C–S/C–Br metathesis enabled by an Au–Pd alloy nanoparticle catalyst

<h2>Summary</h2> Metathesis via C–S bond oxidative addition and reductive elimination has recently witnessed considerable development as a functionalization of ubiquitous sulfur-containing molecules with the molecular frameworks intact. Despite the synthetic utilities, C–S/C–Br metathesis has not been reported so far because of the difficulties in managing both reversible C–Br oxidative addition/reductive elimination and sterically sensitive transmetalation between the oxidative adducts. Here, we report C–S/C–Br metathesis between thioethers and bromoarenes enabled by an Au–Pd alloy nanoparticle catalyst with a high Au/Pd ratio via utilization of unique multiple adsorption/active sites. This catalytic system is applicable to different thioethers and bromoarenes to afford both metathesis products in high yields, and late-stage bromination of C–S bonds in various thioethers possessing bioactive structures and depolymerization of polyphenylene sulfide to 1,4-dibromobenzene are also demonstrated.