solvent extraction or separation steps.  相似文献   

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