Lewis-Acid Catalyzed N-Acyliminium Ion Cyclodimerization: Synthesis of Symmetrical 1,4-Dioxanes.

Abstract The cyclodimerization reaction of N-substituted-5-hydroxy-pyrrolydinones promoted by BF3·Et2O and HCl to obtain symmetrical 1,4-dioxane derivatives was achieved in moderate to good yields, mild conditions, and short reaction times. These transformations render a promising alternative route that provides access to diverse 1,4-dioxane derivatives with a wide structural diversity.