可回收水溶性鈷觸媒催化硫－碳鍵生成反應

A Reusable Cationic 2,2'-Bipyridyl/Cobalt (II) System Catalyzed Sulfur－Carbon Bond Formation Reaction in Water

藍明姿(Ming-Tzu Lan)

指導教授 ： 蔡福裕

國立臺北科技大學/工程學院/有機高分子研究所/碩士(2010年)

摘要

本實驗目的為開發在水中擁有極高溶解度的陽離子配位基，在與過渡金屬-鈷配位形成具有極佳催化活性的金屬觸媒，此觸媒可在水溶液和大氣中進行高效率之有機催化碳異原子鍵的反應。由於碳-硫鍵常出現在生物、藥物以及材料化學方面，所以越來越受到重視；雖然一般像銅、鈀、鎳常用在這種偶合反應，但需要高溫、高催化量或者特別設計的含磷的配位基；再者，有機溶劑通常都具有毒性且易燃，容易造成產物的分離不易。在此，我們希望符合綠色化學的概念，使用環保且便宜的 CoCl2．6H2O 當作催化劑，而溶劑使用最無毒害的水，
　　我們利用此觸媒系統來催化aryl halides (aryl iodides, aryl bromides and aryl chlorides) 與各種不同thiols (aromatic thiols, aliphatic thiols and hetroaromatic thiols) 之偶合反應，大部分反應皆可於溫和之條件下得到高產率。
對於再回收的活性測試方面，也能經由離心步驟除去zinc dust後，進行五次的再回收反應，仍有 80％ 以上的產率，証明我們的水溶性鈷觸媒不但擁有極好的催化活性，也能進行具有經濟效益的再回收反應，這是一般均相反應所無法達到的目標。

關鍵字

鈷金屬錯合物 ； 可回收 ； 硫－碳鍵生成反應 ； 水溶性觸媒

並列摘要

A transition-metal-catalyzed cross-coupling reaction between aryl halides and thiols is an actively investigated field in organometallic chemistry. The aryl-sulfur bonds are prevalent in many molecules used in biological, pharmaceutical and material sciences. Formerly, the syntheses of aryl-sulfur bonds often require harsh conditions. In our study, we wish to develop an inexpensive and environmentally friendly catalytic system to construct S-arylation coupling using CoCl2．6H2O as a catalyst, and water as the sovent. This methodology is applicable to a wide range of aryl thiols derivatives, and aryl iodides, bromides, and chlorides.
After reaction, the zinc dust was centrifuged from the reaction mixture, and the water-soluble catalytic system was separated from the organic products by extraction with hexane. The catalytic system can be reused for at least 5 times with only slight decrease in activity.

並列關鍵字

water-soluble catalyst ； reusable ； C-S bond formation ； cobalt-catalyzed reaction

參考文獻

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