N-amides, Versatile Amidoalkylation Reagents. Part 4 A New Synthetic Route to 4H-1,3-Oxazines

Article abstract of DOI:10.1002/prac.19923340203

A variety of 2,4,6-tri- and 2,4,5,6-tetrasubstituted 4H-1,3-oxazines (7a-i) were synthesized in excellent yields by the reaction of acetylenes (5) in the presence of aluminum chloride with N-<1-(benzotriazol-1-yl)alkyl>amides 4, themselves readily prepare