Summary: | 碩士 === 國立臺灣師範大學 === 化學研究所 === 89 === Six rhenium diimine tricarbonyl complexes have been synthesized. Re(dnbpy)(CO)3Cl and Re(mcbpy)(CO)3Cl (where dnbpy = 4,4-dinitro-2,2-bipyidine, mcbpy = 4-methyl-2,2-bipyridine-4-carboxylic acid) were synthesized from direct ligand substitution. In basic solution, Re(dnbpy)(CO)3Cl undergo SN2 substitution reaction to replace -NO2 and give Re((MeO)2bpy)(CO)3(CH3O), Re((EtO)2bpy)(CO)3(C2H5O), Re(imbpy)(CO)3(im)Cl, and Re((im)2bpy)(CO)3(im)Cl complexes(where im = imidazole).
In acetonitrile solution, these complexes have excited-state lifetime of 77, 340, 404, and 6143 ns for Re(mcbpy)(CO)3Cl, Re((MeO)2bpy)(CO)3(CH3O), Re((EtO)2bpy)(CO)3(C2H5O), and Re(imbpy)(CO)3(im)Cl, respectively. Emission quantum yields are 0.025, 0.017, 0.012, 0.0486, and 0.0019 for Re(mcbpy)(CO)3Cl, Re((MeO)2bpy)(CO)3(CH3O), Re((EtO)2bpy)(CO)3(C2H5O), Re(imbpy)(CO)3(im)Cl, and Re((im)2bpy)(CO)3(im)Cl, repectively. The lifetime and quantum yield of the non-substituted bipyridine complex, Re(bpy)(CO)3Cl, are 39 ns and 0.0031, respectively. Complexes prepared in this thesis have much higher quantum yield and longer lifetime and, therefore, are better candidates for photochemistry.
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