Study On Synthesis Of Nitrogen-Based And Hyperbranched Ferrocenyl Compounds, Their Electrochemical Behaviors And Application In Anion Recognition

Anions have play important roles in biology,medicine and environment,and to effectively recognize anions has become a meaningful topic so that designing and synthesizing novel anion receptors which can effectively bind anions are becoming a hot area.Ferrocene has stable electrochemical properties,and can provide stable electrochemical signals that can be detected by electrochemical methods,so that ferrocenyl compounds can be used as good anion receptors. Besides that,it can adjust the anion-binding ability of ferrocenyl compounds through changing the redox state of them.In this paper,we designed and synthesized three kinds involved five novel ferrocenyl compounds,studied in details their electrochemical behaviors and investigated the influences of scan rate,solvent,and electrolyte concentration on the electrochemical behaviors. The anion recognition of these ferrocenyl compounds were also studied by CV,UV-Vis and ¹H NMR.The sensitivity and selectivity to different anions were investigated,and the relationship between the structure of anion receptors and the selectivity to an anion were discussed.The mechanism of the anion receptors binding anions was also investigated.A ferrocenyl anion receptor with multiple binding sites of amide group and quarterized nitrogen were designed and synthesized,and its electrochemical behaviors were studied.It found that in different solvent,the electrochemical behaviors showed much difference.The anion recognition behaviors of ferrocenyl compound were also investigated.It was found that the addition of H₂PO₄^-and HSO₄^- caused the "two-peaks" phenomena,and the H₂PO₄^- caused relatively larger response. However,Br^- caused no apparent response.Compared to the ferrocenyl anion receptor with just single binding site of amide group,the ferrocenyl anion receptor with multiple binding sites showed much better sensitivity and selectivity.UV-Vis and ¹H NMR were also used to investigated the anion recognition of the ferrocenyl compound to found that when binding H₂PO₄^-, it was through the step-to-step binding mode of from 1:1 to 1:2,and when binding HSO₄^-,it just through 1:1 binding mode.The dynamics of electrode of the ferrocenyl compound before and after the binding of anions were investigated,and it was found that after binding the anions,the dynamics parameters changed a lot.A kind of ferrocenyl modified hyperbranched polyethers was synthesized,and their electrochemical behaviors in solutions were investigated.The influence of ferrocene content,scan rate,solvent,electrolyte concentration on the electrochemical behaviors were also discussed.The electrode dynamics in different conditions were studied,and the dynamic parameters were calculated.The film electrochemical behaviors in water,methanol,ethanol,isopropanol,n-butanol were also studied,and it was found that the peak current and quantity of electricity increased according to the swelling capacity of the solvents.The anion recognition in CH₂Cl₂ were investigated,and it was found that the peak current decreased with the addition of anions,and H₂PO₄^- caused the fastest decrease rate.The results of UV-Vis indicated that the hyperbranched polyether with smaller ferrocene content bound anions with 1:1 mode.However the hyperbranched polyether with larger ferrocene content bound anions with 2:1 mode when anion amount was small,and with 1:1 mode when anion amount reached higher.A novel water soluble ferrocenyl cycloamine compound was synthesized,and its electrochemical behaviors in organic solvents and aqueous solution were studied.The influence of solvent,scan rate,electrolyte concentration,redox center concentration and acidity on electrochemical behaviors were discussed.The electrode dynamics were studied,and the dynamic parameter were calculated.The anion recognition in CHCl₃ and water was investigated.It was found that with the addition of H₂PO₄^- and HSO₄^-,the redox peak shifted to the lower potential,and HSO₄^- caused larger shifts in CHCl₃.In water,the responses anion caused were much smaller than in CHCl₃ and H₂PO₄^- caused larger response than HSO₄^-.¹H NMR was used to investigated the anion recognition in CHCl₃ and water,and it was found that the addition of H₂PO₄^-,HSO₄^- and F^- made the disappearance of the amine peak,and the shift of ferrocene peak,of which HSO₄^- caused is much larger than H₂PO₄^-.The addition of HSO₄^- also lead to the separation of the peak of the proton directly connected to the amine group.In water,all proton peaks of the ferrocenyl cycloamine compound shifted to the low field,and the shift value was according to the order of H₂PO₄^-＞HSO₄^-＞F^-,which were in accordance with the CV results.