Enantioselective synthesis of aryl Sulfoxides via palladium-catalyzed arylation of sulfenate anions

Arylation of various sulfenate anions generated from,ss-sulfinyl esters by retro-Michael reaction in the presence of palladium(0) and enantiopure ligands gave the corresponding aryl sulfoxides in enantio-enriched form. The Josiphos-type ligand (R)-(S)-PPF-t-Bu-2 turned out to be the best ligand tested, allowing ee's up to 83% in a predictable sense.