Palladium-Catalyzed, Multicomponent Approach to β‑Lactams via Aryl Halide Carbonylation

A palladium-catalyzed
multicomponent method for the synthesis of
β-lactams from imines, aryl halides, and CO has been developed.
This transformation proceeds via two tandem catalytic carbonylation
reactions mediated by Pd­(PtBu3)2 and provides a route to prepare these products from
five separate reagents. A diverse range of polysubstituted β-lactams
can be generated by systematic variation of the substrates. This methodology
can also be extended to the use of iodo-substituted imines to produce
novel spirocyclic β-lactams in good yields and selectivity.