Isothiourea-Catalyzed [2 + 2] Cycloaddition of C(1)-Ammonium Enolates and -Alkyl Isatins.

Enantioselective [2 + 2] cycloaddition of C(1)-ammonium enolates generated catalytically using the isothiourea HyperBTM with -alkyl isatins gives spirocyclic β-lactones. ring opening with an amine nucleophile generates isolable highly enantioenriched products in up to 92:8 dr and in >99:1 er.

Multicomponent alkene azidoarylation by anion-mediated dual catalysis.

Molecules that contain the β-arylethylamine motif have applications in the modulation of pain, treatment of neurological disorders and management of opioid addiction, among others, making it a privileged scaffold in drug discovery. De novo methods for their assembly are reliant on transformations that convert a small class of feedstocks into the target compounds via time-consuming multistep syntheses. Synthetic invention can drive the investigation of the chemical space around this scaffold to further expand its capabilities in biology.