Magic Blue-Initiated S2-Type Ring Opening of Activated Aziridines: Friedel-Crafts-Type Alkylation of Electron-Rich Arenes/Heteroarenes.

A transition metal-free, atom-economical, and highly stereospecific synthetic approach to Friedel-Crafts-type alkylation of arenes/heteroarenes has been developed. The protocol involves the catalytic aminium radical-cation salt (Magic Blue)-initiated S2-type nucleophilic ring opening of activated aziridines with arenes/heteroarenes to give the corresponding 2,2-diarylethylamines up to 99% yield and 85% ee (for nonracemic aziridines) in a very short reaction time. Moreover, on reaction with 1,3-dimethylindole and benzofuran, aziridines undergo domino-ring-opening cyclization (DROC) to give the various biologically significant heterocyclic scaffolds in moderate to good yields.

Catalytic Aminium Radical-Cation Salt (Magic Blue)-Initiated S2-Type Nucleophilic Ring-Opening Transformations of Aziridines.

A simple and atom economic protocol for the construction of C-X/C-C bonds via catalytic aminium radical-cation salt (Magic Blue)-initiated S2-type nucleophilic ring-opening transformations of racemic and nonracemic aziridines with different hetero and carbon nucleophiles to afford various amino ethers, thioethers, and amines in up to 99% yield, and with perfect enantiospecificity for some substrates but reduced ee with others (for nonracemic aziridines), is developed. This aminium radical-cation salt-initiated, S2-type nucleophilic ring-opening strategy, along with various cyclization protocols, is employed to synthesize various biologically significant compounds.