Rearrangement of Nα-Protected l -Asparagines with Iodosobenzene Diacetate. A Practical Route to β-Amino- l -alanine Derivatives

A general synthetic method for the Hofmann rearrangement of protected asparagines has been developed. Reaction of asparagine derivatives with iodosobenzene diacetate (PIDA) in mixed solvents produces β-amino- l -alanines in good yield. Advantages over the commonly used reagent bis(trifluoroacetoxy)iodobenzene have been discussed.