Highly selective trifluoroacetic ester/ketone metathesis: an efficient approach to trifluoromethyl ketones and esters
作者:Yuhan Zhou、Dongmei Yang、Gen Luo、Yilong Zhao、Yi Luo、Na Xue、Jingping Qu
DOI:10.1016/j.tet.2014.05.017
日期:2014.8
atom efficient ‘trifluoroacetic ester/ketone metathesis’ has been sincerely witnessed. Enolizable alkyl (at least two non-hydrogen atoms) aryl ketones were found to react readily with ethyl trifluoroacetate under the promotion of NaH to afford trifluoroacetic ester/ketone exchange products, trifluoromethyl ketones (TFMKs), and aromatic acid esters, which were quite different from the general Claisen
真诚地见证了高度选择性和原子效率的“三氟乙酸酯/酮复分解”。发现可烯化的烷基(至少两个非氢原子)芳基酮在NaH的促进下易于与三氟乙酸乙酯反应,得到三氟乙酸酯/酮交换产物,三氟甲基酮(TFMK)和芳族酸酯,它们是完全不同的由一般的克莱森缩合产物1,3-二酮组成。酮与三氟乙酸乙酯之间的反应结果与底物的结构密切相关,由烷基引起的空间拥挤有利于CC键的裂解。DFT研究进一步揭示,复分解反应是动力学上有利的途径。仅使用稍微过量的廉价三氟甲基化试剂,