Structural Simulation By Chemical Method And Characterizations Of Active Site Of Enzyme (Hydrogenase)

With high combustion and friendly to the environment,hydrogen is an important and new-type energy source.And it contributes to relieve the energy requirments and greenhouse effect in some degree,which draws the public attentions.Bio-enzyme,especially the[FeFe]-hydrogenase,produces hydrogen efficiently in the mild condition,and is 50-100 times than the[NiFe]-hydrogenase and Fe hydrogenase activity,about 6000-9000 smol-1.There are a number of research findings about the hydrogenase simulation in recent years,but it has high overpotential and poor chemical stability.Some[FeFe]-hydrogenase based on the rigid ligands grows fast recently because of the lower overpotential and better chemical stability than the flexible ligands mimics.It discusses about the[FeFe]-hydrogenase minics based on the rigid ligands in the second chapter in this thesis.Moreover,combining the catalyst with photosensitizer photolysis to produce H2 is energy saving and environmental protection and become a hot research object.Thus,syntheses and characterizations of the[FeFe]-hydrogenase mimics and the self-assembly by the pyridine ring axial to ZnTPP coordination are the main contents of third chapter.The work of this paper is divided into two parts:(1)According to the active center of[FeFe]-hydrogenase,we have prepared a series of electron-donating and electron-withdrawing substituents mimics 1-5 which based on the rigid dithiolate naphthalene ring.The different electron-donating and electron-withdrawing substituents cause effects on the catalytic activity and active center electronic density.Compare the differences in electrochemical behavior of the different proton acids and speculate their possible mechanisms.In addition,the compounds were measured by IR,UV/Vis,NMR,elemental analysis,and their structures were characterized by the crystal diffraction instrument.(2)Syntheses of self-reassembled supramolecular mimic complexes 7?9,7 is by adjusting the rigid naphthalene ring ligand through the pyridine group axial coordination to the ZnTPP;9 is to use the phosphorus ligand to replace the carbonyl group through the pyridine group in the axial direction to the ZnTPP.Compound 9 fluorescence quenching rate is higher than compound 7.Compare the difference in the electrochemical behavior of the different proton acids and speculate their possible mechanism of precursors.Their fluorescence properties were measured by fluorescence spectrometer.In addition,the compounds were measured by IR,UV/Vis,NMR,elemental analysis and single crystal X-ray diffraction.