Synthesis And Spectroelectrochemical Properties Of Diferrocenyl Conjugated Moleculars

Electron transfer is very common in physical,chemical,and biological systems,and the mixed valence compound as the simplest model has been widely used to test electron transfer.Recently,termini diferrocene substituted building blocks attached to a heterocyclic core including nitrogen have gained topical interest,due to their conceivable application as model compounds in the study of electron transfer in the mixed-valent species.Cyclic voltammetry was often used to study the intramolecular electron transfer process.Spectroelectrochemical method,which combine spectroscopy with electrochemistry,can provide the spectral information of the oxidation state and the reduced state of the compounds.So spectroelectrochemistry can be more intuitiver to observe the electron transfer process of the compounds.In this thesis,two ferrocene as electrochemical signal groups were introduced into carbazole and pyrazole in order to design ten new nitrogen heterocyclic bridged diferrocenyl derivatives.The electron-transfer characteristics of termini diferrocene-based compounds were studied through spectroelectrochemical method.The main research contents are as follows:1.Four kinds of novel termini ferrocene-based carbazole derivatives(2-9-2-12)have been designed and structurally characterized by IR,MS,1H NMR,13C NMR and HRMS.The electrochemical and spectroelectrochemical(UV-vis-near-IR spectroscopy)properties of these species were studied.These organometallic compounds display two well-resolved electrochemically reversible one-electron-transfer processes.Spectroelectrochemical studies that 2-9-2-12 all belong to the class ? of the mixed valence compounds,its IVCT strength ordering is 2-9+<2-11+<2-10+.The results show that the introduction of methyl or phenyl into the nitrogen atom of carbazole ring will enhance the interaction between two ferrocene of the target molecules.It is worth noting that 2-12 is not found IVCT process in any oxidation state.This may be because that the introduction of acetylene group into between the carbazole ring and ferrocene mocitey will greatly weaken the interaction between the two ferrocene of the target molecule.2.A series of novel termini ferrocene-based pyrazole(3-4-3-9)have been prepared and characterizeed using NMR,IR,and UV-vis spectroscopy.The electronic properties of these compounds were investigated using cyclic voltammetry and spectroelectrochemical.These organometallic compounds display two electrochemically reversible one-electrontransfer processes.Spectroelectrochemical studies that 3-4-3-9 all belong to the class III of the mixed valence compounds,its IVCT strength ordering is 3-6+<3-5+<3-4+<3-9+<3-8+<3-7+.Results show that introducing electron withdrawing group like F atom into pyrazole will enhance the interaction of the two ferrocene between the target molecule.Introducing electron donating groups like methoxy into pyrazole will weaken the interaction of the two ferrocene between the target molecule.