Thiourea Based Tweezer Anion Receptors for Selective Sensing of Fluoride Ions

Three 3,3＇-di（4-substituted-phenyl）-1,1＇-isophthaloylbis（thiourea） compounds were designed as novel neutral anion receptors, and synthesized by simple steps in good yields. The single crystal structure of receptor 1 shows that a solvent molecule was captured by the host molecule through intermolecular hydrogen bonding. Moreover, it was self-assembled as a supramolecular system for the presence of abundant inter- and intramolecular hydrogen bonding and π-π interactions between phenyl groups. Their application as anion receptors has been examined by UV-Vis and ^1H NMR spectroscopy, showing that they had a higher selectivity for fluoride than other halides. The host and guest formed a 1 ： 1 stoichiometry complex through hydrogen bonding interactions in the first step, then following a process of deprotonation in presence of an excess of F^- in the solvent of DMF.     

多分支中性受体的合成及αω-二羧酸阴离子识别研究

Two new multi-armed neutral receptors 1 and 2 containing thiourea and amide groups were synthesized by simple steps in good yields. Receptors 1 and 2 have a better selectivity and higher association constants for malonate anion than other anions examined by the present work. In particular, distinct color changes were observed upon addition of dicarboxylate anions to the solution of 1 in DMSO. The UV-Vis and fluorescence spectra data indicate that a 1 ： 2 stoichiometry complex was formed between compound 1 or 2 and dicarboxylate anions of shorter carbon chain, and a 1 ： 1 stoichiometry complex was formed between compound 1 or 2 and dicarboxylate anions of longer carbon chain through hydrogen bonding interactions.     

Amide-based Fluorescent Macrocyclic Anion Receptors

Introduction Interest in the selective recognition and sensing of anionic species continues to attract the attention of su-pramolecular chemistry community.1 The importance of anions in chemical and biological process can not be underestimated. It is well known that in nature neutral proteins bind anions only via hydrogen bonding interac-tions.2 Several anion receptors have been constructed from five-membered heterocycle,3 amide,4 (thio) urea,5 since these groups form relatively strong NHanio…     

The hydrogen sulfate recognition properties of azo-salicylaldehyde schiff base receptors

Azo-salicylaldehyde Schiff base-typed receptors containing an acidic H-bond donor moiety were syn-thesized and characterized. The UV-Vis data indicate that these receptors could act as selective col-orimetric sensors for basic anions and acidic species hydrogen sulfate by different color changes in a water-containing medium. The experiment of Brφnsted acid-base reaction by adding the sodium hy-droxide or perchloric acid revealed that the mechanism of recognition of anions might be deprotona-tion/protonation of the OH fragments by interacting with different anions and that the deprotona-tion/protonation process is fully reversible. The deprotonation/protonation of the receptors is respon-sible for the dramatic color change.     

人工合成受体的阴离子识别研究(Ⅳ)——含有酚羟基化合物的设计合成及阴离子识别研究

Novel azine based receptors with phenolic hydroxyl groups have been synthesized and characterized. A remarkable color change was observed from ¹H NMR and UV-Vis titrations upon the addition of fluoride ions to the solution of receptors in DMSO. The addition of chloride, bromide and iodide to the receptors did not induce any change. The UV-Vis data indicate that a 1∶1 stoichiometry complex is formed between receptors and F^-. ¹H NMR titrations and solvation effect confirmed hydrogen interaction between the receptors and anion. Hence, the receptors bearing phenolic hydroxyl groups can act as fluoride ion sensors even in the presence of other hahide ions.     

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.     

Novel Chromogenic Chemosensors for Fluoride Anion Based on 8-Hydroxyquinoline Azo Derivatives

A series of 8-hydroxyquinoline azo derivatives with diverse conjugated structures were synthesized and studied to chromogenicaUy detect anions. All the dyes allowed selective detection for fluoride anion in CH3CN via instant deprotonation of the compounds, which was affirmed by UV-Vis absorption and 1H NMR spectra. The chromogenically responding ability increases as the substituent changes from phenyl to naphthyl or anthryl. This result is likely to be related to the enhancement of intramolecular charge transfer （ICT） induced by extension of conjugated structure.     

