[2+2] Photocycloaddition reactions of sulfinylamines with alkenes to access β-sultam derivatives

Nature Chemistry, Published online: 07 May 2026; doi:10.1038/s41557-026-02146-1 Although [2+2] photocycloadditions are pivotal for four-membered ring synthesis, such intermolecular protocols for the synthesis of β-sultam derivatives remain challenging. Now an unconventional visible-light-mediated [2+2] photocycloaddition reaction between alkenes and sulfinylamines gives access to β-sultam derivatives. The approach features triplet energy transfer of sulfinylamines, enabling access to a broad ran