含銅蛋白質活性中心之擬態化合物研究— 含氮硫三牙基之一價錯合物之合成、結構及反應性探討

Synthesis, Structure, and Reactivity of Tridentate N/S Ligand of Copper(I) Complexes—Mimics for the Active Site of Copper Containing Proteins

陳稚愷(Jhin-Kai Chen)

指導教授 ： 李位仁

國立臺灣師範大學/理學院/化學系/碩士(2008年)

摘要

為了模擬藍銅蛋白以及胜肽甘胺酸-羥化氧化酶(Peptidylglycine -hydroxylating monooxygenase，簡稱PHM)的活性中心，我們合成出兩個含氮硫之三牙配位基(BMIMS)與(MITMB)，並成功地合成出兩個具有BMIMS與MITMB的一價銅錯合物：[Cu2(BMIMS)2](CF3SO3)2 (1)和[Cu2(MITMB)2](CF3SO3)2 (4)。將錯合物1與硫醇鹽[SC6H4COO]2-、[SC6F5]-以及[SC6H4Si(CH3)3]-反應，其產物由核磁共振氫譜推測，有[Cu(BMIMS)SC6H4COO-]、[Cu(BMIMS)SC6F5]以及[Cu(BMIMS)SC6H4Si(CH3)3]的生成。將雙核結構的錯合物1和錯合物4與PPh3、CNC(CH3)3、CO等小分子反應則可形成一系列的單核錯合物：[Cu(BMIMS)PPh3](CF3SO3) (2)、[Cu(BMIMS)CNC(CH3)3](CF3SO3) (3)以及[Cu(MITMB)PPh3](CF3SO3) (5)，而[Cu(BMIMS)(CO)](CF3SO3)與[Cu(MITMB)(CO)](CF3SO3)分子的生成由IR光譜鑑定，顯示錯合物1與4都具有良好的反應性。並且藉由核磁共振光譜與IR光譜，得知配子BMIMS的供給電子能力是略強於MITMB。若將氧氣與錯合物1在甲醇/乙腈溶液下反應，以紫外-可見光光譜偵測該溶液可發現在兩組電荷轉移吸收峰在304 nm 、352 nm類似於Cu(II)-OOH錯合物的吸收光譜。

關鍵字

含銅蛋白 ； 擬態化合物

並列摘要

In order to mimic the active site of blue copper protein and peptidylglycine hydroxylating monooxygenase (PHM), we have synthesized two N2S(thioether) ligands, bis(4-methylimidazol-5-yl- methyl) sulfide (BMIMS) and 2-(4-Methylimidazol-5-ylmethyl)- thiomethyl-1-methylbenzoimidazole (MITMB). Two Cu(I) complexes of BMIMS and MITMB, [Cu2(BMIMS)2](OTf)2 (1) and [Cu2(MITMB)2]- (OTf)2 (4) have been successfully synthesized and fully characterized. We aimed to model the active site of the reduced form of blue copper protein by reacting complex 1 with thiosalicylic acid, pentafluoro- thiophenol and 2-(trimethylsilyl)benzenethiol, respectively. 1H-NMR spectra of the isolate products suggested the formation of [Cu(BMIMS)- SC6H4COO-], [Cu(BMIMS)SC6F5] and [Cu(BMIMS)SC6H4Si(CH3)3]. The dinuclear complexes 1 and 4 exhibit excellent reactivities toward small molecules, such as PPh3, CNC(CH3)3, and CO. Mononuclear Cu(I) complexes, [Cu(BMIMS)PPh3](OTf) (2), [Cu(BMIMS)CNC(CH3)3](OTf) (3) and [Cu(MITMB)PPh3](OTf) (5), were formed and structurally characterized, and [Cu(BMIMS)(CO)](OTf), [Cu(MITMB)(CO)](OTf) were characterized by IR. NMR and IR spectra illustrate that BMIMS is a stronger electron-donating ligand compared to MITMB. The reaction of dioxygen with complex 1 in a methanol/acetonitrile mixed solution monitored by UV-vis spectroscopy exhibited two charge transfer absorption bands at 304 nm and 352 nm . The UV-vis spectrum of the resulting species is similar to that of copper(II) hydroperoxide complexes.

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