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1.
低分子量有机胺的离子色谱法研究   总被引:4,自引:0,他引:4  
周玉芝  邵光  王勺  牟世芬 《色谱》1997,15(3):243-245
 首次应用CS12分离柱对10种低分子量有机胺的离子色谱法进行了研究。采用了有机改进剂(乙腈),优化了色谱条件,建立了C4以下的有机胺的分析新方法。方法简便、快速、灵敏,可同时测定碱金属和碱土金属离子,准确度和精密度均满足分析要求。  相似文献   

2.
有机胺在离子热合成 LTA 型磷酸铝分子筛中的助模板作用   总被引:1,自引:0,他引:1  
 在 1-丁基-3-甲基溴化咪唑 ([bmim]Br) 离子液体中引入有机胺合成了 LTA 型磷酸铝分子筛 (AlPO4-42), 采用热重分析、核磁共振光谱、红外光谱以及荧光光谱对所得晶化产物进行了表征, 并考察了体系的晶化动力学. 结果表明, 有机胺以特定的聚集形态协同离子液体阳离子起到助模板剂的作用, 并填充在 AlPO4-42 分子筛孔道中. 晶化产物随晶化时间的演变表明, 体系中有机胺浓度的变化改变了动力学路径. 高浓度有机胺所形成的聚集体组装周围的无机物种, 促进了 sod 或 lta 笼结构的形成, 并导致立方相的 LTA 骨架晶化.  相似文献   

3.
飞行时间次级离子质谱(TOF-SIMS)结合X射线光电子能谱(XPS)分析了用化学方法清洗后,银片上残留的未知的有机物,结果显示,有机沾污物主要是一些合18~30碳原子,碳链饱和度很高的酮类和酯类化合物;个别有机物可能是硬脂酰胺。这种结构特点使有机物中的C=O基团易于采取氧原子指向基本表面的取向。通过带部分负电荷的氧原子与金属基体镜像力的作用而增强粘附,TOF-SIMS-二维离子像显示有机沾污物在  相似文献   

4.
不同有机胺对合成杂原子Ga—SI—ZSM—5分子筛的影响   总被引:1,自引:0,他引:1  
考察了几种有机铵作引导剂对以水玻璃为硅源、硝酸镓为镓源合成Ga-Si-ZSM-5分子筛的影响。结果表明,合成体系的最佳碱度与有机胺有关,不同有机胺的合成效果相关很大,以正丁胺作引导剂可获得高结晶度的分子筛产物。通过与合成Al-Si-ZSM-5的比较和一些条件试验,探讨了有机胺的作用,并对分子筛的形成过程进行了合理的推测。  相似文献   

5.
该文以高铼酸盐作为高锝酸盐的非放射性结构替代物,结合离子印迹技术的特异性、共价有机骨架(COF)材料的多孔性和酸/热稳定性,通过自由基聚合和季胺化反应,制备出表面离子印迹共价有机骨架(IICOF)材料,并将其应用于实际环境样品中高铼酸根离子的高效捕获.首先利用1,4-二醛基-2,5-二乙烯基苯与1,3,5-三(4-氨苯...  相似文献   

6.
考察了几种有机胺作引导剂对以水玻璃为硅源、硝酸镓为镓源合成Ga-Si-ZSM-5分子筛的影响。结果表明,合成体系的最佳碱度与有机胺有关,不同有机胺的合成效果相差很大,以正丁胺作引导剂可获得高结晶度的分子筛产物。通过与合成Al-Si-ZSM-5的比较和一些条件试验,探讨了有机胺的作用,并对分子筛的形成过程进行了合理的推测。  相似文献   

7.
稀土发光传感器可用于有害的有机小分子胺的检测,然而稀土离子较大的离子半径和不稳定的配位构型,使其在固态下对有机小分子胺实现高灵敏性的发光检测具有一定的挑战。通过在单β-二酮配体上引入胺醇识别基团,使其与稀土铕离子通过配位成功构筑了具有可调控配体内电荷转移(ILCT)性质的单核稀土配合物[Eu(L)3(H2O)2](HL=(2Z)-1-(4-(双(2-羟基乙基)氨基)苯基)-4,4,4-三氟-3-羟基丁-2-烯-1-酮)。配合物的传感研究表明,[Eu(L)3(H2O)2]在弱的亲核作用下对三丙胺等有机小分子胺表现出明显的发光增强响应。  相似文献   

8.
用羧酸处理的笼形聚偕胺肟树脂(RCO2H/ACAO)吸附Pd(Ⅱ)、Ir(Ⅳ)、Pt(Ⅳ)、Ag(Ⅰ)、Au(Ⅲ)离子的能力与羧酸性质有关,巯其乙酸/ACAO树脂对Pd(Ⅱ)、Ir(Ⅳ)和Au(Ⅲ)吸附容量较高,乙二酸/ACAO树脂则对Ag(Ⅰ)和Pt(Ⅳ)离子有稍强的吸附能力。除Pd(Ⅱ)外,RCO2H/ACAO树脂吸附贵金属离子的能力低于笼形聚偕胺肟树脂(CAO)和碱处理笼形聚偕胺肟树脂(BC  相似文献   

9.
用Cyanex272-Span80-甲苯乳状液膜体系研究了铅的迁移行为,确定了铅迁移的适宜条件。在此条件下,许多常见离子如Cu^2+、Co^2+、Ni^2+、Cd^2+等均不迁移,Hg^2+迁移率很低。因此Pb^2+能与这些离子得到快速且完全的分离。这对分析测定及三废处理等工作具有实际意义。  相似文献   

10.
研究了β-氯化萘汞在(ClRh(CO)2)2催化下于六甲磷酰胺溶液中的偶联反应动力学,证明了其反应为二级,求得了偶联反应动力学常数,α-氯代萘汞和α-溴汞代苯乙酸乙酯在相同的反应条件下不发生偶联反应,在α-溴汞代苯乙酸乙酯的偶联反应条件下分离和鉴定有机铑(I)中间体,根据所提出了反应机理,对上述现象进行了讨论。  相似文献   

11.
用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.  相似文献   

12.
Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.  相似文献   

13.
In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.  相似文献   

14.
The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.  相似文献   

15.
The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.  相似文献   

16.
KMnO4-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.  相似文献   

17.
The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.  相似文献   

18.
A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.  相似文献   

19.
Zhanhui Yang  Shiyi Yang  Jiaxi Xu 《Tetrahedron》2017,73(23):3240-3248
Regiospecific and direct imidation of the methyl C(sp3)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.  相似文献   

20.
A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.  相似文献   

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