Divergent synthesis of functionalized dihydropyridines and pyrroles via metal-free one-pot domino reactions of a gem-disubstituted propargyl amine and an alkynyl sulfone

[Display omitted] Reaction of an 2-amino-2-ethynylmalonate derivative with an ethynyl sulfone allowed metal-free divergent synthesis of 1,6-dihydropyridines (DHPs) and 3,5-disubstituted pyrroles in one-pot. This facile atom-economical domino process involves hetero-conjugate addition and subsequent propargyl aza-Claisen-type rearrangement, followed by either 6π-aza-electrocyclization or 5-exo-dig cyclization. This approach enabled the simple and solvent-dependent divergent syntheses of densely functionalized 1,6-DHPs and pyrroles at ambient temperature.