One-pot three-component catalytic synthesis of fully substituted pyrroles from readily available propargylic alcohols, 1,3-dicarbonyl compounds and primary amines

A simple and highly efficient method for the preparation of fully substituted pyrroles, from readily accessible secondary propargylic alcohols, 1,3-dicarbonyl compounds and primary amines, has been developed. The one-pot multicomponent reaction, which is catalysed by the system [Ru(eta(3)-2-C3H4Me)(CO)(dppf)][SbF6]/CF3CO2H (dppf: 1,1'-bis(diphenylphosphanyl)ferrocene), involves initial propargylation of the 1,3-dicarbonyl compound promoted by CF3CO2H and subsequent condensation between the resulting gamma-keto alkyne and the primary amine to afford a propargylated beta-enamino ester or ketone, which undergoes a ruthenium-catalysed 5-exo-dig annulation to form the final pyrrole.