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The development of anion receptor has attracted increasing interest in supramolecular chemistry, due to poten tial applications in clinical diagnosis, environmental monitoring and biological process. [1] In comparison with thelarge variety of ligands that have been described for cations, [2] the development of selective artificial receptors foranion is still very limited. [3] Two new neutral anion receptors (1 and 2) containing thiourea and amide groups weresynthesized as shown in Scheme 1.  相似文献   

3.
新型硅磷酸铝分子筛CHSAPO-7的合成与性能研究   总被引:1,自引:0,他引:1  
用水热法在二异丙胺-Al2O3-P2O5-SiO2-H2O体系中合成了新型硅磷酸铝分子筛CHSAPO-7。所得样品用X射线粉末衍射和红外光谱分析进行了表征。电子探针能谱分析表明,Si原子存在于分子筛的晶体骨架上。测定了CHSAPO-7的化学组成,研究了它的晶体形貌、吸附性能和热稳定性,同时考察了二异丙胺用量、反应混合物的初始pH值等合成条件对产物结晶相的影响。  相似文献   

4.
一类缩双芳氨基硫脲受体的合成及阴离子识别   总被引:2,自引:0,他引:2  
缩双芳氨基硫脲;合成;阴离子识别;氢键作用  相似文献   

5.
设计并合成了含脲苯并咪唑离子液体受体分子1~3, 利用紫外-可见光谱、 荧光光谱和 1H NMR滴定研究了其对F-, Cl-, Br-, I-, CH3COO-, HSO4-, H2PO4-等阴离子的识别性能. 紫外-可见光谱研究发现, 受体分子1~3可选择性地识别F-, 并形成1: 1型主客体配合物; 荧光光谱研究发现, 受体分子1~3对碱性阴离子有较好的识别作用, 主客体结合常数的顺序为H2PO4->CH3COO-≈ F->HSO4- ≈ Cl->Br- ≈ I-; 1H NMR滴定研究发现, 该类受体分子以咪唑2位CH和脲基NH与阴离子通过氢键结合, 但高浓度的F-会导致受体分子发生脱质子作用.  相似文献   

6.
缩氨基硫脲衍生物受体的合成及阴离子识别研究   总被引:18,自引:3,他引:18  
利用简便的方法设计合成了三种缩氨基硫脲衍生物受体分子. 利用紫外-可见吸收光谱及1H NMR考察了其与 F, Cl, Br, I, CH3COO, C3H7COO, ClO4, NO3等阴离子的作用. 结果表明, 该类受体分子与阴离子形成氢键配合物, 加入F, CH3COO, C3H7COO时, 溶液颜色由无色转变为黄色, 而加入其它阴离子则无变化, 从而实现对这三种阴离子的裸眼检测. 通过计算可知, 同种受体分子对此三种阴离子的作用为F>C3H7COO>CH3COO. 随着苯环上取代基的变化, 此三种受体分子对三种阴离子的作用呈现出有规律的变化, 即o-F取代的受体分子对阴离子的识别作用大于其它两种受体分子, 且主客体间形成1∶1的配合物. 1H NMR滴定及质子溶剂效应为受体分子与阴离子间的氢键作用本质提供了直接依据.  相似文献   

7.
林旭聪  谢增鸿  郭良洽  陈国南 《合成化学》2003,11(6):499-502,506
由二茂铁经甲酰基化、氧化和酰氯化制备的1,1′-二茂铁二酰氯与对苯二胺和对硝基苯胺缩合反应,合成了新型磷酸盐敏感试剂:1,1′-二[(对苯二胺基)-N-羰基]-二茂铁(L1)和1,1′-二[(对硝基苯胺基)-N-羰基]二茂铁(L),并研究了Ll,L2与磷酸盐阴离子的电子结合性能。Ll,L2对磷酸盐响应灵敏。Ll对H2PO4^-响应的线性为1.00μg/mL~10.00μg/mL,检测限(3σ/k)为0.01μg/mL;也对PO4^3-响应的线性为6.60μg/mL~54.50μg/mL,检测限(3σ/k)为0.03μg/mL。  相似文献   

8.
Arjunolic acid, a functionally rich chiral triterpenoid with a rigid pentacyclic backbone, has the potential to be used as a structural framework for the design of molecular receptors and supramolecular architectures. The design and synthesis of the first arjunolic acid-derived 18-crown-6 and its binding studies with metal and tert-butylammonium ions are reported.  相似文献   

