Divergent Synthesis Of Functionalized Dihydropyridines And Pyrroles Via Metal-Free One-Pot Domino Reactions Of A Gem-Disubstituted Propargyl Amine And An Alkynyl Sulfone

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 6 pi-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. (C) 2021 Elsevier Ltd. All rights reserved.