Benzofuran oxide (1) reacts with a variety of enones and amines to give quinoxaline monoxides. The nature of the amine determines the regiochemistry of the product: secondary amines give a type 4 product and primary amines give a type 5 product. Reaction of 1, cinnamaldehyde, and morpholine gave both 4a and 8a. The regiochemistry of these N- oxide products is discussed in terms of intermediate 11. Principal limitations of these ...