Catalyst-Controlled Chemodivergent C-H Functionalization of 2-Pyridylthiophenes with Allylic Alcohols

Abstract

A catalyst-controlled chemodivergent C–H functionalization of 2-pyridylthiophenes using allylic alcohols as versatile coupling partners is reported. Modulation of the catalytic system enables selective access to two distinct reaction pathways from identical substrates. A Rh-based catalyst promotes redox-neutral C–H alkylation to afford β-aryl ketones via C–H activation, alkene insertion, and subsequent tautomerization, whereas a Co-based system enables dehydrative C–H allylation through β-hydroxide elimination, retaining the olefinic moiety. This protocol achieves regioselective C3-functionalization in a step- and atom-economical manner, overcoming the inherent chemoselectivity challenges of free allylic alcohols and providing efficient access to structurally diverse heteroaromatics.