F<sup>–</sup>-Free Deoxyhydrotrifluoromethylation of α-Keto Esters with Ph<sub>3</sub>P<sup>+</sup>CF<sub>2</sub>CO<sub>2</sub><sup>–</sup>: Synthesis of α–CF<sub>3</sub>-Substituted Esters
作者:Ying Zheng、Yimin Jia、Yuan Yuan、Zhong-Xing Jiang、Zhigang Yang
DOI:10.1021/acs.joc.0c01518
日期:2020.8.21
direct deoxyhydrotrifluoromethylation of α-keto esters with a difluoromethylating reagent has been achieved, in which the employment of water can promote the dissociation of the CF2 group to form a CF3 moiety, which provides the successful transformation. The current protocol demonstrates one of the most practical approaches to generate α-trifluoromethyl esters with a broad substrate scope and high functional
三氟甲基化的化合物通常是通过使用CF 3 SiMe 3和NaSO 2 CF 3,梅本氏试剂和Togni试剂通过三氟甲基化反应获得的。在此,已经实现了用二氟甲基化试剂的α-酮酯的外部无氟阴离子的直接脱氧氢三氟甲基化,其中水的使用可以促进CF 2基团的离解以形成CF 3。部分,提供成功的转化。当前方案证明了一种最实用的方法来生产具有广泛的底物范围和高官能团相容性的α-三氟甲基酯,其中它适用于生物活性化合物的后期修饰,并且可以轻松按比例放大。机理研究表明,原位生成的宝石-二氟烯烃中间体会被水分解,从而生成酰基氟和HF。