Iodomethane in C1 chemistry: application in palladium-catalyzed [2 + 2 + 1] annulation

An efficient palladium-catalyzed [2 + 2 + 1] annulation of 3-iodochromones, bridged olefins, and iodomethane is described, affording a range of chromone-containing polycyclic compounds. Additionally, the corresponding deuterated products were smoothly obtained with iodomethane-