請用此 Handle URI 來引用此文件:
http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/29555
標題: | 弱配位金屬鹽類[M(上標 n+)(BAr(上標 F)4)(上標-)(下標 n)]在酸催化的應用 Applications of Weakly Coordinated Metal Salts [M(superscript n+)(Bar(superscript F)4)(superscript -)(subscript n)]in Acid Catalysis |
作者: | Bei-Sih Liao 廖倍偲 |
指導教授: | 劉緒宗 |
關鍵字: | 酸催化,弱配位, Acid Catalysis,Weakly Coordinated, |
出版年 : | 2007 |
學位: | 碩士 |
摘要: | 摘 要
M(上標 n+)(BAr(上標 F)4)(上標-)(下標 n) [M = 鋰、鈉、鉀、銫、鎂、鈣、銀、鎳、鋅,ArF= 3,5-(trifluoromethyl)bromobenzene ] 在水溶液中,能進行酸催化的反應。金屬離子除了具有路易士酸的特性外,在陰離子的協助下,經由與水配位後,也能產生氫離子(H+),扮演布羅斯特酸的角色。 因此,M(上標 n+)(BAr(上標 F)4)(上標-)(下標 n)利用酸的性質可以催化聚合、水解縮醛、Mannich reaction、Biginelli reaction及合成bsindoles的反應,並得到不錯的效果。而屬於弱配位的陰離子(BAr(上標 F)4)(上標 -),在水溶液中會造成相轉移的現象,利用所形成微胞的系統,可使催化反應能順利的進行,並有效地縮短反應時間與降低反應溫度。 此論文中係利用M(上標 n+)(BAr(上標 F)4)(上標-)(下標 n)在水中進行不同類型的催化反應,不僅克服傳統路易士酸,如AlCl3、TiCl4、BF3.OEt2等,必須在無水狀態下進行催化的缺點,並減少有機溶劑的使用,使其儼然成為新一代的有機金屬催化試劑。 Abstract Metal salts, M(superscript n+)(Bar(superscript F)4)(superscript -)(subscript n) [M = Li、Na、K、Cs、Mg、Ca、Ag、Ni、Zn,ArF= 3,5-(trifluoromethyl)bromobenzene ], were prepared and employed as acid catalysts in aqueous medium. In addition to the Lewis acid property of metal ions, the hydrated metal ions associated with the tetraarylborate act as good Bronsted acid in water. Therefore, using these metal salts in catalyzing various reactions, such as preparation of bisindoles、Mannich reaction、Biginelli reaction、hydrolysis of acetal is investigated. In fact, the anion [(BAr(superscript F)4)(superscript-)] plays an important role in catalysis. In water, metal salts of tetrakis[3,5-di(trifluoromethyl)phenyl]borate and organic substrates would form a colloidal dispersion during the reaction. The emulsion appeared to accelerate the reaction. These metal salts could be as catalysts and surfactants to promote various reaction in a micellar system. Thus condensations or hydrolysis proceeded immediately under high concentration within the micelle. This procedure offers several advantages for the preparation of various organic compounds such as mild conditions, low loading of catalyst, high yields and in aqua medium, which make it a useful and attractive methodology for organic synthesis. |
URI: | http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/29555 |
全文授權: | 有償授權 |
顯示於系所單位: | 化學系 |
文件中的檔案:
檔案 | 大小 | 格式 | |
---|---|---|---|
ntu-96-1.pdf 目前未授權公開取用 | 9.29 MB | Adobe PDF |
系統中的文件,除了特別指名其著作權條款之外,均受到著作權保護,並且保留所有的權利。