Unified Photoredox Strategy for Selective Access to Hydroisoquinoline and Benzosultam via Tether Modulation of Allylamine

Hydroisoquinoline and benzosultam motifs represent privileged heterocyclic frameworks with broad pharmacological relevance. We report a divergent photoredox strategy that enables selective access to both scaffolds from a simple precursor. The transformation proceeds via radical addition to an unactivated olefin followed by a domino cyclization. While conventional reactivity strongly favors hydroisoquinoline formation, we discovered that chain-length modulation imposes ring strain on the arene pathway, thereby suppressing the competing cyclization and promoting the challenging sulfonyl-arene closure. This strain-guided approach offers a unified entry to hydroisoquinolines and benzosultams under mild conditions, expanding the toolkit for heterocycle synthesis.