The Synthesis And Anion Recognition Of Ferrocenyl Imidazolium Salt And Lewis Phenylboronic Acid Receptors

Anion is widespread in real word and plays a very important role in the fields of chemistry,medicine,and the environment,etc.Thus the design and synthesis of specific anion selective identification and sensing effect of artificial receptors have caused wide interest of researchers.In recent years,considerable attention has been paid for the identification sensing and detecting problems of anion such as F-which has influence on life and environment.However,F-as the smallest anion,and its characteristics with strong electronegativity and hydrophilicity have brought some difficulties in fluoride recognition.Therefore,we have tracked current anion(F-)identification of hot spots in this dissertation.A series of receptors have been designed based on ferrocene unit,and recognition sites such as imidazolium salt,and Lewis boron-containing group.The recognition behavior of receptors and fluoride ion have been studied by using electrochemistry,UV,and NMR titration methods.Further the mechanism of recognition of receptors and fluoride ion have been investigated.The major contents are as followed.1.Design and synthesis of hydrophilic biferrocene imidazolium salt receptors.The water-soluble aspect of receptors has been raised by introducing hydrophilic group such as sulfonate,oligomeric ethanol.The nature of the receptors and anion was detected and identified by using electrochemistry such as cyclic voltarmmetry.Two pairs of redox peaks of receptors had merging into one upon the addition of F-and H2PO4-.IH NMR titration showed that the interaction between receptors and anion was mainly based on(C-H)+…X-type ionized hydrogen bonds,meanwhile the C-2 proton of imidazolium had the trend of downfield shift,even disappearance.And the excess F-promoted the deprotonation of receptors,with the phenomenon of a triplet in 16 ppm which had been proved to be HF2-.2.Design and synthesis of ferrocenyl benzimidalium salt receptors.Their crystal structures revealed that the receptors were linked by C-H …F hydrogen bonds.The anion recognition behavior had been studied by electrochemistry such as cyclic voltammetry,and UV-vis,respectively.The receptors had significant responses for F-in CH3CN.1H NMR titration showed that the interaction between receptors and anion was mainly based on(C—H)?…X-type ionized hydrogen bonds,and the execess F-promoted the deprotonation of receptors,with the phenomenon of a triplet in 16 ppm which had been proved to be HF2-.3.Design and synthesis of ferrocen-based receptors containing two kinds of recognition sites of imidazolium and Lewis phenylboronic aicd.The recognition of fluoride ion had been studied by using electrochemistry and UV-vis,the results had been showed the receptors containing Lewis phenyl-boronic acid had significant responses to F-.With the addition of fluorid ion,two pairs of redox peaks of receptors had merging into one,and the UV-vis absorption peak had undergone a significant shift phenomenon.1H NMR and 19F NMR titration showed that the phenylboronic acid and imidazolium salt have synergistic effects on fluoride ion recognition,with the addition of F-,F-promoted the deprotonation of receptors,and there were 19F peaks downshift phenomenon also with some peaks generated in 19F NMR,and the significant shift phenomenon in 11B NMR,which further had been proved the interaction between receptors and F-,and had an important role in fluoride recognition.