(1) Photophysical Properties of Re(diimine)(CO)3Im (2) Photoinduced Oxygen Atom Transfter

• Main Authors: Lin Jen-Chieh, 林人傑
• Other Authors: Chang I-Jy
• Format: Others
• Language: zh-TW
• Published: 2001
• Online Access: http://ndltd.ncl.edu.tw/handle/42301050355270539575

博士 === 國立臺灣師範大學 === 化學研究所 === 90 === Abstract Five Re(LL)(CO)3(Im)+ complexes have been prepared, where LL are 2,2’-bipyridine (bpy), 1,10-phenanthroline (phen), 4,4’-dicarboxyl- 2,2’-bipyridine (bpy(COOH)2), 4’-methyl-2,2’-bipyridine-4-carboxylic acid (mbpy(COOH) and bathophenanthroline disulfonic acid (phen(phSO3H)2). All complexes exhibit metal-to-ligand charge-transfer (MLCT) absorption in the 350 - 380 nm range. Exciting the MLCT transition results in orange luminescence. The 3MLCT emission maxima for these complex range from 580 - 625 nm in aqueous solution. These complexes have higher emission quantum yield and longer lifetime in organic solvent than in aqueous solution. Acetyl microperoxidase-8 (AcMP8, hydrolysis product of cytochrome c) resembles the heme environment of peroxidase on both structure and activities. Photoinduced oxidation of the FeIII to ferryl (FeIV=O) has been observed for AcMP8 in pH=8 buffer solution. In organic-aqueous mixed solvent system, catalytic oxygenation of stilbene by AcMP8 is observed. The system involves a sensitizer (i.e. Ru(bpy)32+), an electron acceptor (e.g. benzoquinone), a catalyst (i.e. AcMP8), and stilbene. Benzaldehyde is the major product. Singlet C60 is generated from photoexcitation and decays to triplet C60 via intersystem crossing. Triplet C60 readily transfers its energy to molecule oxygen and produces singlet oxygen. Singlet oxygen is a powerful oxygen donor, and therefore, reacts with dimethyl sulfide to give dimethyl sulfoxide. Yield of photoproduct and sensitizer stability are highly dependent on the solvent composition. C60 is most stable in a solution of 3 to 1 toluene/methanol mixture. With the presence of a protic solvent (e.g. methanol, water), the oxygenated reaction rate of dimethyl sulfide is faster.