Metal-Free Halonium Mediated Acetate Shifts of Ynamides To Access α-Halo Acrylamides/Acrylimides

A metal-free acetate shift of 3-acetoxy ynamides to access α-iodo, bromo, and chloro acrylamides/acrylimides under very mild conditions is demonstrated. The inherent alkyne activation of ynamides is sufficient to ensure the α-halo acrylamides/acrylimides in high yields without the addition of a catalyst. In all cases high Z-stereoselectivity is observed.

本研究证实，可通过3-乙酰氧基炔酰胺（3-acetoxy ynamides）的无金属乙酸酯重排（acetate shift）反应，在极温和的条件下制备α-碘代、溴代及氯代丙烯酰胺/丙烯酰亚胺（acrylimides）。炔酰胺自身固有的炔烃活化效应足以使该反应无需额外添加催化剂，即可获得高产率的α-卤代丙烯酰胺/丙烯酰亚胺产物，且所有反应均表现出高Z型立体选择性。