含氮鎓阴离子受体的研究进展

含氮鎓阴离子受体是目前阴离子识别领域研究的热点之一,此类受体具有主体结构修饰的灵活性和多样性,能更好的发挥氢键、疏水作用、静电作用、π-π作用、阴离子-π作用的协同效应等优点。本文详细评述了咪唑鎓和吡啶鎓两类含氮鎓受体的设计、结构及其阴离子识别作用的研究进展。     

含CH基的阴离子受体

阴离子在生命、临床及环境科学中有着重要作用,设计用于识别阴离子的人工合成受体是超分子化学的一个研究热点。识别阴离子的方法主要有氢键作用、质子转移机制、路易斯酸碱作用、以及基于不可逆的特定化学反应等。相对于传统的含NH或OH识别位点的阴离子受体,近年来含CH基阴离子受体的研究取得了长足的进展。本文详细评述了含烷基CH,苯基CH,三唑CH,咪唑鎓CH,三唑鎓CH以及CHCN基阴离子受体的设计、结构及其阴离子识别作用的研究进展。     

识别磷酸二氢根离子荧光探针的研究进展

分子识别是指主体对客体选择性结合并产生特定功能的过程,是超分子化学研究的重要内容。它包括对中性分子、阳离子和阴离子的识别,其中阴离子识别相对前两者发展较为迟缓,亟待丰富和发展。阴离子识别作为分子识别的一个重要分支,近年来引起了国内外专家学者的广泛关注,聚焦点是合成具有高选择性识别各种阴离子的人工识别受体。磷酸二氢根离子广泛存在于各种生命体中,所以磷酸二氢根的识别在生物医药,环境保护,材料化学等领域的发展进程中起着至关重要的作用。本文总结了一些能与磷酸二氢根特异性结合的受体,这些阴离子识别受体由尿素或硫脲、酰胺、吡咯、咪唑、吡啶等识别单元和发色基团通过共价键连接,并且与H_2PO~-_4主要以氢键结合。     

季戊四醇衍生的咪唑鎓化合物的合成及其对阴离子的光谱响应

咪唑鎓本身带有正电荷,2-位碳氢(C2-H)具有一定的酸性,是一种良好的氢键供体,能与阴离子形成氢键。因此,咪唑鎓可以识别各种无机阴离子和生物体内重要的阴离子。本文利用四(1-咪唑甲基)甲烷的独特结构,通过烷基化反应,合成了多咪唑鎓盐2、含有多功能臂的双咪唑鎓盐3和咪唑鎓环番4。采用荧光发射光谱法研究了咪唑鎓盐2、3、4对阴离子(Cl~-、Br~-、I~-、CH_3COO~-、PhCOO~-、HSO_4~-)的光谱响应。结果表明,咪唑鎓盐2和咪唑鎓环番4a加入Cl~-,荧光强度明显增强;咪唑鎓盐3a加入PhCOO~-,荧光强度明显减弱;咪唑鎓盐3b和咪唑鎓环番4b加入I~-,荧光强度明显增强。     

基于脲衍生物阴离子识别的电化学检测

作为优良的氢键给予体,脲基(-NH-CO-NH-)是构筑阴离子识别受体的理想结构单元.而电化学方法因其方便快捷、灵敏度高等优点,近年来被广泛应用于阴离子的识别检测.本文对脲类受体的电化学阴离子识别进行了讨论,主要包括:(i) 归纳整理了电化学阴离子识别的机理,包括识别位点与阴离子结合之后对氧化还原中心的5种扰动机理和溶液中电化学测试受体和阴离子相互作用时常见现象的分析及对应结合常数的计算; (ii) 电活性脲类阴离子受体的研究进展,包括受体分子的设计、识别和机理; (iii) 探讨了该领域的后续发展方向.     

硫脲类阴离子受体的研究进展

阴离子识别是超分子化学研究的重要内容之一,其关键环节是构筑可识别阴离子的结合受体,后者以非共价键力如静电作用、疏水作用、氢键等与阴离子结合.本文详细评述了近5年来硫脲类阴离子识别受体的设计、结构及其阴离子识别作用的研究进展.     

