Synthesis And Electrochemical Properties Of Aromaitc Ferrocenyl Osmacycles

Molecular wire is a kind of device which can realize electron transfer at the molecular scale. Molecular wire has the advantages of small size, diversity and low cost, so it has broad application prospects.Aromatic metallacycles compounds can be regarded as the result of the replacement of one CH group in the traditional aromatic compounds, by a transition metal and its ligands. The central metal d electrons involved in the formation of aromatic ringπ system, electrons can be delocalized over the whole conjugated system. These complexes are potentially useful in the molecular wire.This thesis mainly contains four chapters:In the first chapter, the research background of aromatic metallacycles and molecular wires were introduced.In the second chapter, the new aromatic metallacycles compounds containing osmafuran gme-1 and gme-2 were synthesized, and the formation mechanism of compound gme-1 is proposed. HRMS and NMR were obtained for these new complexes, the compounds of gme-1 was further confirmed by X-ray single crystal diffraction. The redox properties of the gme-1 and gme-2 have been investigated by cyclic voltammetry and square-wave voltammetry. The experimental results show that the less positive redox wave (E1) is ascribed to the Os(Ⅱ)/Os(Ⅲ) couple, The more positive redox process (E1) is proposed to arise from the Fc/Fc+ couple. Due to the effect of CO ligand, the osmium could be more difficult oxidized, the redox potential of Os and Fe is very close; the ligand PPh3 is replaced PMe3, the redox potential of Os becomes more negative.In the third chapter, the aromatic metallapentalyne compounds with ferrocenyl gme-3, gme-4 and gme-5 were synthesized. HRMS and NMR were obtained for these new complexes, The redox properties of the gme-3, gme-4 and gme-5 have been investigated by cyclic voltammetry and square-wave voltammetry. The experimental results show that the redox potential of osmium increased in the presence of CO group in the metallacycle and is closed to the redox potential of Fe in the ferrocenyl. In complex of gme-5, the less positive redox wave (E1) is ascribed to the Fc/Fc+ couple in the ferrocenyl amine group.In the fourth chapter, the main research results was summarized, and the future research work is prospected.