Reactivity of Glutaconamides Within [2]Rotaxanes: Mechanical Bond Controlled Chemoselective Synthesis of Highly Reactive -KetoAmides and their Light-Triggered Cyclization

Glutaconamide-based [2]rotaxanes are efficiently oxidized to the respective interlocked alpha-ketoamides, whereas their non-interlocked threads afford hydroxycyclohexene tetraamides under similar reaction conditions. These results showcase the mechanically interlocking of highly reactive substrates as a powerful tool for controlling their chemical behavior. Inside the macrocycle and under irradiation with light, the alpha-ketoamide threads convert, in a divergent manner, into the corresponding interlocked hydroxy-beta-lactams or oxazolidinones by two modes of Norrish/Yang type-II intramolecular cyclizations, processes that are efficiently chemocontrolled by the mechanical bond.