Regiocontrolled Direct C−H Arylation of Indoles at the C4 and C5 Positions

Abstract An effective and practical strategy has been established for the direct and site‐selective arylation of indoles at the C4 and C5 positions with the aid of a readily accessible, cheap, and removable pivaloyl directing group at the C3 position. This transformation shows good functional‐group tolerance and could serve as a powerful synthetic tool for the synthesis of medicinally relevant compounds. This method and those developed in previous research together enable the regiocontrolled direct arylation of indole at each C−H bond without prefunctionalization of the reactive sites.