Oligoethylene Glycols as Highly Efficient Mutifunctional Promoters for Nucleophilic-Substitution Reactions
作者:Vinod H. Jadhav、Seung Ho Jang、Hwan-Jeong Jeong、Seok Tae Lim、Myung-Hee Sohn、Ju-Young Kim、Sungyul Lee、Ji Woong Lee、Choong Eui Song、Dong Wook Kim
DOI:10.1002/chem.201102455
日期:2012.3.26
other nucleophiles examined, a fluorine nucleophile generated from CsF was significantly activated by the pentaEG promoter. We also performed various facile nucleophilic‐displacement reactions, such as the halogenation, acetoxylation, thioacetoxylation, nitrilation, and azidation of various substrates with potassium halides, acetate, thioacetate, cyanide, and sodium azide, respectively, in the presence
在此,我们报告了n低聚乙二醇(oligoEGs)作为使用碱金属盐进行亲核取代反应的多官能促进剂。在测试的各种oligoEG中,五甘醇(pentaEG)具有最有效的催化活性。特别地,当与所检查的其他亲核试剂相比时,由pentaEG启动子显着活化由CsF产生的氟亲核试剂。在pentaEG启动子存在的情况下,我们还进行了各种简便的亲核取代反应,例如卤化钾,乙酸盐,硫代乙酸盐,氰化物和叠氮化钠分别对各种底物进行卤化,乙酰氧基化,硫代乙酰氧基化,硝化和叠氮化。所有这些反应以优异的产率提供了它们所需的产物。此外,pentaEG和tert的组合酒精介质在碱性敏感底物与碱性亲核试剂(分别为氟化铯和甲醇钾)的亲核取代反应(氟化和甲氧基化)中显示出巨大的效率。oligoEGs的催化作用已通过量子化学方法进行了研究。发现oligoEGs中的氧原子充当金属阳离子上的Lewis碱,以产生“柔性”亲核试剂,而两个末端