Divergent Pathways in C–H Functionalization of Furfural Derivatives with Cobalt-Hydride Catalysis

This study reports the first cobalt-catalysed C–H functionalization of furfural derivatives, demonstrating distinct reactivities based on the substrate. Furfurylimines enable selective C5–H alkenylation with alkynes, whereas free aldehydes undergo decarbonylative C2-alkenylation. These results establish a novel strategy using formyl groups as traceless handles for cobalt- catalysed C–C bond formation.