TEMPO and Carboxylic Acid Functionalized Imidazolium Salts/Sodium Nitrite: An Efficient, Reusable, Transition Metal-Free Catalytic System for Aerobic Oxidation of Alcohols
作者:Cheng-Xia Miao、Liang-Nian He、Jin-Quan Wang、Jing-Lun Wang
DOI:10.1002/adsc.200900285
日期:2009.9
to >99%, even at ambient conditions. Notably, the catalyst system could preferentially oxidize a primary alcohol to the aldehyde rather than a secondary alcohol to the ketone. Moreover, the reaction rate is greatly enhanced when a proper amount of water is present. And a high turnover number (TON 5000) is achieved in the present transition metal-free aerobic catalytic system. Additionally, the functionalized
一种有效的催化系统,包括2,2,6,6-四甲基哌啶-1-氧基(TEMPO)官能化咪唑鎓盐([Imim-TEMPO] + X - ),羧酸取代的咪唑鎓盐([Imim-COOH] + X −)和亚硝酸钠(NaNO 2)被开发用于即使在环境条件下,脂族,烯丙基,杂环和苄基醇有氧氧化为相应的羰基化合物,具有高达> 99%的优异选择性。值得注意的是,催化剂体系可以优先将伯醇氧化成醛而不是仲醇氧化成酮。此外,当存在适量的水时,反应速率大大提高。在目前的无过渡金属需氧催化系统中,获得了很高的周转率(TON 5000)。此外,官能化的咪唑鎓盐可成功重复使用至少四次。因此,通过使用本任务特定的离子液体代替有毒和易挥发的添加剂,该过程代表了将酒精有氧氧化为羰基化合物的绿色途径,2或HCl),这是无过渡金属的好氧氧化醇所必需的。