Palladium-Catalyzed Aryl C(sp2)-H Bond Hydroxylation of 2-Arylpyridine Using TBHP as Oxidant

An efficient synthesis of phenols via Pd-catalyzed, pyridyl-directed homogeneous hydroxylation of the aryl C-H bond was developed, in which tert-butyl hydroperoxide was used as the sole oxidant. The method had a broad group tolerance and was available for both electron-rich and electron-deficient substrates. The reaction of a series of 2-arylpyridine derivatives gave the ortho-hydroxylation products in moderate to good yields.