Intramolecular anodic olefin coupling reactions: Use of the reaction rate to control substrate/product selectivity

Look out-it's a trap! The anodic coupling of olefins with amine trapping groups to form proline and pipecolic acid derivatives with a quaternary α carbon atom (see scheme) was successful despite the significantly lower oxidation potential of the product relative to that of either functional group in the substrate: owing to the very fast cyclization, the oxidation potential of the substrate is lower than that of the product. Ts=p-toluenesulfonyl.