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1.
以二苯亚砜为起始反应物,通过改进反应溶剂,首先合成了溴化三苯基硫盐,大大缩短了反应时间,提高了该盐的反应收率.再运用银盐置换法,合成了光致酸发生剂——对甲基苯磺酸三苯基硫盐,并对其进行了红外和核磁共振表征.  相似文献   

2.
以咪唑和吡啶作为阳离子基体,设计合成了3种具有烷基膦酸功能基团的功能型离子液体,利用傅里叶变换红外(FTIR)光谱、核磁共振氢谱(1H NMR)和元素分析对离子液体的结构进行了确认,测定了离子液体的相转变温度、热稳定性、密度和黏度等物理性能,并对硝酸介质中萃取铀酰离子进行了研究.结果表明,所制备的功能离子液体可同时作为稀释剂和萃取剂,在室温环境下实现对铀(Ⅵ)的萃取,萃取率可达到90%以上.  相似文献   

3.
离子液体催化邻二甲苯氯甲基化反应   总被引:1,自引:0,他引:1  
制备了8种不同链长的溴化烷基咪唑盐和4种丁基类甲基咪唑六氟磷酸盐、四氟硼酸盐、全氟丁基磺酸盐及氯化盐离子液体,研究了咪唑盐类离子液体催化邻二甲苯、氯化氢、多聚甲醛为起始原料的氯甲基化反应. 考察了离子液体类型、催化剂用量、反应温度及反应时间对反应的影响. 反应产物采用气相色谱法进行定量分析;采用GC-MS测试技术进行了定性分析. 结果表明,[C12mim]Br(溴化1-十二烷基-3-甲基咪唑盐)是最适合的催化剂. 其最佳反应条件是:离子液体摩尔分数为4%(与邻二甲苯的摩尔比),温度70 ℃,反应时间10 h,产物收率可达89.8%,TON数达到22.4.  相似文献   

4.
以咪唑和吡啶作为阳离子基体, 设计合成了3种具有烷基膦酸功能基团的功能型离子液体, 利用傅里叶变换红外(FTIR)光谱、 核磁共振氢谱(1H NMR)和元素分析对离子液体的结构进行了确认, 测定了离子液体的相转变温度、 热稳定性、 密度和黏度等物理性能, 并对硝酸介质中萃取铀酰离子进行了研究. 结果表明, 所制备的功能离子液体可同时作为稀释剂和萃取剂, 在室温环境下实现对铀(Ⅵ)的萃取, 萃取率可达到90%以上.  相似文献   

5.
通过三烷基铴四氟硼酸盐与烷基咪唑作用一步合成了一系列二烷基咪唑四氟硼酸离子液体,所有反应在室温下5~120分钟内完成,产率均>99%.对以上离子液体中可能含有的主要杂质进行了测定,结果表明,通过一步法合成的离子液体中卤素离子、Na+和卤代烷的含量均低于检出限,烷基咪唑的含量在0~0.53wt%范围内.此方法具有简单、快速、清洁等优点,是一种制备高纯度离子液体可行方法.  相似文献   

6.
从N,N’-二烷基酯联咪唑出发,经过还原、氯代、亲核取代反应,合成了N,N’-二烷基膦联咪唑.产物经过了红外、核磁共振及质谱表征.反应前体N,N’-二醇联咪唑和N,N’-二烷基氯联咪唑可作为起始物,合成得到一系列联咪唑衍生物.  相似文献   

7.
溴化四丁铵催化苯乙烯一步合成苯乙烯环状碳酸酯   总被引:1,自引:0,他引:1  
以溴化季铵盐为催化剂, 通过苯乙烯的环氧化和CO2的加成反应一步直接合成出苯乙烯环状碳酸酯, 详细考察了催化剂的用量、氧化剂的种类、反应温度、反应时间和CO2压力等因素对反应主产物收率的影响. 结果表明, 以溴化四丁铵为催化剂, 于80 ℃和1 MPa CO2下反应6 h, 环状碳酸酯的收率达到38%, 这是季铵盐阳离子和亲核性阴离子协同催化的结果.  相似文献   

