Reaction with disulfides

White phosphorus is reported to react with dialkyl disulfides at 200 °C (2 h) to give the corresponding trithiophosphites, e.g., (BuS)3P (70% yield) This reaction may also be carried out in high boiling solvents such as hydrocarbons 

CH3CH2CH=CH2 + Pr + AICI3 35 2 olefinic polymer containing phosphorus 69) 

Aromatic hydrocarbons liaving aliphatic side chaines + Pw 

The reaction of white phosphorus with dimethyldisulfide, initiated by irradiation, is composed of two steps a) formation of red phosphorus with participation of the solvent b) formation of ( 1138)3 from red phosphorus. The radiation chemical yields are of the order of several 100 molecules/100 eV at room temperature which indicates a radical chain reaction  

At low dose rate red phosphorus lias the composition (CH3SP2)jj While commercial red phosphorus does not react with Me2S2 with irradiation, red phosphorus, obtained from wliite phosphorus by irradiation in cyclohexane and having the composition (CgHj 1 P4.86)n reacts with Me2S2 when irradiated with °Co y-rays to yield ( 1138)3 and, P(8 H3)2 in the ratio 3.6 1 

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Gold(I) thiolates also undergo reactions with disulfides. An example is 2,2-dithio-bis(2-nitrobenzoic acid) (ESSE) used as a kinetic probe of sulfhydryl reactivity in metallothioneins [39-42]. ESSE is readily attacked by metal-bound thiolates. The reaction with the open chain form of AuSTm seems to occur in two stages. The first attack involves the terminal sulfides and the second attack involves the bridging thiolates [19] ... 

Another example for gem-functionalization is demonstrated in the reaction with disulfides. The tandem sulfenylation and carbonylation to 1-alkylthiocy-clopropanecarbothioates 168 are realized, indicating that disulfides can serve both as nucleophiles and electrophiles [81], (Scheme 63)... 

Toxicity of gold may in part be due to reactions with disulfide groups in proteins according to equations (36) and (37). 276... 

The same team studied also Art-butyl-substituted thiiranium and thiirenium ions in reactions with disulfides, which led to the formation of thietanium and thietium ions, respectively. However, this paper only reported upon the kinetics of this... 

The same alkyl thiocarbamates 95 can be prepared in 35-72% yield by reaction with disulfides and with carbon disulfide followed by alkylation with alkyl halides100. When carbonyl sulfide was used as electrophile, lithium /V,/V-dialkyldioxamates were formed, which after reaction with benzyl bromide gave thiooxamates 96 in 37-56% yield100. 

A general method for the preparation of trifluoromethyl sulfides involves the utilization of trimethyl(trifluoromethyl)silane ("Ruppert s Reagent") in a reaction with disulfides 32. ... 

Reaction of [MoS4] with tetraalkythiuramdisulfides afforded [Mo(S2)(S2CNR2)3], while reaction with disulfides, RSSR, gave dinuclear [M0282( 1-8)2(82)2] ... 

This is merely a formulation, however, and any plausible reaction mechanism seems to involve precisely the same type of difficulties as are associated with the simpler formulation (IV). For example, Milligan and Swan (1961) obtained some evidence that Bunte salts can undergo an exchange reaction with disulfide bonds. They suggest (Milligan and Swan, 1962) that such an exchange mechanism can lead to the reactions. 

Alkylthiylation of triquinphosphoranes has been achieved by reaction with disulfides either in the dark or under UV irradiation. Thus (89ab) on reaction with (90) in toluene gave (9lab) and in the case of (91b) the NMR data were consistent with either an enantiopure sp configuration or with diastereomeric trigonal bipyramids in fast equilibrium. The major product of the reaction of... 

Chrisman, P.A. Pitteri, S.J. Hogan, J.M. McLuckey, S.A. SOj electron transfer ion/ion reactions with disulfide linked polypeptide ions. J. Am. Soc. Mass Spectrom. 2005,16, 1020-1030. 

Benzylpenicillenic acid, which forms readily from benzylpeniciUin in aqueous solution, is unstable and is thought to be allergenic, particularly in contact skin allergy, after direct reaction with disulfides and cysteine sulfhydryl groups (Fig. 5.6). Immunization of laboratory animals with penicil-lenate-protein and penicilloyl-protein conjugates... 

Displacement reactions with disulfides are a second major pathway to generate thiyl radicals. Formally, this constitutes a one-electron reduction of the disulfide. Homolytic sulfur-sulfur bond breakage by carbon-centered or phosphite radicals, for example, has been shown to lead to sulfides with mixed substitution and thiophosphates, respectively [17, 18], reactions (5) and (6) ... 

Whether this can be rationalized directly by reaction (11) yielding sulfinyl radicals besides thiols, or involves a more complex reaction scheme still remains an open question. There seems little doubt about the production of the sulfinyl radicals, as they could unambiguously be identified in complementary ESR experiments in which the hydroxyl radicals were generated via Fenton chemistry in acid solutions [23]. One mechanistic suggestion put forward [22] discusses the intermediacy of an OH-adduct radical, R-S (OH)-S-R which in basic solution may suffer OH attack to yield RS together with the hydrated form of the sulfinyl radical, RS(OH)2 . In acid solution, on the other hand, a secondary oxidation of the sulfenic acid (formed in reaction (10)) by disulfide radical cations (also formed upon OH reaction with disulfides, vide infra), that is reaction (12) has been brought into the discussion. 

In organic chemistry, particularly synthesis, all these displacement reactions with disulfides have for the most part served as a means of obtaining the respective molecular products, and the focus has been much less on the study of the thiyl free radicals per se. Radiation chemical investigations on these processes have, however, revealed many interesting details of the respective mechanisms and, as such, supported a number of suggestions and conclusions made in... 

The DTT dithieno[2,3- 3, 2 -J]thiophene (244) was prepared as early as 1958, starting from thiophene itself. 2,5-Dilithiation then reaction with disulfide (310) gave (311), which underwent a double ring closure promoted by PPA to furnish 244 (Scheme 76) [126]. 

Sulfenamides can be synthesized by a metal-assisted reaction with disulfides and amines (eq 13). Conjugated dienols can be synthesized in a highly chemo-, regio-, and stereoselective manner from vinylic halides and allylic alcohols (eq 14). Silver acetate (or silver carbonate) and a catalytic amount of palladium(II) acetate in DMF are the preferred conditions. The reaction is very attractive because it requires only one functionalized alkene reactant and the addition of the vinylic group only occurs at the terminal carbon of the aUyUc alcohol. 4... 

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