方酰胺衍生物及其在离子识别中的应用

方酰胺骨架具有芳香性的四元环状刚性结构,作为双氢键受体和双氢键给体能与许多客体物种结合,是一类重要、理想的氢键给/受体单元,同时该类给/受体的功能化设计为离子识别行为的检测提供了方便。本文综述了近年来方酰胺化合物的结构特性、衍生化方法,及其在超分子中对阴离子、阳离子与两性离子的识别,实现对离子的跨膜传输、分离与萃取、凝胶响应等功能,以及其在有机小分子催化反应中稳定离子型中间体实现对反应底物催化的功能,并展望了方酰胺化合物在离子识别中的发展前景。     

基于光化学传感器的二元羧酸阴离子识别研究进展

二元羧酸阴离子的识别与检测是当前超分子化学研究的热点领域之一。普遍使用的基于光学信号的二元羧酸阴离子受体主要有基于氢键作用的中性受体、有机阳离子型受体和金属配合物型受体三种类型。本文按照受体与二元羧酸阴离子作用类型的不同,介绍了近年来基于光化学传感器的二元羧酸阴离子的识别研究进展,并对相关研究进行了展望。     

含氮杂环类阴离子受体*

含氮杂环类阴离子受体是目前超分子阴离子识别领域研究的热点之一。此类受体具有主体结构丰富、可调节性强、识别范围广、选择性强、灵敏度高等优点。本文综述了以吡咯、吲哚、咪唑、吡唑等含氮杂环为识别基团的阴离子受体的设计原理、识别性能和机理,展望了该领域的发展方向。     

新型脱氧胆酸钳形阴离子受体的设计合成及其对阴离子的识别性能研究

具有对阴离子选择性识别的人工受体的设计合成是生物有机化学和超分子化学前沿富于挑战性的领域之一[1].在许多识别阴离子的人工受体化合物中,脲和硫脲衍生物是重要的中性受体化合物之一.     

Influence of the size and geometry of the anion binding pocket of sugar–urea anion receptors on chiral recognition

Three new chiral urea-type anion receptors were synthesized from aromatic diamines and 1-amino-1-deoxyglucose. The anion binding properties of these receptors were studied using chiral carboxylates derived from mandelic acid and three α-amino acids. We found that the size of the anion binding pocket played an important role in chiral recognition processes. The best results were obtained for 1,8-diaminoanthracene and α-amino acid anions.     

Efficient Amide Based Halogenide Anion Receptors

In this paper, we present the synthesis and anion recognition properties of the amide based phenanthroline derivatives 1, 2 and 3. In all cases 1:1 receptor : anion complexes were observed. The receptors were found to be selective for fluoride and chloride respectively over other putative anionic guest species.     

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.     

Pyrrolic and polypyrrolic anion binding agents

This review traces the emergence of pyrrole-based receptors for anion recognition. It outlines how serendipitous findings that the diprotonated form of sapphyrin, a pentapyrrolic expanded porphyrin, formed a centrally-bound complex with fluoride anion made over a decade ago spawned studies of this and other expanded porphyrins as receptors, carriers, and sensors of anions. Further evolutions of the field, including in particular the finding that neutral, non-aromatic oligopyrrole macrocycles, such as the calixpyrroles and calixphyrins, can act as cheap, and easy-to-prepare anion receptors will also be highlighted, as will recent work with acyclic systems, including dipyrrolylquinoxalines (DPQs) and simple derivatives of pyrrole itself.     

Unique fluoride anion complexation in basic media by 5,5-dioxophenothiazine bis(phenylurea) and bis(phenylthiourea)

The anion recognition properties of the newly synthesized 5,5-dioxophenothiazine bis(phenylurea) and bis(phenylthiourea) were investigated in acetonitrile using UV–vis spectroscopy. While most of the studied anions were bound only by the neutral receptors, fluoride and acetate were complexed even by the deprotonated ones.     

Triazole-based chromogenic and non-chromogenic receptors for halides

We designed and synthesized a series of triazole-based receptors for anion recognition. Our studies demonstrated that an amide-linked triazole unit is a promising moiety for anion recognition. We synthesized various chromogenic and non-chromogenic receptors based on this moiety. Receptor 11 binds very strongly (K = 102,750 M⁻¹) to fluoride. Receptor 18 changes color from faint yellow to orange upon binding to fluoride.     

Synthesis and anion recognition properties of pyrrole-bearing acyclic receptors

A new series of acyclic anion receptors (1-4) based on methyl 5-(aminomethyl)-1H-pyrrole-2-carboxylate were designed and synthesized. The anion recognition properties of these receptors were examined by ¹H NMR spectroscopy and rationalized by density functional theoretical calculation. Receptor 1 displays the highest affinity and selectivity for anionic guests mainly due to the intramolecular hydrogen bonds and rigid molecular geometry.     

Homochiral tripodal imidazolium receptors: structural and anion-receptor studies

Two homochiral tripodal receptors were characterised by X-ray crystallography, the first examples for this class of imidazolium receptor. These receptors were also screened for anion recognition. Both receptors demonstrated selectivity towards chloride and bromide with binding constants as high as 16,000.     

Synthesis, structure and the binding properties of the amide-based anion receptors derived from 1H-indole-7-amine

Indole-7-amine was investigated as an alternative to aniline in construction of amide-based anion receptors. Replacement of aniline with indolamine introduces additional binding site—indolyl NH, which can enhance anion binding for more than five times. The molecular modelling of indole-containing receptors revealed the correlation between their conformational preferences and their affinity towards anions.