Catalyst‐Controlled Regiodivergent C−H Alkynylation of 2‐Pyridylthiophenes

Abstract Different catalysts are presented to overcome or augment a substrate's innate regioselectivity. Rhodium was found to overcome the innate C3‐selectivity via chelation‐assisted rhodation. Conversely, palladium was found to enhance the innate C5‐selectivity via electrophilic palladation. These reactions allow for the formation of a diverse range of synthetically versatile C3‐ and C5‐alkynylated products from 2‐pyridylthiophenes. Notably, this strategy was successfully employed in the straightforward synthesis of π‐extended functionalized 2‐pyridylthiophenes, which could be converted into more valuable compounds.