Total Syntheses of Grandilodines A and C and Lapidilectam via a Photoredox-Catalyzed Decarboxylative (6 + 2) Radical Annulation

Herein, a unified approach to the concise total syntheses of grandilodine A, grandilodine C, and lapidilectam is described. Key steps in this synthesis include a sequential reductive amination/lactamization to assemble the pyrrolidinone structure, a gold-catalyzed 8-endo-dig cyclization to forge the central eight-membered ring, an effective photoredox-catalyzed decarboxylative (6 + 2) radical annulation to construct the rigid azabicyclic [4.2.2] framework featuring three contiguous stereocenters, and a late-stage modification of the lactam ring.