Ugi-smiles access to quinoxaline derivatives

Two different Ugi-Smiles post-condensations strategies have been used for new three and four-component formation of quinoxaline scaffolds. In the first approach, a one-pot hydrogenation-cyclization affords the heterocycle with loss of the initial isocyanide moiety. In the second one, the use of o-iodonitrophenol as starting phenol, coupled with copper catalyzed cyclization gave us similar quinoxaline derivatives resulting from a four coupling.