Zinc Trifluoromethanesulfonate-Catalyzed para-Selective Amination of Free Anilines and Free Phenols with Quinoneimides.

An efficient zinc-catalyzed amination of free anilines and free phenols with quinoneimides has been disclosed, which proceeds smoothly under simple and mild conditions. The para-selective amination is accomplished on the anilines and phenols via a 1,6-addition pathway, leading to C-N bond formation. The developed protocol offers a promising approach not only for the construction of structurally diverse p-phenylenediamine compounds with excellent yields but also for the synthesis of the para-amination of free phenol derivatives with good to excellent yields. This protocol also extends the application of the quinoneimide-involved 1,6-addition reaction.