Aryl disulfides

Pitt Consol 500 aryl disulfides in petroleum oil peptizer shortens devulcan-izing time by oxidizing mbber bonds... 

Another way to prepare fluorinated sulfides is the photochemical alkylation of sulfides or disulfides by perfluoroalkyl iodides [69, 70, 71] (equations 62-64). Reaction of trifluoromethyl bromide with alkyl or aryl disulfides in the presence of a sulfur dioxide radical anion precursor, such as sodium hydroxymethanesulfi-nate, affords trifluoromethyl sulfides [72] (equation 65). 

A hydroxy and an arylthio group can be added to a double bond by treatment with an aryl disulfide and lead tetraacetate in the presence of trifluoroacetic acid." Manganese and copper acetates have been used instead of Pb(OAc)4. ° Addition of the groups OH and RSO has been achieved by treatment of alkenes with O2 and a thiol (RSH)." Two RS groups were added, to give vie- dithiols, by treatment of the alkene with a disulfide RSSR and Bp3-etherate."° This reaction has been carried... 

Arylthioindole-2-carboxylic acids 303, obtained from aryl disulfides and indole-2-carboxylic acids, afford tetracyclic 5H-indolo-[3,2-fc][l,5]benzothiazepin-6(7H)-ones 304 on treatment with EDC-DMAP (Scheme 65 (1998MI139)). 

Alkyl disulfides Alkyl sulfides Elemental sulfur Aryl disulfides Aryl sulfides Thiophenes... 

The lifetime of the RSSR radical anions is usually very short on the microsecond timescale in water. However, they have been detected and characterized by time-resolved optical methods. In one early study, y irradiation of matrices containing alkyl and aryl disulfides provided spectroscopic evidence for the formation of the corresponding radical anions. Subsequently, the formation of RSSR radical anions has been well documented, particularly by EPR, flash photolysis, and pulse radiolysis. In fact, 2a/ a three-electron bonded radical anion species, particularly from sulfur compounds, constitute significant and interesting intermediates. The RSSR radical anions may be obtained from different approaches. One is by one-electron reduction of disulfides (equation 75), such as by pulse radiolysis. However, the most common approach is by association of RS and RS (equation 79). ... 

Reduction, see also Hydrogenation electrolytic, see Electrolysis of anisoin to deoxyanisoin by tin and hydrochloric add, 40, 16 of arylsulfonyl chlorides to aryl disulfides by hydriodic add, 40, 81... 

A more general synthetic procedure to prepare aryltrifluoro-l -sulfanes. e.g. 4, is the fluorination of an aryl disulfide, e.g. 3, with silver(ll) fluoride, although the cost of the silver(II) fluoride precludes large-scale synthesis.80... 

Both oxidation and fluorodediazoniation with sodium nitrite and hydrogen fluoride/pyridine mixtures have been used advantageously in the synthesis of fluorinated aryl disulfides from aminobenzenethiols.98 In this case, too, the global yield is dependent on the hydrogen fluoride/ pyridine ratio (e.g., fluorodediazoniation yield = 65% with 20 wt % pyridine, 90% with 30 wt % pyridine, 93 % with 40 wt % pyridine and 10 % with 50 wt % pyridine for the formation of 4-fluorobenzenethiol).98... 

D. L. Trimm We have found no evidence of such attack on the alkyl and aryl disulfides produced in our study, even at a sodium hydroxide concentration of 5M. Such reactions would be expected to occur more easily, however, with substituted disulfides such as 3,3 -dithiodipropionic acid or 2,2 -dithiodiethylamine. 

Oxidative polymerization of aryl disulfides has been carried out under high dilution conditions for the preparation of cyclic arylene sulfides for synthesizing cyclic arylene sulfide polymers. The readily available diphenyl disulfide and dichloro disulfide with diphenyl sulfide, diphenyl ether, or p-xylene are useful monomers for the synthesis of the corresponding cyclic oligo(thio arylene)s. The reaction scheme is shown in Fig. 30 [101]. 

Sulfur compound VIII, a carboxytrimethylbenzene sulfonic acid, could have come from an aryl disulfide, a thiol or could be derived from the further oxidation of compound IX, a carboxytrimethyldibenzothiophene-1,1-dioxide. This latter possibility is indicated by the lower concentration of compound IX relative to compound VIII in the oxidation products of coals containing mineral matter. Once again the catalytic effect of the mineral component of coal is indicated. 

Though great advances have been made in the preparation of SF5 raw materials, more process research needs to be done before SF5-containing agrochemicals are commercially viable. The initial synthesis of pentafluorosulfur phenyl derivatives from silver difluoride and aryl disulfides resulted in low yields (Fig. 39) [178,179], Later, this procedure was improved by adjusting the temperature of the reaction, but it still relied on the use of expensive AgF2 [177,180],... 

There are two general routes to arylsulfonyl chlorides. The first involves the conversion of an already sulfur-substituted aromatic compound to the sulfonyl chloride. Thus arylsulfonic acids or their alkali metal salts yield sulfonyl chlorides by treatment with a variety of chlorinating agents such as phosphorus pentachloride, thionyl chloride, phosgene, and chlorosulfonic acid. Alternatively, substituted thiophenols or aryl disulfides can be oxidized by chlorine-water to the sulfonyl chloride.6... 

Aryl disulfides are oxidized to thiosulfmates using MTO-catalyzed H2O2. The use of an excess of H2O2 eventually affords the sulfonic acids through thiosulfi-... 

Zincke disulfide cleavage. Formation of sul-fenyl halides by three essentially similar methods involving the action of chlorine or bromine on aryl disulfides, thiophenols, or arylbenzyl sulfides. 

Included in the list of sulfides and mercaptans are diphenyl disulfide, dibenzyl disulfide, diamyl disulfide, bis(alkoxy aryl) disulfides, butyl mercaptan and thio-phenols, xylene thiols and other mercaptans, phenol sulfides and disulfides. ... 

Anderson patented the reclaiming of sulfur vulcanized rubber in the presence of oil, water vapor, and a mixture of aryl disulfides (diphenyl disulfide, dicresyl disulfide, and dixylyl disulfide) at elevated temperature and pressure. " ... 

These species were prepared by y-radiolysis of their corresponding dialkyl disulfides 187 at 77 K, treatment of the cyclic disulfides 188-191 or their corresponding dithiols with aluminum chloride in dichloromethane or sulfuric acid, by anodic oxidation of aryl disulfides 192,193a, and 194a, by bromine oxidation of 195 and iodine oxidation of 196. 

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