An Efficient Synthesis of 2,3-Aziridino-(gamma)-lactones from Azetidin-2-ones

An efficient synthesis of enantiopure 2,3-aziridino-(gamma)-lactones from azetidin-2-ones is described. Acid-catalyzed tandem intramolecular azetidinone ring opening followed by aziridine ring formation via elimination of a mesylate group is the key step in this synthesis. 2.3-Aziridino-(gamma)-lactones are important precursors for biologically important glutamic acid derivatives.