8.
研究了混合溶剂体系中阴离子分别为BF4-,PF6-,Cl-,Br-和I的14种离子液体对来源于黑布林糖苷酶催化合成红景天苷反应的影响.结果表明,在最佳反应条件下,β-糖苷酶的反应初速度和红景天苷的产率分别为3.3mmol/(L·h)和24.5%.离子液体咪唑阳离子的烷基链长(C2~C10)对β-糖苷酶的活性影响较大,当烷基链长为C6时,糖苷酶表现出较高的催化活性.  相似文献   

9.
以 2-氯-4,6-二硝基-1,3-苯二酚为原料,丙酮为烷基源,氢气为还原剂,研究了在10%Pd/C催化剂上一锅法合成N-单烷基氨基苯酚化合物 4,6-二(异丙基氨基)-1,3-苯二酚的反应工艺. 考察了反应条件如醋酸量、丙酮浓度、氢气压力、催化剂量和反应时间对反应的影响,开发出一条高收率、高选择性制备N-单烷基氨基苯酚化合物的合成路线.  相似文献   

10.
发展了一种无需任何添加剂,在水相中合成烷基硫代酯的绿色方法.以卤代烃与硫代酰胺为原料,在水相中反应4 h,即可以较高收率得到预期产物,并可兼容多种官能团.与传统方法相比,该方法具有实验操作简单、反应绿色高效及原子经济等优点,并且可以实现克级制备,具有较高的应用价值.  相似文献   

11.
多环芳二酐型聚酯亚胺膜的透气性能李悦生,丁孟贤,徐纪平(浙江大学高分子科学与工程研究所,杭州,310027)(中国科学院长春应用化学研究所)关键词聚醚酰亚胺,聚酯酰亚胺,膜,透气性通常的聚酰亚胺加工性能较差,在芳环二酐的苯环间引入醚键等柔性基团后,其...  相似文献   

12.
13.
微量元素与疾病诊断治疗的研究现状及展望   总被引:8,自引:0,他引:8  
对国内外微量元素与疾病的关系及其诊断治疗的研究现状及研究动向进行了综述,包括:微量元素与地方病、癌肿、心血管病、糖尿病、眼病、神经系统病等。参考文献72篇。  相似文献   

14.
A QuEChERS (quick, easy, cheap, effective, rugged, and safe) method for the determination of benazolin-ethyl and quizalofop-p-ethyl in rape and soil by high-performance liquid chromatography-tandem mass spectrometry has been developed in this study. The residue and dissipation of benazolin-ethyl and quizalofop-p-ethyl in rape and soil were determined with the developed method. The half-lives of benazolin-ethyl in rape straw and soil were 3.7–5.1 days and 14.3–26.3 days, respectively. The half-lives of quizalofop-p-ethyl in rape straw and soil were 5.0-6.1 days and 0.3–9.7 days, respectively. The residue of benazolin-ethyl and quizalofop-p-ethyl in rapeseed and soil were below the detection limit (i.e., 0.5?mg?kg?1, the maximum residue level of European Union for quizalofop-p-ethyl).  相似文献   

15.
Herein, we present the synthetic route and the photophysical, electrochemical as well as laser properties of novel red‐emitting boron‐dipyrromethenes (BODIPYs) bearing arylethyne moieties. Such functionality is added along the main axis of the chromophore leading to single‐ and double‐substituted derivatives. The relationship between the dye structure and the lasing properties is studied in detail with the help of the photophysical and electrochemical properties as well as quantum mechanical simulations. The asymmetric substitution of the parent dye induces inhomogeneities in the charge distribution, which leads to an overall loss of the fluorescence capacity, mainly in polar media. Such non‐radiative deactivation processes can be softened by decreasing the electron‐donor ability of the substituent or even avoided by symmetrical substitution. Thus, grafting of the arylethyne moieties at the longitudinal axis of the indacene core results in an effective strategy to develop red‐edge BODIPYs with highly efficient and photostable laser emission.  相似文献   

