| Summary: | 碩士 === 國立中央大學 === 化學學系 === 105 === A series of dinuclear rhenium(I) tricarbonyl complexes [Bppb-Re-R] and [BppEb-Re-R] (R = Br, Ph (4-phenylpyridine), L1 (2-hexyl-7-pyridin-4-yl-benzo[lmn][3,8]phenanthroline-1,3,6,8-tetraone) containing bidentate 1,3-bis((3-(pyridine-2-yl)-1H-pyrazol-1-yl)methyl)benzene (Bppb) or 1,2-bis(2-(3- (pyridine-2-yl)-1H-pyrazol-1-yl)ethyl)benzene (BppEb) ligand has been designed and synthesized.
The 1H NMR spectra of Bppb-Re-Ph and Bppb-Re-L1 showed distinct signals, indicative of both Bppb-Re-Ph and Bppb-Re-L1 possessing two conformations. The single crystal of Bppb-Re-Ph for X-ray diffraction with U-shaped conformation was grown by diffusing diethyl ether into an acetone solution. The 1H NMR spectrum of the U-shaped isomer showed the signal at δ = 9.39 ppm. Thus, the signal located at δ = 9.34 ppm may be attributed to the conformation isomer of Z form.
The absorption spectrum of Bppb-Re-Ph with U-shaped conformation exhibited broad absorption between 330 and 390 nm with a predominant character of 1MLCTRe→Bppb transition and the emission spectrum displayed at 500 nm. (quantum yield 0.279, lifetime 2.34 µs in CH2Cl2)
Comparing to those of Bppb series, the 1H NMR spectra show that both BppEb-Re-Ph and BppEb-Re-L1 may have only one conformation.
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