A cooperative Lewis acid/photocatalytic reduction of salicylaldehyde-derived arylidene malonates provides access to a versatile, stabilized radical anion enolate. Using these unusual umpolung operators, we have developed a novel route to access densely functionalized carbo- and heterocycles through a radical annulation addition pathway.
†Electronic supplementary information (ESI) available. CCDC 1835356. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c9sc00302a