New reactivity of hydroxyallylpyridyl derivatives as C-3 carbon nucleophiles

Hydroxyallylpyridyl derivatives exhibited a peculiar thermal behavior likely ascribed to the weak acidity of the picolinetype hydrogen atom on the C-1 carbon of the allyl residue, leading to allyl inversion products. The unprotected alcohol reacted as vinylogous picoline carbon nucleophile with stronglyactivated heterocyclic counterparts. A mechanistic rationale for this unprecedented reactivitywas proposed.