Alkyl disulfides

Organosulfur Adsorbates on Metal and Semiconductor Surfaces. Sulfur compounds (qv) and selenium compounds (qv) have a strong affinity for transition metal surfaces (206—211). The number of reported surface-active organosulfur compounds that form monolayers on gold includes di- -alkyl sulfide (212,213), di- -alkyl disulfides (108), thiophenols (214,215), mercaptopyridines (216), mercaptoanilines (217), thiophenes (217), cysteines (218,219), xanthates (220), thiocarbaminates (220), thiocarbamates (221), thioureas (222), mercaptoimidazoles (223—225), and alkaneselenoles (226) (Fig. 11). However, the most studied, and probably most understood, SAM is that of alkanethiolates on Au(lll) surfaces. 

Chemisorption of alkanethiols as well as of di- -alkyl disulfides on clean gold gives indistinguishable monolayers (251) probably forming the Au(l) thiolate species. A simple oxidative addition of the S—S bond to the gold surface is possibly the mechanism in the formation of SAMs from disulfides ... 

When thionyl chloride is used, diaryl sulfoxides are usually the main products. Unsymmetrical diaryl sulfides can be obtained by treatment of an aromatic compound with an aryl sulfenyl chloride (ArSCl) in the presence of a trace amount of iron powder.Aromatic amines and phenols can be alkylthiolated (giving mostly ortho product) by treatment with an alkyl disulfide and a Lewis acid catalyst. With certain substrates (primary amines with a chloro group, or a group not replaceable by chloro, in the para position), treatment with S2CI2 and NaOH gives thiophenolate salts ... 

Alkyl-l,3-cyclopentanediones, 58, 82 Alkyl 2,2-dimethylpropanethioate, 58, 146 Alkyl disulfides, 58, 142... 

During the last two decades, Bentrude et al. [70] has shown that phosphoranyl radicals exhibiting very slow a- and P-fragmentations react with alkyl disulfides via Sh2 homolytic substitution (Scheme 35) [70b]. The reactivity of phosphoranyl radicals in these Sh2 reactions depends strongly on the substituents attached to the phosphorus atom and on the structure of the disulfides [70c]. 

Scheme 35 Sh2 reactions of phosphoranyl radicals with alkyl disulfides...

Thiols are known to be excellent hgands for the stabilization of gold and platinum nanoparticles. In this respect, we did not observe any Iluxional behavior [31,52] in solution NMR experiments for thiols coordinated to the surface of noble metal particles (Fig. 8). However, in the case of rutheniiun, we foimd the slow catalytic formation of alkyl disulfides [31]. After exclud-... 

The carbonyl undergoes a variety of complex formation reactions, involving partial or total replacement of CO groups with other donors. Many reactions have synthetic applications. Such donors include pyridine (py), diglyme, toluene, aniline, cycloheptatriene, alkyl disulfide and metal cyctopentadiene. A few examples are given below ... 

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

Alkylation, enolates, 56, 52 ALKYLATIVE COUPLING, 55, 127 2-Alkyl-l,3-cyclopentanediones, 58, 82 Alkyl 2,2-dimethylpropanethioate, 58, 146 Alkyl disulfides, 58, 142 Alkyl fluoride, 58,77 Alkyl halide, 58, 145... 

Photooxidation finds occasional use in synthesis. Compounds such as XXX are formed by the oxidation of sterically hindered bis (sec-alkyl)-, and bis(organic peroxy acids.39 Compound XXXI is produced in pyridine solution of thiourea236 in the presence of photosensitizer and oxygen under the influence of ultraviolet light. 

An alternative synthetic route to platinum(II) thiolates is by the oxidative addition of the S—S bond to platinum(O). When the sulfur atom has phenyl or electron-withdrawing substituents such as CF3, this reaction is a useful one to synthesize the thiolato platinum(II) complexes (equation 503).1703-1705 Simple alkyl disulfides such as Me2S2 and Et2S2 do not form stable dithiolato complexes of platinum(II) by S—S addition to Pt(PPh3)3, but if chelation can occur, chelate-assisted oxidative addition can induce S—S cleavage (equation 504).30 An unusual cyclic thiolato complex is obtained by the decarbonylative cleavage of a C—S bond (equation 505).1707... 

When we reacted hexafluoro-2-butyne and methyl disulfide, the reaction proceeded readily in good yield to form the isomeric 1 1 adducts [i.e., cis- and trans-2,3-bis(methylthio)hexafluoro-2-butene in equal mole ratio], but the formation of the methylthio adducts with hexafluorobutadiene was difficult (9). This agrees with the previous alkyl disulfide and the terminal olefinic bond reaction (Eq. 2, where k, /k2 [RSSR] is relatively large) proceeding to a very poor yield of the adduct (10) ... 

Bass, S.W. and Evans, S.A., Jr., Carbon-13 nuclear magnetic resonance spectral properties of alkyl disulfides, thiosulfinates, and thiosulfonates, J. Org. Chem., 45, 710, 1980. 

As an example, thiolacetic acid was photoadded in high yield to butenyl aromatics in the multigram scale synthesis of compounds 35 (Scheme 3.23) [56], These products were, in turn, starting materials for the preparation of aryl-alkyl disulfides that were employed as protective agents for gold nanoparticles due to a passivation process. 

Methionol (= 3-(Methylthio)-propanol) (thioether alcohol) 4-Methoxy-2-methyl-2-butanethiol (alkyl thiol) Methyl allyl disulfide (alkyl disulfide)... 

Dimethyl disulfide (alkyl disulfide) Scent of bat-pollinated flowers Nectarivorous bat (Glossophaga soricina) attractant... 

Sodium thiosulfate reacts with alkyl halides to form salts of the type RSSOjNa (Bunte salts). Alkyl disulfides may be obtained from these salts by pyrolysis or reaction with iodine or hydrogen peroxide. The yields range from 47% to 6S>%. Cyano and carboxyl groups do not interfere. Benzoylation of sodium thiosulfate produces benzoyl disulfide in 58% yield. ... 

Oxidation ofdisu des. A simple alkyl disulfide is oxidized by the reagent at —78°... 

---