The Pd/C-catalyzed coupling reactions of thiol esters 1 with a zinc reagent 2 were accomplished in the presence of DMF leading to the polyfunctional ketones 3 in good yields under mild reaction conditions. The protocol was applied to the coupling reaction of a thiolactone 4c with a zinc reagent 2 to provide, after dehydration, a dehydrobiotin derivative 5c in 94% yield.
