Nitrative Cyclization of 1‐Ethynyl‐2‐(vinyloxy)benzenes to Access 1‐[2‐(Nitromethyl)benzofuran‐3‐yl] Ketones Through Dioxygen Activation

Abstract A new metal‐free method for the nitrative cyclization of 1‐ethynyl‐2‐(vinyloxy)benzenes with tert ‐butyl nitrite ( t‐ BuONO), air and water at room temperature is presented, in which an oxygen atom is introduced into the carbon‐carbon triple bond to form a new carbonyl group through dioxygen activation. magnified image