Even though aza-β-lactams have attracted interest because of their biological activity [1] and their utility as intermediates in organic chemistry (eg, for the generation of α-amino acids and hydantoins),[2–4] only limited progress has been reported with regard to the enantioselective synthesis of this family of heterocycles.[5] One attractive, convergent approach to the formation of aza-β-lactams is the [2+ 2] cycloaddition of a ketene with an ...
