應用可再使用的鈀/2,2'-雙吡啶催化系統在水中進行Mizoroki-Heck及共軛加成反應之研究

The applications of reusable palladium/cationic 2,2'-bipyridyl catalytic system for the Mizoroki-Heck reaction and conjugate addition in water

黃紹峴(Shao-Hsien Huang)

指導教授 ： 蔡福裕

國立臺北科技大學/工程學院/工程科技研究所/博士(2011年)

摘要

隨著綠色化學的興起，我們製備了可溶水性的陽離子2, 2’-雙吡啶配位基，分別利用此配位基，將鈀金屬帶到純水中來進行碳碳鍵的生成反應，銠金屬來進行苯乙炔的聚合，及鐵金屬來進行硫醚鍵的生成反應。且我們致力於將二氯二氨鈀/陽離子2, 2’-雙吡啶配位基系統作再使用的動作，希望達成一種高效能且具再使用的催化系統。
我們發現這種二氯二氨鈀/陽離子2, 2’-雙吡啶配位基催化系統在純水中，以三丁胺為鹼，對碘代芳烴和烯類的碳碳鍵生成，具有高效益的催化能力及再使用的功能。在密封可耐高壓的反應瓶內，僅1×10-6 mmol的催化劑量，即可以使碘代芳烴和丙烯酸丁酯及丙烯酸乙酯反應，得到不錯的產率及相當高的 turnover numbers，而在苯乙烯的反應中，在四丁基溴化胺的幫助及較大催化量(1 mol%)下，仍是可以得到較高的產率。且每次反應完後，經由萃取完所殘留下來的水溶液可以進行再使用的動作，活性僅有些微的衰退表現。
這種可再使用的二氯二氨鈀/陽離子2, 2’-雙吡啶配位基催化系統，也可以用來進行有機硼試劑和羰基不飽烯類的共軛加成反應。不論是環合還是非環合的和羰基不飽烯類，皆能有效的和有機硼試劑進行反應，尤其是在加入四氟硼酸將反應的pH值調至1後，更是可以得到相當高的產率。在反應結束後，殘留的水溶液也可以進行再使用數次，減少催化劑浪費。
此二氯二氨鈀/陽離子2, 2’-雙吡啶配位基催化系統，我們發現也可以用來作1, 4-萘醌的arylation反應，它能有效地以催化劑量來進行，並且在不需要含有鹵素的前驅物下即可反應。除此之外，在四氟硼酸的幫助下，反應可以不添加額外的金屬氧化劑來得到產物，且反應後所殘留的水溶液也能有效的進行再使用數次，成功地減少了金屬不必要的浪費。

關鍵字

Mizoroki-Heck反應 ； 可水溶性催化劑 ； 再使用 ； 偶合反應 ； 共軛加成 ； 啶催化系統 ； pH值依賴性

並列摘要

We have recently prepared water-soluble cationic 2, 2’-bipyridyl ligand and utilized it to bring a palladium complex into the aqueous phase for carbon–carbon bond-forming reactions, a rhodium complex for phenylacetylene polymerization, and an iron salt for S-arylation under aerobic conditions. As part of our continuing efforts in the development of green and reusable catalytic systems, we report herein the combination of Pd(NH3)2Cl2 and cationic 2, 2’-bipyridyl ligand to create a highly-efficient and reusable catalyst for carbon–carbon bond-forming reactions.
A water-soluble and air-stable Pd(NH3)2Cl2/cationic 2, 2’-bipyridyl system was found to be a highly-efficient and reusable catalyst for the coupling of aryl iodides and alkenes in neat water using Bu3N as a base. The reaction was conducted at 140 °C in a sealed tube in air with a catalyst loading as low as 0.0001 mol % for the coupling of activated aryl iodides with butyl and ethyl acrylates, providing the corresponding products in good to excellent yields with very high turnover numbers. In the case of styrene, Mizoroki-Heck coupling products were obtained in good to high yields by using a greater catalyst loading (1 mol %) and TBAB as a phase-transfer agent. After extraction, the residual aqueous solution could be reused several times with only a slight decrease in its activity, making the Mizoroki-Heck reaction “greener”.
A reusable Pd(NH3)2Cl2/cationic 2, 2’-bipyridyl system for the catalysis of the conjugate addition of arylboronic acids to α, β-unsaturated enones in water under air was developed. Addition of arylboronic acids to both cyclic and acyclic enones progressed smoothly, providing the products in good to high yields, the best result being obtained when HBF4 was used to adjust the pH value to 1.0. After the reaction, the residual aqueous solution could be reused several times, making the reaction greener and reducing wastage of precious metals.
A mild way to catalyze the arylation of 1, 4-Quinones was developed. It could be carry out under the catalyst amount of metal, and didn’t need halide or persuade halide groups on the initial. In addition, the reaction could be proceeded by using HBF4 to adjust the pH value to 1.0, and didn’t need extra metal as an oxidant to get the product. Moreover, the residual aqueous solution after reaction also could be reused several times to reduce the wastage of metals.

並列關鍵字

Mizoroki-Heck reaction ； water-soluble catalyst ； reusable ； water ； cross-coupling ； pH-dependent ； conjugate addition

參考文獻

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