Polysulfur oxides

A number of suboxides of sulfur have been reported, but in general their composition has not been clearly established. Polysulfur oxides of formula Ss- 10O2 are formed by reaction of hydrogen sulfide and sulfur dioxide. Also, when sulfur is burned with oxygen in very limited supply disulfur monoxide, S20 is formed. This has the structnie... 

Polysulfur oxides are formed by the polymerization and partial disproportionation of S2039 or by the oxidation of S8.46 The complexes [(S80)SbCl5] and S1202-2SbCl5 3CS2 are known the ligand is O-bonded.46... 

Sulfur Monoxide Disulfur Monoxide Disulfur Dioxide Polysulfur Oxides... 

Disulfuroxide (S=S 3) and disulfurdioxide (0=S=S=0) are unstable, and they polymerize to give polysulfur oxides. In disulfuroxide, the S=S bond is weaker and more polarized than the S=0 bond . Disulfur oxide is conveniently generated in the thermolysis of 4,5-diphenyl-3,6-dihydro-1,2-dithiin-l-oxide 2. ... 

Although these equations held true for some strains of bacteria under some growth conditions, they did not help explain the commonly observed quantitative conversion of both sulfur atoms of thiosulfate to sulfate, rather than the liberation of the sulfane-sulfur mainly as elemental sulfur. During the 1960s, cyclic reactions of polythionates and other polysulfur compounds continued to be postulated as mechanisms for thiosulfate and polythionate metabolism (Trudinger 1967), but none of these was supported at the time by strong biochemical evidence. The time was opportune for a new approach to the problem of thiosulfate oxidation in thiobacilli. 

The oxidation of cyclo-Sg with strong oxidising agents, e.g. AsFs, produces polysulfur cations, which are isolated as lattice-stabilised salts of dications, e.g. 

More than ten oxides of sulfur are known, and the most important industrially are SO2 and SO3. The six homocyclic polysulfur monoxides S 0 (5 < n < 10) are prepared by oxidizing the appropriate cyclo-S with trifluoroperoxoacetic... 

An unusual transformation occurred when triethylamine reacted with disulfur dichloride and 1,4-diazabicy-clo[2.2.2]octane (DABCO) to form heptathiocane 103 (mp 72-73 °C) and thienopentathiepine 104 (Scheme 7) <20030L1939>. The proposed mechanism involved the adduct 102 and oxidation of the intermediate complex 105, followed by the formation of enamines 106 and 107. The intermediate 106 outlined a pathway to the extended polysulfur chain, such as in 107, which cyclized into heptathiocane 103. Incorporation of only one carbon into the heterocyclic ring from the ethyl group rather than both was presumably controlled by the reactivity of the enamine 107. For the mechanism of formation of thienopentathiepine 104, Chapter 13.17, CHEC-3 should be consulted. The rare heptathiocane ring stmcture was proved by X-ray crystallography (Section 14.09.3.3). 

Of the many reactions known for polysulfanes, only the following types will be dealt with since they are of general importance for inorganic and organic polysulfur compounds interconversion and sulfur transfer reactions, nucleophilic displacement reactions, and oxidation reactions with conservation of chain length. 

The sulfite (SOf ) anion can undergo reoxidation by oxygen closer to the sediment surface to produce polysulfur anions or even sulfate. Elemental sulfur may be found in marine sediments as a product of the oxidation of iron sulfides (Schippers and Jorgensen, 2001). The incorporation of pyrite and organosulfides, formed as a by-product of sulfate reduction in marine sediments, is a major sink for seawater S04. Over geological time we have seen that this is an important process in controlling the concentrations of seawater sulfate. 

At least thirteen proven oxides of sulfur are known to exist though this profusion should not obscure the fact that SO2 and SO3 remain by far the most stable and unquestionably the most important economically. The six homocyclic polysulfur monoxides S 0(5 < n <... 

Elemental sulfur may be oxidized to a variety of polysulfur cations. Thus, oxidation of Sg in liquid SOj with AsFj or SbFj leads to among other species ... 

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