Catalyst‐Controlled Divergent C3/C5 Site‐Selective C−H Arylation of 2‐Pyridylthiophenes

Abstract The development of a rational protocol to realize the complete regioselectivity and the capability to switch regioselectivity is an appealing yet challenging task. Herein, a regiodivergent C−H arylation of 2‐pyridylthiophenes has been demonstrated via the choice of Ru II and Pd II catalysts. The reactions proceeded smoothly in a good regioselective manner to afford the corresponding C3‐ and C5‐arylated thiophenes. Late‐stage diversification of biologically relevant scaffold derived from estrone and successful transformation of the products further highlighted the potential utility and importance of this synthetic strategy.