基于分子内电荷转移的阴离子比率荧光分子探针

设计合成了一种基于4-甲基-1-羟基二苯甲酮对硝基苯腙的比色和比率荧光阴离子受体1。此类受体以羟基和腙单元为识别位点,以硝基苯基为信号报告基团。向受体1的DMSO溶液中加入AcO-、H2PO4-、F-后,溶液颜色由黄色变为紫红色,而加入所研究的其它阴离子则无变化,从而实现对AcO-、H2PO4-、F-这三种离子的裸眼识别。利用紫外-可见吸收光谱、荧光光谱考察了其与AcO-,H2PO4-,F-,Cl-,Br-,I-等阴离子的识别作用。1H NMR滴定为受体分子与阴离子之间氢键作用本质提供了有力证据。     

芳酰基硫脲受体的合成及对阴离子识别研究

设计合成了3种芳酰基硫脲受体分子. 利用紫外-可见吸收光谱考察了其与F^－, Cl^－, Br^－, AcO^－, HSO₄^－, H₂PO₄^－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^－, AcO^－时, 溶液立刻由无色变为黄色, 而加入其它阴离子则无变化, 从而实现对这两种阴离子的裸眼识别. 结果表明受体分子与阴离子间形成1∶1型的配合物. 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.     

基于含偶氮酚羟基席夫碱新型简单比色传感器

A novel N-(2-hydroxy-5-chlorodibenzophenone)-N0-[2-hydroxy-5-azophenyl-benzaldehyde]-1,2-diaminobenzene receptor has been synthesized by simple steps with good yields. The anion recognition properties were studied by ultraviolet-visible spectroscopy. The resultsshowed that the receptor had a higher affinity to F^-, AcO^-, and H₂PO₄^-, but no evident binding with Cl^-, Br^-, and I^-. Upon addition of the three former anions to the receptors in DMSO, the solution exhibited an obvious color change from colorless to yellow, which could be observed by the naked eye, thus the receptor could act as a fluoride ion sensor even in the presence of other halide ions. The UV-Vis data indicates that a 1:1 stoichiometric complex is formed through hydrogen bonding interactions between receptor and anions.     

A novel neutral receptor for selective recognition of H2PO 4 −

A new urea-based receptor was designed to selectively recognize H₂PO₄⁻ among other anions (such as F^-, Cl^-, Br^-, I^-, OH^-, AcO^-) in organic solvent (DMSO) through intermolecular hydrogen bonding. Addition of anions to the receptor caused changes in UV–vis spectrum which provided the first indication of its anion binding ability. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Anion Recognition Using Novel and Colorimetric Tweezer Receptors:1,3-Phenylenedi(carbonylhydrazone) in Aqueous-organic Binary Solvents

本文设计合成了2种新型的间苯二甲酰腙类钳形受体。在DMSO和DMSO-H2O混合溶液中,通过紫外可见光谱分别考察了受体分子3a对F-, Cl-, Br-, I-, AcO-, HSO4-, H2PO4-和ClO4-的相互作用。结果表明,在DMSO溶液中,受体3a对F-,CH3COO-和H2PO4-有显著识别效果,溶液颜色由无色变为黄色,实现裸眼检测。在15%H2O-85%DMSO含水体系中,3a可高选择性识别CH3COO-。1H NMR滴定表明过量F-的加入使受体分子3a发生脱质子作用,探讨了主客体之间的作用机理。并直接用于水相中无机醋酸盐的直接显色检测。     

Colorimetric anion chemosensor based on 2-aminobenzimidazole: naked-eye detection of biologically important anions

We synthesized a novel colorimetric anion chemosensor bearing benzimidazole motifs as recognition sites in the pods of the receptor. The addition of tetrabutylammonium salts of F⁻ or AcO⁻ to the solution of receptor caused dramatic color changes from colorless to yellow, which was clearly visible to the naked eye. The receptor showed no significant changes on addition of other anions such as Cl⁻, Br⁻, I⁻, NO₃⁻, and H₂PO₄⁻.     

Efficient fluoride-selective receptor: experiment and theory

A novel artificial receptor, (3′-nitrobenzo)[2,3-d]-(3′′-nitrobenzo)[9,10-d]-1,4,8,11-tetraazacyclotetradecane-5,7,12,14-tetraone, has been synthesized and shows high selective and recognitive ability for F^- among F⁻, Cl⁻, Br⁻, AcO⁻, H₂PO₄⁻ by UV-vis and ¹H NMR titration experiments. Theoretical investigations suggest that the fluoride selectivity among various anions comes from the fact that the fluoride approaches much closer to the amide protons than other anions located above the cavity. The interaction energies support the large binding ability difference between F⁻ and Cl⁻/Br⁻/AcO⁻/H₂PO₄⁻.     