Influence of counteranions on catalytic ability of immobilized laccase in Cu-alginate matrices： Inhibition of chloride and activation of acetate

Laccase is a promising oxidase with environmental applications, such as lignin degradation and chlorophenol detoxification. Laccase immobilization can significantly improve physiochemical stability and reusability compared to the free enzymes. In this work, anion effect was investigated in entrapment of Cu-alginate matrix with five types of anions, including perchlorate(ClO4à), nitrate(NO3à), sulfate(SO42à), chloride(Clà), and acetate(CH3CO2à). Accordingly, chloride inhibition and acetate activation were detected in the o-tolidine kinetic experiments, while effects of the other three anions were much smaller. Such counteranion effects were also observed in the laccase-catalyzed biodegradation of 2,4-dichlorophenol. The results indicated that counteranions in the enzyme immobilization process are crucial for catalytic capacity, probably due to the competition with the carboxylate groups in alginate.Our results also imply that these anions might coordinate the copper cations in laccase.     

Impact of an ionic surfactant on the ion transfer behaviors at meso-liquid/liquid interface arrays

The influence of ionic surfactants,cetyltrimethylammonium bromide(CTAB),self-assembled within silica-nanochannels of a hybrid mesoporous silica membrane(HMSM) on simple ion transfer(IT)behaviors at the meso-water/1,2-dichloroethane(W/DCE) interface arrays supported by such a HMSM was investigated by voltammetry for the first time.Significantly,it is found that the CTAB in HMSM can dramatically enhance the peak-current responses corresponding to ITs of some anions and even lower their Gibbs transfer energies from W to DCE,which could be ascribed to an anion-exchange process between anions and the bromide of CTAB associated with partial ion-dehydration induced by the CTAB.This work will provide a new strategy to study anion transfer processes and improve the electroanalytical performance for anion detection at the liquid/liquid interface.     

A High Sensitivity Detection Method of Singlet Oxygen and Superoxide Anion

This paper, for the first time, reports a method that can be used as a highly sensitive probe for singlet oxygen (^1O2) and superoxide anion (O2^-) in vitro or in vivo. FCLA(3,7-dihydro-6-{4-[2-(N‘-(5-fluoresceinyl)thioureido)ethoxy]phenyl}-2-methylimidazo{1,2-a}pyrazin-3-one sodium salt), a chemiluminescence (CL) analysis reagent, has been reported to sensitively react with ^1O2 and O2^- to emit photons with a spectral peak of 525nm. In this work,when human serum albumin (HSA) was added into FCLA solution to enhance the CL intensity,approximately 20 times, compared to that without HSA. The enhanced CL had the same 525 nm spectral peak, identical to that without HSA. By gradually reducing the molecular oxygen content in the solution, we find that the auto-oxidation of oxygen molecules dissolved in the solution plays an important role in the CL process. Based on these experimental evidences, we propose a novel and highly sensitive detection method of ^1O2 and O2^- which may have a great potential in chemical and medical applications.     

苯甲醛缩氨基硫脲对CH_3COO~-和H_2PO_4~-的识别作用

设计合成了受体分子苯甲醛缩氨基硫脲,利用紫外-可见吸收光谱考察了在DMSO中对ClO3-,H2PO4-及CH3COO-的选择性识别作用,当加入H2PO4-或CH3COO-时,溶液颜色立刻由无色转变为黄色,而加入ClO3-阴离子则无变化,从而实现对此2种离子的裸眼检测。通过计算可知,由于阴离子碱性各异,受体分子对2种阴离子的识别作用呈现出有规律的变化,即CH3COO-H2PO4-;且主客体间形成1∶1的配合物。质子溶剂效应实验进一步证明了受体分子与阴离子之间以氢键作用方式相结合。     

含脲苯并咪唑类离子液体的合成及阴离子识别性能

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.     

2-(2′-羟基-3′-甲氧基苯基)-5,6-二硝基苯并咪唑的阴离子识别

设计并合成了2-(2′-羟基-3′-甲氧基苯基)-5,6-二硝基苯并咪唑化合物(1),通过X射线单晶衍射研究了该化合物的固态结构.利用紫外-可见光谱技术研究了其对阴离子的识别,发现化合物1能够在DMSO中对AcO-,H2PO4-,OH-的3种离子进行有效识别,同时溶液由原来的黄色变成红色,实现裸眼检测.     

