多功能鈀、鎳及銅金屬錯合物的合成與鑑定

Synthesis and Characterizations of Multifunctional Palladium, Nickel, and Copper Complexes

黃凱彥(Kai-Yen Huang)

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/NTU202100184

摘要

若能成功開發出合適的催化劑將小分子轉變為有價值的產品，將有望對於能源貯存跟永續的議題上作出貢獻。在開發的途中所面臨的困難除了較高的活化能外還有轉移電子跟質子的能力，為了解決轉移電子與質子的問題，在設計催化劑時融入了金屬-配位基協同作用(metal-ligand cooperation)及金屬-金屬協同作用(metal-metal cooperation)。這兩種協同作用有望在催化循環中穩定金屬不常見的氧化態及促進電子及質子的轉移。在本論文中，選用pyrazolate作為錯合物橋接配位基來連接雙金屬，並以phenylhydrazone作為配位基側臂來進行金屬-配位基協同作用。
先完成配位基的合成與鑑定後，將配位基分別與三種金屬鹽[PdCl2，NiCl2(dme)2，Cu(PF6)(MeCN)4]反應，分別合成金屬錯合物4、5、6。核磁共振光譜法與X光繞射晶體用來研究三種錯合物在固體與溶液中的結構。循環伏安法則用來探討鈀錯合物4及鎳錯合物5的氧化還原性質。藉由與配位基的氧化峰作對比及理論計算的支持，鈀錯合物4及鎳錯合物5在循環伏安法上的氧化峰皆被認為是配位基為主的氧化反應。在電化學研究上，此二錯合物展現在催化反應中能幫助多電子轉移的可能性，結合配位基上的質子接受者/提供者(pendant proton relay)所提供的多質子轉移的能力，此二錯合物在活化小分子方面具有催化的潛能。

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

It holds promising for energy storage and sustainability issues to develop suitable catalysts for transforming small molecules into value-added commodities. However, the encountered difficulties are not only high activation barriers but the ability to conduct proton transfer and electron transfer. To solve the problem of electron transfer and proton transfer, both metal-ligand cooperation and metal-metal cooperation are introduced in catalyst design. The synergetic cooperation has the potential to stabilize the uncommon oxidation state of metal in the catalyst and facilitate proton and electron transfer in the catalytic cycle. In the thesis, a pyrazolate was chosen to be bridging ligand to bimetallic complex, and phenylhydrazones served as sidearms to perform metal-ligand cooperation.
The synthesis and characterization of the ligand were done firstly, and then the following metalations were done by reacting the ligand with three kinds of metal salts, PdCl2, NiCl2(dme)2, and Cu(PF6)(MeCN)4. NMR spectra and X-ray crystallography were used to study the structure in solid state and solution state of palladium complex 4, nickel complex 5, and copper complex 6. Cyclic voltammetry was used to study the redox properties of complex 4 and complex 5. The oxidation peaks of these two complexes were assigned to be ligand-based oxidation by comparing with the oxidation peak of the ligand and theoretical calculations. The electrochemical studies on complex 4 and complex 5 show the opportunity to conduct multi-electron transfer in catalysis. And the pendant proton relays in the complexes may help multi-proton transfer in catalysis. Thus, these complexes have the potential to catalyze the activation of small molecules.

並列關鍵字

metal-ligand cooperation ； metal-metal cooperation ； multifunctional metallic complex

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