Pd(II)金屬催化下8-methylquinoline的氟化反應之理論探討

機構典藏 > College of Sciences > Graduate Institute & Department of Chemistry > Thesis > Item 987654321/93972

Please use this identifier to cite or link to this item: https://tkuir.lib.tku.edu.tw/dspace/handle/987654321/93972

Title:	Pd(II)金屬催化下8-methylquinoline的氟化反應之理論探討
Other Titles:	Pd(II)-catalyzed fluorination of 8-methylquinoline : a DFT study
Authors:	王子豪;Wang, Tzu-Hao
Contributors:	淡江大學化學學系碩士班王伯昌;Wang, Bo-Cheng
Keywords:	催化;模擬;氟化反應;DFT;Pd(OAc)2;B3LYP;fluorination
Date:	2013
Issue Date:	2014-01-23 13:44:52 (UTC+8)
Abstract:	本論文主要為探討以Pd(II)進行金屬催化8-methylquinoline的氟化反應之理論計算研究，所模擬的反應參考一篇的實驗論文，將其路徑分為三階段，每一個階段皆有結構變化、能量圖與NBO圖電荷分析，計算方法選擇為DFT的計算函數b3lyp，搭配基底函數lanl2dz。第一階段進行Pd(OAc)2的氧化加成(Oxidative addition)反應，其中包含碳-氫鍵活化(C-H activation)反應，本論文計算模擬得知兩種可能路徑，考慮其金屬配位因素，選擇合理的路徑做後續的模擬與分析。第二階段實驗中氟化劑內含氟原子電性偏F+性質，這是一種較少見的方式，由於氟的陰電性極高，要帶正電性是極為不容易的，本論文的模擬結果顯示，氟一旦脫離氟化劑，會快速抓取附近原子上的負電恢復其電性，在此種類似正電性質下，氟能夠較易的脫離氟化劑，以利進行此階段之反應，此外模擬後發現氟化劑之性質顯著影響反應的難易。第三階段為還原脫去(reduction eliminative)反應，氟透過還原脫去反應轉移至碳，最後與Pd鍵結之兩個OAc，重新配位生成Pd(OAc)2，而脫去反應物，完成整個反應的模擬。本論文計算之結果得知第二階段氟化劑，使F帶類似正電性質，此為整個反應能否進行的關鍵，依造以F+為主，設計出的不同氟化劑，將影響此種反應進行的難易，根據其結果，能提供實驗設計上更多更好的想法。 This thesis is focus on the reaction mechanism of palladium-catalyzed fluorination of 8-methylquinoline. In order to figure out the mechanism and restrictions of the fluorination reaction, we refer a published experimental paper, which divided the pathway into three steps. Each step will have the structural analysis, the NBO analysis and the energy diagram analysis. Besides, geometry optimization was carried out with the DFT method by using B3LYP functional and lanl2dz In step 1, we have the Oxidative addition reaction by Pd(OAc)2 which also include C-H activation reaction. We predict two possible pathways by using molecular stimulation calculation. However, there is one pathway has ligand problem so we choose anther reasonable pathway to continue step 1 simulation. In the step 2, the experiment uses the electrophilic fluorinating reagent (F+) to join our reaction. Since fluoride is highly electronegative so it is not easy to make it electrophilic. In our study, we found out that F+ of the fluorination reagent could leave the reagent easily in order to finish the reaction. Besides, the property of fluorinating reagent will affect the reaction difficulty. In the step 3, we have the reduction eliminative reaction. Under this reaction, fluoride can be transferred to the target carbon forming C-F bond. Finally, two OAc bonds of Pd will rearrange to Pd(OAc)2, which can leave the reactant and finish the full simulation pathway. In conclusion, the fluorinating reagent is the key factor of this reaction. Therefore, developing different kinds of fluorinating reagent can provide more efficient and better fluorination reaction.
Appears in Collections:	[Graduate Institute & Department of Chemistry] Thesis

Files in This Item:

File	Size	Format
index.html	0Kb	HTML	218	View/Open

Loading...