New methodology for the preparation of N-tosyl aziridine-2-carboxylates

N-Tosyl aziridine-2-carboxylate methyl esters were prepared from methyl N-tosyl-l-serinate or N-tosyl-l-threoninate, tosyl chloride, and K2CO3, under phase-transfer catalysis (PTC) conditions. The same methodology, as applied to the tert-butyl N-tosyl-l-serine amide, afforded the corresponding newly prepared aziridine-2-carboxamide, as an enantiomerically pure compound.