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

Enantioselective [2 + 2] cycloaddition of C(1)-ammonium enolates generated catalytically using the isothiourea HyperBTM with N-alkyl isatins gives spirocyclic ß-lactones. In situ 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 ß-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 discovery1,2. 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 syntheses3-5. Synthetic invention can drive the investigation of the chemical space around this scaffold to further expand its capabilities in biology6-9. Here we report the development of a dual catalysis platform that enables a multicomponent coupling of alkenes, aryl electrophiles and a simple nitrogen nucleophile, providing single-step access to synthetically versatile and functionally diverse ß-arylethylamines. Driven by visible light, two discrete copper catalysts orchestrate aryl-radical formation and azido-group transfer, which underpin an alkene azidoarylation process. The process shows broad scope in alkene and aryl components and an azide anion performs a multifaceted role both as a nitrogen source and in mediating the redox-neutral dual catalysis via inner-sphere electron transfer10,11. The synthetic capabilities of this anion-mediated alkene functionalization process are likely to be of use in a variety of pharmaceutically relevant and wider synthetic applications.