Easy access to α-amino β-oxo esters from β-enamino esters

Article abstract of DOI:10.1016/S0040-4039(99)00760-1

N-Substituted α-amino β-oxo esters have been obtained by amination of β-enamino esters with ethyl N-[(4-nitrobenzenesulphonyl)oxy]carbamate (NsONHCO₂Et), in the absence of added bases. The use of optically active pyrrolidines with C₂ symmetry as chiral auxiliaries induces diastereoselectivities up to 80%.