Silver‐Promoted Coupling of Carbon Dioxide, <i>o</i> ‐Alkynylanilines and Diaryliodonium Salts: Straightforward Access to 4‐Aryloxy‐2‐quinolinones

Abstract

Abstract A silver‐promoted three‐component reaction of carbon dioxide, o ‐alkynylanilines and diaryliodonium salts using 1,4‐diazabicyclo[2.2.2]octane (DABCO) as the base has been developed for the first time, which provides an efficient and straightforward protocol for the synthesis of a wide range of 4‐aryloxy‐substituted 2‐quinolinones in moderate to excellent yields. Diverse functional groups such as halo, trifluoromethyl, cyano and nitro are well tolerated. Mechanistic studies indicated that 4‐hydroxyl‐2‐quinolinone generated in‐situ from o ‐alkynylanilines and carbon dioxide might be the key intermediate for the reaction.