Pd/BIPHEPHOS is an Efficient Catalyst for the Pd‐Catalyzed S‐Allylation of Thiols with High n‐Selectivity

The Pd‐catalyzed S‐allylation of thiols with stable allylcarbonate and allylacetate reagents offers several advantages over established reactions for the formation of thioethers. We could demonstrate that Pd/BIPHEPHOS is a catalyst system which allows the transition metal‐catalyzed S‐allylation of thiols with excellent n‐regioselectivity. Mechanistic studies showed that this reaction is reversible under the applied reaction conditions. The excellent functional group tolerance of this transformation was demonstrated with a broad variety of thiol nucleophiles (18 examples) and allyl substrates (9 examples), and could even be applied for the late‐stage diversification of cephalosporins, which might find application in the synthesis of new antibiotics.