Radical α,β-Dehydrogenation of Saturated Amides via α-Oxidation with TEMPO under Transition Metal-Free Conditions
作者:Mei-Mei Wang、Guo-Hui Sui、Xian-Chao Cui、Hui Wang、Jian-Ping Qu、Yan-Biao Kang
DOI:10.1021/acs.joc.9b00872
日期:2019.6.21
A transition metal-free radical process for the selective α,β-dehydrogenation of saturated amides under mild conditions is developed. Utilizing radical activation strategy, the challenging issue associated with the low α-acidity of amides is resolved. For the first time, α,β-unsaturated Weinreb amides and acrylamides could be efficiently prepared directly from corresponding saturated amides. Mechanistic
提出了在温和条件下对饱和酰胺进行选择性α,β-脱氢的过渡金属自由基方法。利用自由基活化策略,解决了与酰胺的低α-酸度有关的挑战性问题。首次可以直接从相应的饱和酰胺有效地制备α,β-不饱和Weinreb酰胺和丙烯酰胺。机理研究证实了这种转变的根本性质。还进行了两克规模的α,β-脱氢反应以证明该方法的实用性。