Urea-based polyacetylenes as an optical sensor for fluoride ions

Novel acetylenes carrying urea groups, 1-(4-ethynylphenyl)-3-(4-nitrophenyl) urea (1), 1-(4-propargyl)-3-(4-nitrophenyl) urea (2), were synthesized and polymerized with rhodium catalyst. Polymers [poly(1) and poly(2)] with moderate molecular weights were obtained in good yields. The anion sensing ability of poly(1) and poly(2) was estimated using the tetra-n-butylammonium (TBA) salts of a series of anions in DMF. Upon the addition of F-, the color of the DMF solution of poly(1) and poly(2) immediately turned to a different color, while the color of solution changed slightly upon addition of Cl-, HSO4-, Br-, and NO3-, indicating the F- sensing ability of poly(1) and poly(2). The 1H-NMR titrations of poly(1) revealed that the colorimetric response of poly(1) was triggered by the urea/F- interaction through the hydrogen bonding and/or deprotonation process. The absorption spectra titration and Hill plot analysis were carried out to measure the F- binding ability, and the Hill coefficient in the poly(1)/F- complexation was found to be 5.8. This result clearly indicated that this binding mode between poly(1) and F- was based on a positive homotropic allosterism.     

Novel N,N＇-Diacylhydrazine-Based Colorimetric Receptors for Selective Sensing of Fluoride and Acetate Anions

Three novel and simple N,N＇-diacylhydrazine-based colorimetric receptors have been prepared. The binding properties of the receptors to anions such as F^-, Cl^-, Br^-, AcO^-, HSO4^- and HEPO4^- in acetonitrile solution were examined by UV-Vis spectroscopy methods, which show high sensitivity and selectivity to F^- and AcO^- over other anions. The results indicated that a 1 ： 1 stoichiometry complex was formed between the receptors and the anions, while ^1H NMR titrations confirmed hydrogen binding interaction between the receptors and the anions.     

Synthesis of Novel Anionic Receptors with （Thio）urea and Amide Binding Sites and the Recognition Properties for Anions

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

An efficient novel receptor for sensing acetate

A novel highly sensitive colorimetric receptor 1 for acetate based on N-(4-oxa-3-one-phenanthrene-2-carbonyl)-p-nitrophenylhydrazine was designed, synthesized and characterized. Experiments showed that the receptor 1 can selectively recognize acetate in DMSO solution and aqueous solution. The ability of recognition and the bond between receptor 1 and anions were determined using visual inspection, UV?CVis analyses and ¹H NMR experiments. In particular, the UV?CVis analyses showed the whole process included two stages: in the first step, the hydrazine form of 1 interacted with acetate through hydrogen bonding with an obvious color change from yellow to purple upon addition of a small amount of AcO^?. In the second step, as increasing the addition of AcO^?, the color changed from purple to deep yellow, which displayed the deprotonation of the receptor 1.     

Synthesis, optical and electrochemical properties of new receptors and sensors containing anthraquinone and benzimidazole units

Novel anion receptors and sensors, HBIMANQ and BIMANQ fabricated from the imidazolole unit and anthraquinone moieties were synthesized. ¹H NMR spectroscopy and UV-vis titrations in DMSO-d₆ and DMSO, respectively, showed that both receptors underwent deprotonation at the NH- moiety of the amide-anthraquinone unit in the presence of basic anions such as F⁻ and AcO⁻. These phenomena gave a dramatic color change due to charge transfer transition corresponding to the shift of λ_max from 371 nm to 489 nm. Redox chemistry of HBIMANQ and BIMANQ in the presence of anions (F⁻, Cl⁻, AcO⁻, BzO⁻, and H₂PO₄⁻) using cyclic voltammetry showed the different CV responses upon addition of various anions. In the case of HBIMANQ with various anions, the CV changes are dependent on the basic strength of anions in order of F⁻>AcO⁻, BzO⁻>H₂PO₄⁻>Cl⁻, Br⁻. Interestingly, the CV responses of BIMANQ with H₂PO₄⁻ exhibited the most significant changes. BIMANQ, thus, has an excellent electrochemical selectivity toward H₂PO₄⁻.     

Synthesis of a Phenylhydrazone‐based Colorimetric Anion Sensor with Complementary IMP/INH Logic Functions

A dinitrophenyl hydrazone colorimetric anion sensor (receptor 1 ) was synthesized and its recognition properties towards various anions were investigated by naked eye observation and spectroscopic methods, namely UV‐vis and ¹H NMR titrations in DMSO. The addition of AcO^?, F^? and H₂PO₄^? to receptor 1 resulted in marked red shift of the charge‐transfer absorbance band (Δλ=91 nm, 407 nm to 498 nm) concomitant with a 'naked‐eye' detectable colour change from yellow to pink. However, both the colour and spectral changes were reversible by the addition of cations (M^II) of 3d^5‐10 as well as Cd^II, Hg^II, Mg^II and Ca^II. Subsequently, complementary IMP/INH logic functions based on colour and spectral switching (ON/OFF) were affirmed. The sensor can, thus be utilized as a colorimetric molecular switch modulated by F^?/M^II.     

