利用可見光於氧氣中促進苄基溴氧化反應的探討

Visible Light Promoted Aerobic Oxidation of Benzyl Bromides

陳苑菁(Yuan-Ching Chen)

指導教授 ： 莊敬

中原大學/理學院/化學研究所/碩士(2019年)

https://doi.org/10.6840/cycu201900586

摘要

本研究以苄基溴類化合物為起始物，於氧氣下照射可見光(白光LED)進行氧化反應，得到目標的醛類化合物。在完成與本實驗室涂瀞文同學合作之最佳化條件測試後，我們以不同的苄基溴化類化合物來進行官能基容忍度測試，發現本反應有良好的官能基容忍度。同時，為了對本反應機制有所了解，故我們嘗試追蹤其反應過程，並探討影響起始物消耗與產物生成速率之因素。依實驗結果推測本反應中有溴分子或溴離子的生成，可進一步催化產物的生成。另外，我們猜測本反應與Kornblum氧化反應機制相似，因此我們分別探討了本反應與Kornblum氧化反應之動力學同位素效應（KIE）。此外我們也使用了自由基起始劑及自由基抑制劑做檢測，推測反應過程中有自由基中間體的生成。

關鍵字

苄基溴 ； 可見光 ； 氧氣

並列摘要

In this study, benzyl bromides were used as starting materials, and with visible light (white LED) irradiation under oxygen to generate target aldehyde compounds. After completing the optimization test with the Jin-Wen Tu tested the functional group tolerance of the reaction. By monitoring the reaction by HPLC, we found Br2 and Br ion have an accelerating bromine (Br2) effect on the reaction rate. In addition, we conducted kinetic isotope effect (KIE) experiment and found that the kH/kD ratio similar to Kornblum oxidation. We also used free radical initiators and free radical inhibitors for mechanistic study, and the result have shown possible involvement of free radical intermediates in the reaction process.

並列關鍵字

benzylbromide ； visible light ； oxygen

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