间苯二甲醛缩双芳氨基硫脲的合成及阴离子识别研究

设计合成了5种间苯二甲醛缩双芳氨基硫脲受体分子, 利用紫外-可见吸收光谱及1H NMR, 考察了其与F-, Cl-, Br-, I-, CH3COO-, HSO-4, NO-3和H2PO-4等8种阴离子的作用. 当在受体分子S0, S1, S2, S3和S4的DMSO溶液中加入F-和CH3COO-四丁基铵盐的DMSO溶液时, 吸收光谱发生显著红移, 溶液颜色由无色变为深黄色, 而加入其它阴离子则无显著变化, 可以实现对这两种阴离子的裸眼检测及光谱分析. 计算结果表明, 随着苯环上取代基的变化, 此5种受体分子对F-和CH3COO-的识别作用呈现规律性变化. 1H NMR 及质子溶剂效应进一步证明了受体分子与阴离子之间以氢键作用方式相结合. Job工作曲线表明, 该类受体分子与阴离子形成1∶1的氢键配合物.     

香豆素衍生物对阴离子的识别特性

用紫外光谱滴定法研究了3种香豆素衍生物与阴离子间存在的特殊识别行为,比较了受体分子结构对阴离子配合物稳定性的影响,以及阴离子浓度对配合物光谱的影响.实验结果表明:受体分子对F^- 、Cl^-、Br^-、Ac^-、H₂PO₄^-、HSO₄^-等不同种阴离子客体的识别能力存在一定差异,受体分子与阴离子通过氢键结合,由于氢键良好的方向性和选择性,对F^-、Ac^-、H₂PO₄^-等有较好的选择性和识别能力,而与其他的阴离子几乎没有作用.     

缩氨基硫脲衍生物受体的合成及阴离子识别研究

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.     

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.     

苯甲酰氨基脲的合成及其阴离子识别

设计合成了N-(取代苯甲酰氨基)脲衍生物(取代基＝p-OC2H5, H, p-Cl) 1～3, 应用吸收光谱法考察了受体分子与阴离子如 , F－, 等的相互作用, 考察了取代基对受体分子与阴离子亲合力和结合选择性的调控或改善能力. 结果表明, 该类受体分子与阴离子通过氢键形成阴离子配合物, 乙腈中受体分子1对F－表现出极高的响应选择性. Job作图法表明1与F－的结合计量比为1∶1, 1H NMR滴定结果为受体分子与阴离子间的氢键作用本质提供了直接证据, 初步探讨了F－响应选择性的原因.     

1,10-邻菲啰啉并咪唑衍生物阴离子受体的合成及识别性能

设计合成了2个1,10-邻菲啰啉并咪唑衍生物阴离子受体2-(2-羟基苯基)-1H-咪唑[4,5-f][1,10]邻菲啰啉(1)和2-(2-羟基-5-溴苯基)-1H-咪唑[4,5-f][1,10]邻菲啰啉(2), 受体2的结构由X射线单晶衍射分析确证. 通过紫外-可见光谱滴定及 ¹H NMR滴定研究了这2个受体对F^-, Cl^-, Br^-, I^-, H₂PO₄^-和AcO^- 6种阴离子的识别传感作用及作用机理. 结果表明, 受体对AcO^-, F^-和H₂PO₄^-有较强的传感作用, 溶液颜色由淡黄色变为黄色; 对Cl^-的作用较弱; 而对Br^-和I^-则无明显作用. 通过机理研究发现, 受体与F^-, H₂PO₄^-和AcO^-形成1: 1的氢键超分子, 当阴离子的量超过受体的1倍以后, 咪唑氮上的氢转移到阴离子; 受体与Cl^-以氢键形成超分子复合物, 而与Br^-和I^-作用很弱.     

一类缩双芳氨基硫脲受体的合成及阴离子识别

缩双芳氨基硫脲;合成;阴离子识别;氢键作用