Palladium-Catalyzed Oxidations: Inhibition of a Pd−H Elimination by Coordination of a Remote Carbon−Carbon Double Bond

Under oxidative conditions that use an anionic palladium salt as catalyst, cis - endo -2,3-bis(hydroxymethyl)bicyclo[2.2.1]hept-5-ene affords the corresponding exo -lactol, while cis - endo -2,3-bis(hydroxymethyl)bicyclo[2.2.1]heptane provides the expected lactone. Mechanistic considerations explain how the presence of the C C bond blocks the oxidation at the lactol in the first case.