Synthesis of polysubstituted pyrroles from activated alkynes and n-propargylamines through base-catalyzed cascade reaction

Article abstract of DOI:10.1002/ejoc.201500166

A novel K₃PO₄-catalyzed synthesis of polysubstituted pyrroles by a Michael addition/alkyne carbocyclization of activated alkynes and N-propargylamines has been developed. This transition-metal-free cascade process represents an environmental friendly and efficient way to construct polysubstituted pyrroles in good yields. Catalyzed by CsF, a Michael addition/aza-Claisen rearrangement/cyclization sequential process has been achieved to selectively synthesize pyrroles in moderate yields. An efficient method for the synthesis of polysubstituted pyrroles from activated alkynes and N-propargylamines has been developed. This cascade process represents an atom- and step-economical way to construct a range of polysubstituted pyrroles and involves base-catalyzed Michael addition/alkyne carbocyclization or Michael addition/aza-Claisen rearrangement/cyclization.