Thiol adduct, dehydrogenation

The results of Table 10 confirm that the Fe (ROOH) + adducts are effective dehydrogenation agents for substrates such as cyclohexadienes, substituted hydrazines, catechols, and thiols. For PhNHNHPh and 3,5-t-Bu2-l,2-(OH)2C6H2, the reaction efficiencies are comparable for HOOH and m-C1C6H4C(0)00H as the oxidant but somewhat reduced for... 

Scheme 9.13). The process starts with a Michael reaction of a keto-thiol with a vinylphosphonium salt. The Michael adduct is then reacted under the usual conditions of the Wittig synthesis to form a dihydrothiophene. This is easily oxidized (dehydrogenated) to the thiophene with the mild agent chloranil, which is reduced to tetrachlorohydroquinone. 

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