叁牙氮配位基金屬錯合物之合成及催化應用

Synthesis and Catalytic Application of Metal Complexes with Tridentate Nitrogen Ligand

李雁婷(Yen-Ting Lee)

指導教授 ： 劉緒宗

國立臺灣大學/理學院/化學研究所/碩士(2010年)

https://doi.org/10.6342/NTU.2010.00676

摘要

有機化合物2,6-bis(pyrazol-1-yl)pyridine (簡稱pp) 與2,6-bis(3,5-dimethyl- pyrazol-1-yl)pyridine (簡稱dmpp)具三個可以與金屬配位氮原子，有強螯合能力。本篇論文探討pp、dmpp與二價鐵、鈷、鎳金屬錯合物的合成，以及其催化反應性質。
藉由2,6-二溴吡啶和吡唑在鹼性環境中反應以合成配位基pp或dmpp，進而分別與氯化亞鐵、氯化亞鈷及氯化鎳作用，即可得到對應的二價金屬錯合物。以質譜、紅外線光譜儀、元素分析來鑑定結構，其中二價鈷錯合物，[Co(pp)(H2O)3]Cl2及[Co(dmpp)Cl2]，可利用乙腈或甲醇做再結晶，藉由X光繞射儀分析，得到結構資訊。
有關催化反應，測試氫轉移還原反應及Ullmann偶合反應均未有極佳的效益。另外， NiCl2˙2(H2O)和pp催化劑可促使一系列醛肟脫水生成腈；然而，NiCl2˙2(H2O)本身具不錯的催化活性，pp的載入無法有效提升反應速率。最後，本論文研究亦發現4-硝基苯醛肟、2-呋喃醛肟或是雙苯醛肟在此反應系統會脫水生成腈，或是異構化成醯胺。

關鍵字

氮配位基 ； 錯合物 ； 催化

並列摘要

2,6-Bis(pyrazol-1-yl)pyridine (pp) and 2,6-bis(3,5-dimethyl- pyrazol-1-yl)pyridine (dmpp) are strong N-donor ligands. In this work, we prepared pp and dmpp, synthesized the corresponding Fe(II), Co(II), and Ni(II) complexes, and focused on their catalytic application.
The ligands, pp and dmpp, could be prepared via nucleophilic coupling of deprotonated pyrazole and 2,6-dibromopyridine. Next, pp or dmpp could react with the metal precursor(MCl2, M = Fe, Co, Ni) to form the complexes. We could characterize the structure of the complexes by Mass Spectrum Analysis, Infrared Spectroscopy, and Element Analysis. Among them, the crystal structure of [Co(pp)(H2O)3]Cl2 and [Co(dmpp)Cl2] could be obtained by X-ray diffraction analysis.
As to catalytic application, using metal precursor with pp or dmpp ligand as catalyst did not show good reaction activity on hydrogen transfer reaction and Ullmann coupling. NiCl2˙2(H2O) and pp catalyst could successfully promote the dehydration of a series of oxime to form nitrile. However, adding pp could not evaluate the reaction rate efficiently. We also found that if 4-nitrobenzaldehyde oxime, 2-furanecarboxaldehyde oxime, or benzaldehyde dioxime were as substrate, the reaction would afford nitrile and amide product under the catalytic system.

並列關鍵字

N-donor ligand ； Complex ； Catlaysis

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