Abstract
This report widens the repertoire of emerging Pd(I) catalysis to carbon-heteroatom, that is, C-S bond formation. While Pd(0) -catalyzed protocols may suffer from the formation of poisonous sulfide-bound off-cycle intermediates and lack of selectivity, the mechanistically diverse Pd(I) catalysis concept circumvents these challenges and allows for C-S bond formation (S-aryl and S-alkyl) of a wide range of aryl halides. Site-selective thiolations of C-Br sites in the presence of C-Cl and C-OTf were achieved in a general and a priori predictable fashion. Computational, spectroscopic, X-ray, and reactivity data support dinuclear Pd(I) catalysis to be operative. Contrary to air-sensitive Pd(0) , the active Pd(I) species was easily recovered in the open atmosphere and subjected to multiple rounds of recycling.