多功能鈷金屬錯合物之合成及應用

Synthesis and Applications of Multifunctional Cobalt Complexes

賴欣妤(Hsin-Yu Lai)

指導教授 ： 張慕傑

國立臺灣大學/理學院/化學研究所/碩士(2021年)

https://doi.org/10.6342/NTU202101891

摘要

近年來致力於減少依賴石化燃料作為主要的能源來源，科學家們積極尋找可替代的燃料。其中，氫氣是廣為人知的能量儲存系統，且由於水是反應完後唯一可能產生的副產物，相對於其他燃料而言對環境的危害較小，常見的研究為利用質子還原反應產生氫氣，若要加速反應的進行，則催化劑的設計勢必為重要的一環。

本篇欲將金屬金屬協同作用(Metal-Metal cooperation)以及金屬配基協同作用(Metal-Ligand cooperation)兩種概念結合於單一錯合物中，因此以1,4-Phthalazine為中心骨架，以diphenylphosphine作為側臂，設計出具有pendent proton relay的螯合配基。在隔絕水氧的反應條件下與所設計之配位基進行反應，合成雙金屬鈷錯合物。藉由X-光繞射、元素分析、電子順磁共振光譜以及循環伏安法等分析儀器，確認錯合物之合成以及其結構特性之鑑定。

將合成之鈷錯合物進行質子還原之電化學實驗，由結果可發現本篇之催化劑在此反應中具有活性。而其中一雙鈷錯合物進行氧化反應後得到的結果，我們初步判定此錯合物可能具有活化水分子的潛能，而得到的另一雙銀錯合物亦值得進行後續的鑑定及應用，這也將成為日後能發展的應用方向。

關鍵字

金屬-配位基協同作用 ； 金屬-金屬協同作用 ； 多功能配位基 ； 多功能金屬錯合物

並列摘要

In recent years, societal resilience toward reducing the dependence on fossil fuel as an energy source make scientists find alternative fuels. Hydrogen is a well-known energy storage system, since that water is the only by-product that may be produced after the reaction, it is less harmful to the environment than other fuels. Common research is to use proton reduction reactions to produce hydrogen. If one wanted to enhance the reaction rate, the design of a catalyst is bound to be an essential part.
A common strategy used in a catalyst design is to combine Metal-Metal and Metal-Ligand cooperation in a single complex. A catalyst might show potential to stabilize uncommon oxidation of metal through synergistic cooperation, and protons and electron transfer could be facilitated. In this thesis, a pendant proton relay containing pincer ligand was designed using the 1,4-Phthalazine as the backbone and diphenylphosphine as a sidearm.
After synthesizing the ligand, metalations under inert reaction conditions were done by reacting with different cobalt salts. Mono-metallic (3) and bimetallic cobalt complexes 4 and 5 can be synthesized. According to X-ray crystallography, cyclic voltammetry, electron paramagnetic resonance and elemental analysis, several analysis methods could confirm cobalt complexes’ properties.
According to a reduction peak appears in complex 4 and 5 cyclic voltammograms. Complex 3, 4 and 5 were served as a catalyst to catalyze an electrochemical proton reduction, all three complexes resulting in a reactive result. Also, according to the result, which shows in an oxidative reaction of one of the bimetallic complexes, we can preliminarily speculate that a cobalt complex shows potential in activating water. A di-silver complex that could also be obtained in the oxidative reaction would be worthy of further studies. Thus, these results might be a route to further development in the future.

並列關鍵字

Metal-Ligand cooperation ； Metal-Metal cooperation ； pendent proton relay

參考文獻

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