Based on previous work from our group and literature precedence, we commenced our initial investigation using iodonium salt 1a, molecular sulfur (2a), and K2CO3 as a base in DMSO at 80 °C. The desired product 3a was not detected, but 11% of the diaryl ether 3a' was observed instead (Table , entry 1). Changing the sulfur source to thiourea 2b under the same conditions allowed the formation of 3a in 26% yield (entry 2). The more nucleophilic sulfur reagents potassium thioacetate 2c and potassium ethyl xanthogenate 2d gave significantly increased reactivity already at room temperature. Furthermore, the formation of 3a' was entirely suppressed and external base was no longer necessary (entries 3-5). Other polar solvents proved to be effective for this transformation (entries 6,7), and significantly improved yields were obtained in reactions performed in the absence of light (entries 8-10). Upon increased reaction scale, sulfide 3a was isolated in excellent yield at 40 °C in DMF (entry 11), whereas surprisingly poor results were obtained in acetone (entry 12). Next, we investigated the generality of our protocol using the conditions in entry 11 (Scheme 2A). Diaryliodonium salts 1 bearing alkyl groups in the ring displayed excellent reactivity, producing diaryl sulfides 3b-3d in high yields. Haloarenes are primary precursors for metal-catalyzed synthesis of sulfides, which limits the synthesis of the corresponding halide-substituted derivatives. Importantly, our route can sustain halogen substituents in the aryl ring of 1, providing moderate to excellent yields of diaryl sulfides 3e-3h. (%) yield 3a' (%) 8 2d -DMF rt 99 n.d.