Preparation of chiral 3-unsubstituted β-lactams from 3-hydroxy β-lactams by using the alkoxyketene-imine cycloaddition reaction as an approach to the azetidinone ring: A formal synthesis of the carbapenem antibiotic (+)-PS-5.

1. Palomo, C.
2. Cossío, F.P.
3. Ontoria, J.M.
4. Odriozola, J.M.