透過您的圖書館登入
IP:3.236.55.137
  • 學位論文

酚-腙基配位子與其錯合物研究

Studies of Catechol-Hydrazone Ligands and Their Metal Complexes

指導教授 : 王文竹

摘要


本論文合成一系列含酚-腙基的多吡啶配位子,與[RuII(bp)2Cl2]反應後,可得錯合物1、2 及3 (1 = [RuII(bp)2(hzbp-m-cat)](PF6)2、2 = [RuII(bp)2(hzbp-o-cat)](PF6)2、3 = [RuII(bp)2(hzbp-p-OH)] (PF6)2),並對其特性進行研究。 經單晶X光繞射儀鑑定,配位子L2 (L2 = hzbp-o-cat)與L3 (L3 = hzbp-p-OH)均為平面分子,利用分子間氫鍵與π-π作用力支撐,以形成晶體結構。其中,L2具有兩組分子內氫鍵,分別為O-H…N 1.733 (46) Å與O-H…O 2.267 (44) Å。L3的酚與聯吡啶在晶體堆積中相互交疊,顯示配位子有良好的施體與受體,而利於電子傳遞。在三種釕錯合物的單晶結構中,釕與聯吡啶的氮原子形成六配位八面體形狀,兒茶酚或酚未參與配位;此外,聯吡啶與配位子之間具有NH…N分子間氫鍵。釕錯合物的電子吸收光譜中,有配位子、聯吡啶的π-π*電子躍遷及MLCT吸收峰。發射光譜中,600 nm有一放射峰,此為3MLCT磷光。電化學的氧化掃描,錯合物1及2均有一組可逆的釕(II/III)氧化還原峰,另有兒茶酚至半醌及半醌至醌的氧化峰;錯合物3除了可逆的釕(II/III)氧化還原峰外,亦有酚的逐步氧化峰。還原掃描中,錯合物1、2 及3有非配位子的聯吡啶各一個電子可逆氧化還原峰,而後為配位子不可逆或準可逆的還原峰。 此系列釕錯合物對氟離子具優異辨識性,用肉眼即可辨識顏色變化。錯合物1的氟離子滴定實驗發現,除了電子吸收光譜中MLCT吸收峰有顯著的變化外,於750 nm會生成一個寬廣吸收峰,半衰期估算為46秒。經ESR光譜印證,確認為有機自由基,錯合物2與錯合物3並無此現象產生。錯合物的酸鹼滴定實驗發現,[OH-]與氟離子的作用相似,顯示溶液顏色的變化,來自錯合物的去質子化。藉由核磁共振光譜的探討得知,加入氟離子後,釕錯合物的兒茶酚或酚基首先被去質子化。加入氟離子或提高pH值,可使錯合物的兒茶酚或酚轉變為半醌或醌,使整體電子組態改變,引發顏色變化,達到偵測氟離子的效果。

並列摘要


A series of new ruthenium(II) complexes, 1 = [RuII(bp)2(hzbp-m-cat)](PF6)2, 2 = [RuII(bp)2(hzbp-o-cat)](PF6)2 and 3 = [RuII(bp)2(hzbp-p-OH)] (PF6)2, were synthesized. The structures were confirmed by single crystal X-ray diffraction study. Characteristics of these compounds were investigated by EA, 1-D & COSY NMR, ESI-mass, UV-vis, phosphorescence, electrochemistry, and ESR spectra. In the absorption, emission, and 1H NMR titration spectra studies revealed that these complexes can be employed as a sensor for fluoride. A distinguishable deep color change in acetonitrile solution was observed. These phenomena were also appeared upon pH value changed. Furthermore, a broad band was appeared at 750 nm in UV-vis titration spectra which revealed the free radical generated from complex 1. The existence of free radical was confirmed by ESR spectra. The HOMO, LUMO of ruthenium complexes and relative binding affinity of fluoride anion toward ligands were evaluated and rationalized with quantum chemical calculations. Finally, we proposed sensing fluoride and deprotonation mechanism to explain the experiments in detail. The protons at catechol or phenol can be removed by additional fluoride or hydroxide.

並列關鍵字

Ruthenium fluoride sensor semiquinone radical phenol bipyridine

參考文獻


63. Stewart, J. J. P. MOPAC, version 6.0; Frank J. Seiler Research Laboratory: Air Force Academy, CO, 1990.
7. (a) Gräetzel, M. J. Photochem. Photobiol., C: Chem. 2003, 4, 145-153. (b) Nazeeruddin, M. K.; Zakeeruddin, S. M.; Lagref, J. J.; Liska, P.; Comte, P.; Barolo, C.; Viscardi, G.; Schenk, K.; Gräetzel, M. Coord. Chem. Rev. 2004, 248, 1317-1328.
103. (a) Tzeng, B. C.; Chen, Y. F.; Wu, C. C.; Hu, C. C.; Chang, Y. T.; Chen, C. K. New J. Chem. 2007, 31, 202-209. (b) Wu, C. Y.; Chen, M. S.; Lin, C. A.; Lin, S. C.; Sun, S. S. Chem. Eur. J. 2006, 12, 2263-2269.
61. (a) Su, C. H.; Chang, I. J. J. Chin. Chem. Soc. 1998, 45, 361-365. (b) Su, C. H. Photophysical Properties Of Ruthenium(II) Polypyridyl Complexes. Ph.D. Thesis, National Taiwan Normal University, May 2000.
54. (a) Cui, Y.; Niu, Y. L.; Cao, M. L.; Wang, K.; Mo, H. J.; Zhong, Y. R.; Ye, B. H. Inorg. Chem. 2008, 47, 5616-5624. (b) Cui, Y.; Mo, H. J.; Chen, J. C.; Niu, Y. L.; Zhong, Y. R.; Zheng, K. C.; Ye, B. H. Inorg. Chem. 2007, 46, 6427-6436.

延伸閱讀