Ruthenium(II)-catalyzed synthesis of hydroxylated arenes with ester as an effective directing group.

An unprecedented Ru(II) catalyzed ortho-hydroxylation has been developed for the facile synthesis of a variety of multifunctionalized arenes from easily accessible ethyl benzoates with ester as an efficient directing group. Both the TFA/TFAA cosolvent system and oxidants serve as the critical success factors in this transformation. The reaction demonstrates excellent reactivity, good functional group tolerance, and high yields.