A one-pot, efficient, and odorless synthesis of symmetrical disulfides using organic halides and thiourea in the presence of manganese dioxide and wet polyethylene glycol (PEG-200)

4,4′-Azopyridine as an easily prepared and recyclable oxidant for synthesis of symmetrical disulfides from thiols or alkyl halides(tosylates)/thiourea

“…This observation is similar to previous reports in which trace amounts of water can help to promote the conversion of alkyl halides into disulfides. [63,69,72] Aliphatic alkyl halides were well tolerated in these optimized one-pot conditions, and the reactions of n-butyl bromide (5b), n-octyl iodide (5c) and n-octyl bromide (5d) with thiourea and 4,4'-azopyridine 2c resulted in the desired products in 81-91% yields (Entries 2-4). Excellent yields were also obtained when benzylic (Entries 5-7) and allylic substrates (Entries 8-10) were used as starting materials.…”

“…[55][56][57][58][59][60][61][62] Another commonly used method of disulfide formation involves the reaction of alkyl halides with sulfur transfer reagents in the presence of an oxidant. [63][64][65][66][67][68][69][70][71][72][73][74] The reaction was claimed to be the oxidation of in situ-generated thiols which are formed from alkyl halides and the sulfur transfer reagent. This strategy decreases often encountered problems such as unpleasant odor of thiols and tedious work-up that is confronted when using methods involving direct oxidation of thiols.…”

Reactivity of Nitroxyl-Derived Sulfinamides

“…35 Briefly, bis(2-phenylethyl) disulfide was generated from (2-bromoethyl)benzene using thiourea, MnO 2 , and Na 2 CO 3 as described previously. 36 The disulfide was reacted with 1.5 equiv of N-bromosuccinimide (NBS) in methanol to form the corresponding methyl sulfinate. After the mixture had been stirred at room temperature for 3 h, the mixture was diluted with CH 2 Cl 2 , washed with a saturated NaHSO 3 solution, and extracted with a saturated solution of NaHCO 3 .…”

Schiff base complex of Cu immobilized on MCM-41 as reusable catalyst for efficient oxidative coupling of thiols and oxidation of sulfides using hydrogen peroxide

“…Moreover, they are also relatively more stable in organic reactions such as oxidation, alkylation and acylation compared to the corresponding free thiols, therefore the thiol group can be protected as a disulfide [26]. Additionally, in organic synthesis, S-S bonds are used for the synthesis of organo-sulfur compounds via C-S bond formation [28].…”

“…For these reasons, many methods have been developed over the years to find efficient these organic transformations [18][19][20][21][22][23][24][25][26][27][28][29][30][31][32]. For example, many methods have been reported in the presence of various catalysts and using different oxidant (e.g.…”