1.苯胺衍生物與功能性紫質的電化學性質研究 2.電化學誘導氫鍵的循環伏安法模擬研究

1. Electrochemical Studies of Oligoarylamines and Functional Metalloporphyrins 2. Cyclic Voltammetry Simulation of Electrochemically Induced Hydrogen Bonding

鄭旭均(Hsu-Chun Cheng)

指導教授 ： 蘇玉龍

國立暨南國際大學/科技學院/應用化學系/博士(2014年)

https://doi.org/10.6837/NCNU.2014.00157

摘要

本論文包含兩章，第一章是在探討苯胺衍生物和功能性紫質的合成、電化學與光譜電化學研究，第二章為電化學誘導氫鍵的循環伏安法與模擬研究。
在第一節中，以三苯胺(triphenylamine, TPA)為單體，串連二∼六個三苯胺的直線型苯胺衍生物被合成，而藉由循環伏安法可以觀察到此系列化合物的氧化行為可以分為兩種，分別是一次失去一個電子的氧化和以對苯二胺(phenylenediamines)為單位進行氧化反應，進一步以電子自旋共振光譜儀檢視氧化的性質。此外利用透光薄層電化學法可以觀察其分子內的電子轉移(intramolecular charge transfer, ICT)的性質，並以DFT calculation來佐證EPR的結果。
合成一個含有對苯二胺(phenylenediamine, PD)的鋅紫質，利用電位來控制imidazole(HIm)所配位的位置。當中性狀態下，HIm是鍵結在鋅紫質的中心金屬中，而當電位造成PD部分氧化，氧化後的PD會與HIm形成氫鍵而造成HIm的轉移。同時，我們也將兩個氧化還原中心距離加長，觀察距離對於配位基轉移的影響，進一步探討各個電位下，每個部份的形成常數，我們可以更了解其中HIm轉移的情形。
在循環伏安法中，因為電化學誘導氫鍵的產生，可以穩定某些氧化態下的分子，造成電位上的偏移，本研究是利用三苯胺上的氨取代基(amino group)數量來微調電化學誘導氫鍵的性質(TPA-(NH2)x, x = 1, 2 and 3))，並以循環伏安法模擬來進一步探討更細微的電化學反應的反應機制和各個參數。此外，利用DFT calculation來佐證我們的推論。
最後一節是利用對苯二胺衍的同分異構物(APD1和APD2)滴定imidazole來觀察結構上對於電化學誘導氫鍵的影響，並且利用循環伏安法模擬來進一步探討更細微的電化學反應的反應機制和各個參數。光譜電化學也被嘗試使用來觀察氫鍵的產生，此外，DFT calculation所得到的結果被用來佐證我們的推論。

關鍵字

電化學 ； 光譜電化學 ； 對苯二胺 ； 鋅紫質 ； 電子順磁共振光譜 ； 電化學誘導氫鍵 ； 循環伏安法模擬

並列摘要

The thesis involves two parts.
The first one includes the synthesis, electrochemical and spectral studies of oligoarylamine containing two to six redox centres. Depending on their electrochemical characteristics, these oligoarylamines were classified into two groups: one containing an odd number and the other an even number of redox centers. In the systems with odd redox centers (N1, N3, and N5), each oxidation was associated with the loss of one electron. As for the systems with even redox centers (N2, N4, N6), oxidation occurred by taking N2 as a unit. DFT-computed isotropic hyperfine coupling constants and spin density were in accordance with the EPR experiment, and gave a close examination of oligoarylamines at charge state.
Investigations on the transfer of the ligand, imidazole (HIm), between two covalently linked redox centres–zinc porphyrin and phenylenediamine (PD)–and the influence of the length of the linker are reported. Since the binding affinity of the ligand with zinc porphyrin is different from that of the ligand with the phenylenediamine moiety, the transfer of the ligand could be electrochemically controlled by adjusting the oxidation potentials. Changes in cyclic voltammograms and absorption spectra of the complexes revealed the site of ligand binding in the various oxidation states of the modified zinc porphyrins. Binding constants of the modified zinc porphyrins in various oxidation states were also determined by photometric titration with the ligand and digital simulations. Evidence for the delocalization of the electron from the zinc porphyrin to phenylenediamine moiety and the influence of the delocalization on them were obtained from EPR studies.
In the second part, by increasing the number of amino-substituents on triarylamine(TPA), the extent of hydrogen bonding between the oxidized form of triarylamine and imidazole could be electrochemically controlled. Three behaviors, depending on the interaction between oxidized amine and imidazole, were obtained in CV patterns. DFT calculation was used to confirm that the electron density of protons of the amino group decreased as amino moiety increased.
In oxidative aspect of cyclic voltammogram, the unlike phenylendiamines (APD1 and APD2) had different patterns of electrochemically induced hydrogen-bonding. Especially in APD2, the ratio of titration is less than one euivalent, two resolved waves observed, and one shifted wave formation while the ratio is more than one. The detail electrochemical properties were detected. DFT calculation was used to confirm that the electron density of protons of the amino group.

並列關鍵字

Electrochemisty ； Spectroelectrochemistry ； Phenylenediamine ； Porphyrin ； Electron paramagnetic resonance ； Electrochemically induce hydrogen bonding ； Cyclic Voltammetry simulation

參考文獻

(1)

1. Tang, C. W.; Van Slyke, S. A. Appl. Phys. Lett. 1987, 51, 913.

2. VanSlyke, S. A.; Chen, C. H.; Tang, C. W. Appl. Phys. Lett. 1996, 69,2160.

3. Burrows, P. E.; Sapochak, L. S.; McCarty, D. M.; Forrest, S. R.; Thompson, M. E. Appl. Phys. Lett. 1994, 64(20), 2718.

4. (a) Hua, Y. Y.; Chen, S.; Yang, X.; Hou, Y.; Xu, X. Syn. Met. 2000, 111, 109. (b)Shao, Y.; Qiu, Y.; Hu, X.; Hong, X. Chem. Lett. 2000, 1068.