Metal-free synthesis of biaryls from aryl sulfoxides and sulfonanilides via sigmatropic rearrangement
作者:Akira Yoshida、Koichi Okamoto、Tomoyuki Yanagi、Keisuke Nogi、Hideki Yorimitsu
DOI:10.1016/j.tet.2020.131232
日期:2020.12
dehydrative metal-free construction of the corresponding unsymmetrical biaryls. The reaction would proceed via (1) the activation of aryl sulfoxide with the anhydride, (2) interrupted Pummerer reaction of the resulting arylsulfonium with sulfonanilide, (3) [3,3] sigmatropic rearrangement to cleave the transient S–N bond and to form the prospective biaryl C–C bond, and (4) global aromatization. The
用三氟乙酸酐处理芳基亚砜和磺酰苯胺导致相应的不对称联芳基的无脱水金属结构。反应将通过以下步骤进行:(1)用酸酐活化芳基亚砜,(2)中断所得芳基s与磺酰苯胺的Pummerer反应,(3)[3,3]σ重排以裂解瞬态S–N键并形成预期的联芳基C–C键,以及(4)整体芳构化。氨基保护基的选择是至关重要的,并且只有N-磺酰苯胺,即磺酰苯胺可以参与联芳基的形成。