Reduction of Disulfides with Copper. Preparation of Some Thioethers

Condensation of thiophenols with aryl halides using metallic copper as a reactant. Intermediation of cuprous thiophenolates

“…As shown in Table 1, the reaction of PhSH with Cu above 150°C gives CuSPh, PhSSPh, and Hz. Occurrence of the reaction [4] was supposed by several researchers (3)(4)(5), and it is now unequivocally established as shown in Nos. 5-8 in Table 1.…”

“…The dehydrogenative coupling of PhSH (eq. [3]) is evidently catalyzed by Cu, since heating of PhSH without Cu afforded considerably less PhSSPh. Partial formation of PhSPh at temperatures higher than 180°C is considered to be due to thermal degradation of CuSPh.…”

A Novel Synthesis of Allyl Sulfides by Organosamarium Reagents†

“…Sul®des are a class of useful synthetic intermediates, and many syntheses have been reported for their preparation, for example, the alkylation of thiols, 16 the reaction of alkyl halide with sodium sul®de, 17 addition of hydrogen sul®de to alkene, 18 reduction of disul®des with copper in the presence of halide, 19 reduction of sulfoxides with titanium(II) chloride, 20 deoxygenation of sulfoxides with triphenylphosphine± iodide±sodium iodide, 21 and the synthesis of allyl sul®des via allyldialkyltelluronium salts. 22 The advantages of this present method are readily available starting materials, simple operation, mild and neutral conditions, as well as good yield.…”