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Phosphorothioate has proven to be a useful skeleton in organic synthesis as a valuable building block, in pharmaceuticals and pesticides due to its biological and physical properties. In particular, S-aryl phosphorothioate represents an important structural element in antiproliferative agents (A), pesticides (B), antibacterials (C), curing accelerators (D), antistatic agents (E), and anticholinesterases (F) (Scheme 1). However, the investigation on building such a structure has lagged behind. Hence, a rapid, efficient and practical access to S-aryl phosphorothioates is highly desired. Traditional procedures to synthesize S-aryl phosphorothioates involved the reaction of trialkyl phosphites with sulfenyl chlorides by chlorinating the mercaptan or disulfide with sulfuryl chloride, and the coupling of H-phosphonates with disulfides by complicated electrosynthetic processes. Witt’s group obtained phosphorothioates by the treatment of (5,5-dimethyl-2-thioxo-1,3, 2-dioxaphosphorin-2-yl) disulfanyl derivatives with trimethyl phosphate, in which the substrate was limited to trimethyl phosphate. Very recently, Liu and co-workers reported a two-step process to synthesize phosphorothioates from thiols and phosphonates promoted by N-chlorosuccinimide. Transition-metal-catalyzed direct coupling reactions of dialkyl phosphonates with organic disulfides (or benzenethiols) have provided an alternative protocol to synthesize S-aryl phosphorothioates, in which a base is required. In summary, some problems exist with these procedures, such as: (1) requirement of complicated or foul-smelling starting materials, which are not commercially available and (2) a narrow scope of substrates. The remaining challenge is to develop a general and applicable strategy for a variety of S-aryl phosphorothioates. Therefore, we focus our current research interests on building such a structure. Herein, we disclose a simple and practical procedure to synthesize various S-aryl phosphorothioates via copper-catalyzed reductive cross-coupling reactions of commercially available aryl sulfonyl chlorides with dialkyl phosphonates under an air atmosphere and base-free conditions (Scheme 2). We initiated our investigation with the reaction of tosyl chloride (1a) with dimethyl phosphonate (2a) as a model reaction to identify the optimal reaction conditions. Several parameters, such as catalyst sources, solvents and reaction temperature Scheme 1 Several examples illustrating the importance of S-aryl phosphorothioates.