One-Pot Three-Component Synthesis of Tetrasubstituted N-H Pyrroles from Secondary Propargylic Alcohols, 1,3-Dicarbonyl Compounds and tert-Butyl Carbamate

摘要

Several tetrasubstituted N-H pyrroles, functionalized with ester or ketone groups at C-3 position, were prepared by one-pot coupling of secondary propargylic alcohols with 1,3-dicarbonyl compounds and tert-butyl carbamate, via in situ deprotection of the corresponding pentasubstituted N-Boc pyrroles. The three-component coupling process was promoted by the combined use of the 16-electron ruthenium(H) catalyst [Ru(eta(3)-2-C3H4Me)(CO)(dppf)][SbF6] (dppf = 1,1'-bis(diphenylphosphino)ferrocene) and trifluoroacetic acid (TFA).