Preparation and electrophilic cyclization of multisubstituted dienamides leading to cyclic iminoethers

Stereodefined multisubstituted dienamides can be concisely prepared in high yields by direct addition of 1-lithiobutadiene derivative to both N-aryl and N-alkyl isocyanates. It is shown that when treated with 12 N aqueous HCl, dienamides underwent efficient and selective electrophilic cyclization to afford cyclic imidate derivatives.