Formal synthesis of (-)-aphanorphine using sequential photomediated radical reactions of dithiocarbamates

Time to change the light bulb: An alkyl dithiocarbamate, itself formed through a photoinitiated group-transfer cyclization of a carbamoyl radical, undergoes a second photomediated radical process initiated with a different light source. These two reactions, which proceed through the same cyclohexenyl radical intermediate, are key steps in a new asymmetric synthesis of the alkaloid aphanorphine. TEMPO=2,2,6,6-tetramethyl-1-piperidinoxyl radical.