9.
ThesystemsconsistingofafluorophorelinkedtoacrownethermoietyareeXtensivelyinvestigated'-'.Sincedrasticchangesintheirphotophysicalpropertiescanbeobservedbycomplexationwithion,theycanbeusedforionicdetection"'.Recentreportsfocusonazamacrocyclicderivativeswithfluorophores"',inwhichthefluorophoreandcrownethermoietywerelinkedvianitrogenatom.Thepresenceofabasicnitrogenatomwhichiseasytobeprotonatedleadstoelthancementoffluorescencequantumyield""'.Wereplacedthenitrogenatomofthecrownbyoxygenwhichisexpect…  相似文献   

10.
IntroductionSincemoreandmoreanionsplayanimportantroleinbiologicalandchemicalprocesses ,thedesignandsynthe sisofreceptorsforon lineandrealtimedetectionofbio logicallyimportantanions ,andforenvironmentalmonitor ingofharmfulanionpollutantshaveattractedparticularat tentioninsupramolecularchemistry .1Thebasicstrategyfortheconstructionofanion bindingreceptorsistoexploitthereceptorsthathaveelectrostatic ,2 hydrogenbonding ,3orLewisacidiccentralinteraction .4 Amongavarietyofnon covalentinteractions ,h…  相似文献   

11.
基于题示光敏离子载体MMC-MAC(O5)与金属离子配位时荧光或延迟荧光性质的变化,研究了它作为光敏主体在乙腈或水溶液中对Li+,Na+,K+,Mg2+,Ba2+和Pb2+离子的识别性能,由改进的H-B方程计算得主客识别的稳定常数和敏感因子.结果表明,由于该光敏离子载体的香豆素的羰基能以七元环形式参与对金属离子的配位,在一定程度上增大了对客体离子的络合能力;在水溶液中,由于金属离子的溶剂化作用和因香豆素的羰基易与水形成氢键,影响了MMC-MAC(O5)与客体离子的结合,稳定常数明显降低.基于MMC-MAC(O5)的分子结构和与金属离子结合时荧光强度的增强,讨论了识别机理  相似文献   

12.
The dibenzo[3n]crown-n were synthesised starting from bis[2-(o-hydroxyphenoxy)ethyl]ether obtained from bis[2-(o-formylphenoxy)ethyl]ether via Baeyer-Villiger oxidation in H2O2/CH3COOH in a good yield. The cyclic condensation ofbis[2-(o-hydroxyphenoxy)ethyl]etherwith tri- and tetraethylene glycol bisdichlorides andthe bisditosylate of pentaethylene glycol in DMF/Me2CO3 afforded the large cyclic ethers of dibenzo[21]crown-7, dibenzo[24]crown-8 and dibenzo[27]crown-9. The structures were analysed with IR, 1H NMR, 13C NMR and low-resolution mass spectroscopy methods. The Na+, K+, Rb+ and Cs+ cations' recognition of the molecules were conducted withsteady-state fluorescence spectroscopy. The 1:1 association constants, Ka, in acetonitrile were estimated. Dibenzo[21]crown-7 was the best both for K+ and Rb+ binding but showed too small an effect on Cs+. Dibenzo[24]crown-8 exhibited the binding power in the order of Rb+ > K+ > Na+ > Cs+. However, dibenzo[27]crown-9 displayed marked binding with only K+ but not with Rb+ or with Cs+ cations probably due to the heavy atom effect of fluorescence quenching.  相似文献   

13.
The copolymerization of ethylene and 5-ethylidene-2-norbornene (ENB) catalyzed by metallocene catalysts system is reported in this paper. The catalysts include Et(Ind)2 ZrCl2/MAO and Cp2ZrCl2/MAO. The resulting copolymer contains an ethylidene group which can be readily converted to a hydroxyl group by hydrogen borane. Then the hydroxyl group in turn can be utilized for grafting with ?-caprolactone. The dependence of the graft weight percentage on the reaction time was also studied. The graft copolymer is a compatibilizer for various polyethylene blends with engineering plastics. A functional polyethylene can be easily synthesized by the copolymerization of ethylene and 9-decen-l-ol using a homogeneous catalytic system of El(Ind)2ZrCl2/MAO. The resulting functional polyethylene was characterized by NMR, DSC, IR and TGA; and can also be utilized for grafting with ?-caprolactone. The grafted copolymer is also an effective compatibilizer.  相似文献   

14.
Russian Journal of Organic Chemistry - Recyclization of 4-oxo-1,3-benzoxazinium perchlorates under the action of hydrazinobenzoic acids gave previously unknown 1,2,4-triazolylbenzoic acids which...  相似文献   

