Diastereoselective\nAccess to Ester-Substituted <i>cis</i>-Phenanthridinones\nvia Hydrogen Atom Transfer-Involved\n1,7-Enyne Bicyclization

An organophotoredox-catalyzed 1,7-enyne bicyclization\nfor the cis-diastereoselective\nsynthesis of ester-substituted phenanthridinones has been achieved\nthrough radical cascade cyclization involving 1,6-hydrogen atom transfer.\nThis transition-metal- and oxidant-free one-pot protocol generates\nthree distinct C–C bonds and two quaternary carbon centers.