16.
朱劲波  马立群  梁飞  苗迎春  王立民 《应用化学》2015,32(11):1221-1230
Ti-V基储氢合金在室温、常压下即可表现出良好的储氢特性,且质量储氢容量明显高于传统AB5型储氢合金,从而在氢气的精制和回收、运输和储存及热泵等方面有较早的应用。 此外,在混合气体分离、核反应堆中处理氢的同位素、镍氢电池及燃料电池负极材料等方面也得到了广泛的研究与关注。 基于目前Ti-V基储氢合金的研究现状,概述了该类合金的优势、限制性因素(包括成因)及改性手段。 此外,为了进一步理解Ti-V基合金储氢机理、构建合金组分与储氢特性之间的对应关系,本工作重点围绕Ti-V基储氢合金及其氢化物的结构、组分优化设计展开综述,并对其未来研究方向做出展望。  相似文献   

17.
钒与糖代谢及糖尿病   总被引:1,自引:0,他引:1  
微量元素钒作为生物体内必需元素,经证实有很重要的生理学功能,与机体糖代谢有十分密切的关系,且能降低糖尿病动物模型的高血糖,极有可能被开发为治疗糖尿病的药物。  相似文献   

18.
The monomeric ν(N—H) vibrations of various trisubstituted ureas of the R2UPh type and -thioureas of the R2TUPh type have been studied. The trans—out isomerism in the former and the trans—out—cis isomerism in the latter are discussed from the point of view of steric effect. The monomeric ν(N—H) vibrations of RPhUPh and RPhTUPh are also examined. The single band appearing in the spectrum of both ureas is characteristic of the cis form; this suggests the existence of phenyl—phenyl interaction (the stacking interaction proposed by Galabov et al. [10]). Behavior of ν(N—H) vibrations at several concentrations is shown to be clearly different in the three forms (trans, out and cis). The presence of the cis form is confirmed by solvent effect experiments.  相似文献   

19.
Tyrosol (T) and hydroxytyrosol (HOT) and their glycosides are promising candidates for applications in functional food products or in complementary therapy. A series of phenylethanoid glycofuranosides (PEGFs) were synthesized to compare some of their biochemical and biological activities with T and HOT. The optimization of glycosylation promoted by environmentally benign basic zinc carbonate was performed to prepare HOT α-L-arabino-, β-D-apio-, and β-D-ribofuranosides. T and HOT β-D-fructofuranosides, prepared by enzymatic transfructosylation of T and HOT, were also included in the comparative study. The antioxidant capacity and DNA-protective potential of T, HOT, and PEGFs on plasmid DNA were determined using cell-free assays. The DNA-damaging potential of the studied compounds for human hepatoma HepG2 cells and their DNA-protective potential on HepG2 cells against hydrogen peroxide were evaluated using the comet assay. Experiments revealed a spectrum of different activities of the studied compounds. HOT and HOT β-D-fructofuranoside appear to be the best-performing scavengers and protectants of plasmid DNA and HepG2 cells. T and T β-D-fructofuranoside display almost zero or low scavenging/antioxidant activity and protective effects on plasmid DNA or HepG2 cells. The results imply that especially HOT β-D-fructofuranoside and β-D-apiofuranoside could be considered as prospective molecules for the subsequent design of supplements with potential in food and health protection.  相似文献   

20.
In this work, ferrocene- and ferrocenium-containing salts were employed to modify montmorillonite. X-ray measurements show an increase in the interlayer spacing upon clay modification, which means that the larger and more organophilic cations were inserted into the gallery space of montmorillonite. Attempts to prepare nanocomposites of polystyrene and ethylene vinyl acetate copolymers lead to immiscible systems; the morphology of these systems was elucidated with TEM, XRD and cone calorimetry. The thermal stability of the composites is greater than that of the virgin polymer.  相似文献   

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