15.
Synthetic carbohydrate receptors (SCRs) that selectively recognize cell-surface glycans could be used for detection, drug delivery, or as therapeutics. Here we report the synthesis of seven new C2h symmetric tetrapodal SCRs. The structures of these SCRs possess a conserved biaryl core, and they vary in the four heterocyclic binding groups that are linked to the biaryl core via secondary amines. Supramolecular association between these SCRs and five biologically relevant C1-O-octyloxy glycans, α/β-glucoside ( α/β-Glc ), α/β-mannoside ( α/β-Man ), and β-galactoside ( β-Gal ), was studied by mass spectrometry, 1H NMR titrations, and molecular modeling. These studies revealed that selectivity can be achieved in these tetrapodal SCRs by varying the heterocyclic binding group. We found that SCR017 (3-pyrrole), SCR021 (3-pyridine), and SCR022 (2-phenol) bind only to β-Glc. SCR019 (3-indole) binds only to β-Man. SCR020 (2-pyridine) binds β-Man and α-Man with a preference to the latter. SCR018 (2-indole) binds α-Man and β-Gal with a preference to the former. The glycan guests bound within their SCR hosts in one of three supramolecular geometries: center-parallel, center-perpendicular, and off-center. Many host–guest combinations formed higher stoichiometry complexes, 2:1 glycan⋅SCR or 1:2 glycan⋅SCR , where the former are driven by positive allosteric cooperativity induced by glycan–glycan contacts.  相似文献   

16.
以咔唑、三苯基氯硅烷及2-溴芴为原料,经甲基化、硼酸化、Ullmann偶联、Suzuki偶联等反应合成了两种新型咔唑衍生物--3,6-二(9,9-二甲基-9H-2-芴基)-9-苯基-9H-咔唑(1a)和3,6-二[(4-三苯硅基)苯基]-9-苯基-9H-咔唑(1b),其结构经1H NMR和元素分析表征.用UV-Vis,荧光光谱和循环伏安曲线研究了1a和1b的光电性能.  相似文献   

17.
以二茂铁甲醛和三羟甲氨基甲烷为原料,经缩合,脱水和还原反应合成了两种新型的二茂铁衍生物,其结构经1H NMR, IR和MS表征,并利用循环伏安法研究了它们的电化学性质.  相似文献   

18.
两种新碗形分子的合成及其纤维状晶的研究   总被引:1,自引:0,他引:1  
以香兰素为原料,采用三聚法合成了2种外围脂肪族基团碳数分别为3和5的环三亚藜芦基(cyclotriveratrylene,CTV)系衍生物碗形分子--CTV-3和CTV-5,其中,用先关环后衍生化的合成路线克服了因CTV-5的外围基团太长、分子对称性不好而无法用传统方法合成的难题.产物的化学结构经1H NMR、13CNMR、质谱以及元素分析确认.在偏光显微镜下观察到纤维状晶叠加在碗形分子的向列液晶织构上.纤维状晶是从液晶态冷却时形成并装饰在原液晶织构上的一种结晶形态.通过SEM测定,观察到纤维状晶实际上是由厚度约为100-200m、宽度为2-5μm的无限长的单层片晶组成的多层片晶,而片晶则是由直径约为100nm的微纤组成的.微纤可以推断是碗形分子柱的束状聚集体.  相似文献   

19.
Two novel triphenylene-aminoanthraquinone dimers 4a and 4b were synthesized by reacting triphenylene carboxyl derivatives 3a or 3b with 2-aminoanthracene-9,10-dione in yields of 80% and 78%, respectively. Their structures were confirmed by 1H NMR, electrospray ionization (ESI-MS), and elemental analysis. Their mesomorphic properties were studied by diffraction scanning calorimetry (DSC), polarizing optical microscopy (POM), and x-ray diffraction (XRD). The mesomorphic results suggested that they possess excellent mesophase properties. The investigation of fluorescence properties indicated that the strong cooperating fluorescence actions exist between two structural units. The fluorescence of dimers 4a and4b are seriously quenched due to the electron transfer from donor (triphenylene unit) to acceptor (aminoanthraquinone unit).  相似文献   

20.
Three hexakis(imidazole)metallo complexes of Co, Cd and Ni were synthesized and spectroscopically characterized. The crystal and molecular structures have been determined by X-ray crystallography analysis. The metal ions have an octahedral geometry with the MN6 chromophore. The electrochemical experimental results indicate that both [Co(Im)6]C12·2HCl·2H2O (1) and [Ni(Im)6]C12·4H2O (3) [Im=imidazole] could interact with DNA mainly by intercalation.  相似文献   

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