Pd(II)-Catalyzed Hydroxylation of Arenes with 1 atm of O2 or Air

Abstract
Pd(II)-catalyzed ortho-hydroxylation of variously substituted benzoic acids under 1 atm of O2 or air is achieved under nonacidic conditions. Extensive labeling studies support a direct oxygenation of aryl C−H bonds with molecular oxygen.