An unusual cleavage of a C–S bond with concurrent S-arylation under palladium–copper catalysis

3-[2-(N-p-Toluenesulfonyl)aminophenylthio]prop-1-yne (4) reacted with aryl iodides 5–14 under palladium–copper catalysis to afford (2-arylthio)-p-toluenesulfonanilide (15–23) in moderate to good yields (54–64%) through unusual depropargylation and S-arylation reactions.