Selective “naked-eye” sensing of acetate ion based on conformational flexible amide-pyridinium receptor

A simple pincer-shape anion receptor L1 containing amide-pyridinium as binding unit was synthesized and its anion binding properties were investigated by UV–Vis, NMR titration spectra and molecular simulation. L1 displayed better affinity toward AcO^? ion with visible color change compared with other investigated anions, including F^?, H₂PO₄ ^?, Cl^?, Br^?, I^?, NO₃ ^? and HSO₄ ^? ions. The selectivity was ascribed to the synergistic effects arising from hydrogen bonding, electrostatic interaction and induced-fit process.     

Tunability of anion binding strength based on acyl-thiourea receptors containing isatin group

Some acyl-thiourea derivatives containing isatin group were synthesized and their interactions with anions were investigated using UV–vis spectroscopy and ¹H NMR titrations in DMSO and DMSO-d₆, respectively. These compounds have a same molecular framework, functionalising with different groups lead to different anion binding strength of these receptors. Receptor 1 showed a higher binding affinity for AcO⁻ than for F⁻, due to the cooperative multiple hydrogen bond interactions of AcO⁻ with the acyl-thiourea group and N–H group in the indole unit of receptor 1. Displacing the N–H proton in the indole unit with –CH₃ group, receptor 2 showed no obviously discriminative responses for F⁻, AcO⁻ and H₂PO₄⁻ due to lack of such additional binding. In the case of receptor 3, which was functionalised with strong electron-withdrawing group, it showed selectively chromogenic response for F⁻ based on double deprotonation of the receptor in DMSO, whereas AcO⁻ and H₂PO₄⁻ induced single deprotonation only.     

新型呋咱阴离子探针的合成、晶体结构及性质研究

设计合成了一种AcO-和F-的阴离子比色/荧光探针4-氯-7-硝基-2,1,3-苯并呋咱(NBD-Cl)衍生物。探针结构经X-ray单晶衍射测定属于三斜晶系、空间群为P1。用紫外-可见吸收及荧光光谱研究了其识别性能。探针的乙腈溶液加入AcO-,F-后,在较短时间内裸眼能观察到颜色由橘黄色变为红色,同时有显著的荧光增强。核磁滴定及质子溶剂实验证明识别过程为探针与阴离子之间形成的氢键作用力,伴随着质子化过程发生。     

钳形酰腙类阴离子受体的合成及识别性质研究

设计合成了基于吲哚酰腙单元的钳形阴离子受体(1),UV-Vis滴定实验表明,它在含1%DMSO的CH3CN溶液中能选择性识别具有重要生物学意义的F-、Ac O-和H2PO4-(结合比均为1∶1且Ka104L/mol),但对Cl-、Br-、I-、NO3-、N3-、HSO4-和Cl O4-无识别作用。与它相比,端基为苯并呋喃的参照化合物2在同样溶剂中对上述3种阴离子的亲和性减弱,尤其是对H2PO4-。核磁滴定实验表明,受体1中的吲哚环NH和酰胺NH能产生协同效应,从而对阴离子产生了强效键合作用。     

酰腙类化合物的合成和阴离子识别研究

本文设计合成了3种新型的酰腙类受体分子。利用紫外-可见吸收光谱及 ¹H NMR考察了其与F^-、Cl^-、Br^-、I^-、CH₃COO^-、HSO₄^-、NO₃^-等阴离子的作用。结果表明，该类受体分子能较好地识别阴离子F^-和CH₃COO^-，在DMSO溶液中主客体之间形成氢键加合物。尤其对于受体3(间苯双对硝基苯氧乙酰腙)，加入F^-和CH₃COO^-时，溶液颜色有明显变化，受体3对这两种阴离子可实现裸眼识别。     

A colorimetric tetrathiafulvalene-calix[4]pyrrole anion sensor

The interaction and colorimetric sensing properties of a tetrathiafulvalene substituted calix[4]pyrrole sensor with anions were investigated using ¹H NMR and absorption spectroscopic techniques. Visual color changes were observed upon addition of different anions (Cl⁻, Br⁻, CN⁻, and AcO⁻) to a solution of the sensor.     

Color response of tri-armed azo host colorimetric sensors and test kit for fluoride

Five new chromogenic tripodal receptors (2a-e) containing electron withdrawing and donating groups appended to the azophenol moiety were synthesized, characterized, and their chromogenic behaviors toward various anions were investigated. These tripodal receptors showed a distinct color change only when treated with fluoride ions in CH₃CN solution. Yet, other anions such as Cl⁻, Br⁻, I⁻, NO₃⁻, ClO₄⁻, AcO⁻, HSO₄⁻, and H₂PO₄⁻ could not cause any color change. Thus, the receptors 2a-e can be used as a colorimetric chemosensor for the determination of fluoride ion. In addition, ¹H NMR experiments were carried out to explore the nature of interaction between tripodal receptors and fluoride. Finally, analytical application and the use of test strip of the receptor 2b to detect fluoride was also reported.