Synthesis of 2,4-Disubstituted Imidazoles via Nucleophilic Catalysis

A convergent, microwave-assisted protocol for the synthesis of disubstituted NH-imidazoles via nucleophilic catalysis is described. The substituted imidazoles are accessed via the intramolecular addition of a variety of amidoxime substrates to activated alkynes followed by a thermally induced rearrangement of the in situ generated O-vinylamid­oxime species. The unprotected imidazoles contain an aryl group at the 2-position as well as an ester moiety at the 4-position.