Photosensitized [4+2]- and [2+2]-Cycloaddition Reactions of N-Sulfonylimines

The synthesis of polycyclic compounds is of high interest due to the prevalence of these motifs in drugs and natural products. Herein, we report on the stereoselective construction of 3D bicyclic scaffolds and azetidine derivatives by modulation of N-sulfonylimines to achieve either [4+2]- or [2+2]-cycloaddition reactions. The utility of the method was established by further modulation of the product. Mechanistic studies are also included, which support reaction via Dexter energy transfer.

Automated summary

In this study, we achieved the stereoselective construction of 3D bicyclic scaffolds and azetidine derivatives by modulating N-sulfonylimines, allowing for either [4+2]- or [2+2]-cycloaddition reactions. The utility of the method was demonstrated through further modulation of the resulting products. Mechanistic studies supported a reaction mechanism involving Dexter energy transfer.