Copper-Catalyzed Amination of Aryl Chlorides under Mild Reaction Conditions

We report a mild method for the copper-catalyzed amination of aryl chlorides. Key to the success of the method was the use of highly sterically encumbered <i>N</i>¹,<i>N</i>²-diaryl diamine ligands which resist catalyst deactivation, allowing reactions to proceed at significantly lower temperatures and with a broader scope than current protocols. A sequence of highly chemoselective C-N and C-O cross-coupling reactions were demonstrated, and mechanistic studies indicate that oxidative addition of the Cu catalyst to the aryl chlorides is rate-limiting. We anticipate that the design principles disclosed herein will help motivate further advances in Cu-catalyzed transformations of aryl chlorides.