Direct Amidation of 2‐Methylquinolines With Anilines Under Transition‐Metal‐Free Conditions Using Air as the Sole Oxidant

Abstract

A facile oxidative coupling of 2‐methylquinolines with anilines that uses air as the sole oxidant is described. The reaction affords a straightforward route to aromatic amides under transition‐metal‐free conditions. With potassium tert‐butoxide as the promoter, the direct amidation reaction proceeds smoothly at a lower reaction temperature relative to reported protocols (75°C vs. 120°C–130°C). Notably, the replacement of 2‐methylquinoline with 2‐quinolinecarboxaldehyde, a putative intermediate in previous studies, for the coupling with aniline resulted in a markedly lower yield of the target aromatic amide (59% vs. 84%). This unexpected finding offers new possible considerations for relevant research in organic chemistry.