Reaction of 5-isonitroso-2,2-dimethyl-1,3-dioxane-4,6-dione with various ketones under reflux in toluene gives 3-oxazolin-5-one 3-oxides (cyclic nitrones) via a nitrosoketene intermediate generated from the isonitroso derivative. The cyclic nitrones can be used for the stereoselective [3 + 2] dipolar cycloaddition to electron-rich olefins under high pressure to produce fused isoxazolidines. These isoxazolidines, in turn, are versatile intermediates for the stereoselective preparation of substituted α-amino acids.
ASJC Scopus subject areas
- Organic Chemistry