Sulfides/sulfoxides

Radicofunctional nomenclature finds some use in naming ethers, sulfides, sulfoxides, sulfones, selenium analogs of the preceding three sulfur compounds, and azides. 

The 13C NMR data for representative three-membered sulfones and sulfoxides are given in Table 5. The chemical shifts of the sp3-hybridized a-carbon in the parent thiirane70 and the five-membered ring86 sulfide, sulfoxide and sulfone are 18.1, 31.7, 54.3 and 51.1, respectively, whereas those of cyclopropenone, diphenylcyclopropenone and dimethylcyclopropenone are 169.087, 148.788 and 157.9, respectively. 

Oxidation of the sulfur in thiiranes (20) to the corresponding sulfoxides (i.e. 16) and further oxidation to the sulfones (17) is formally analogous to the sequence sulfides - sulfoxides -> sulfones in the acyclic or large ring series (equation 34). 

A final, rather different example which fits in appropriately here, in that it involves hydrogen exchange, is the measurement of equilibrium and rate constants for the base-catalyzed isomerization of unsaturated sulfides, sulfoxides and sulfones193 ... 

Lei B, S-C Tu (1996) Gene overexpression, purification, and identification of a desulfurization enzyme from Rhodococcus sp. strain IGTS8 as a sulfide/sulfoxide monooxygenase. J Bacteriol 178 5699-5705. 

Ohta and coworkers used a bacterium, Corynebacterium equi IFO 3730, rather than a fungus, to oxidize eight alkyl phenyl and p-tolyl sulfides to their respective sulfoxides (119, 120) of configuration R. Virtually all of the sulfur compounds were accounted for as the sum of uncreacted sulfide, sulfoxide and sulfone. The enantiomeric purities of the sulfoxides obtained were quite good and are shown below in parentheses. The formation of the allyl sulfoxides in high optical purity is noteworthy. The authors believe that the sulfoxides were formed by enantioselective oxidation of the sulfides rather than by enantioselective oxidation of racemic sulfoxides, since the yield of sulfoxides was greater than 50% in five of the ten oxidations reported (see also Reference 34). 

Oxidation of thiirane and thiirene oxides to the dioxides is the best method to obtain the sulfones. Indeed, in the acyclic, or large-ring systems, the sequence sulfide- sulfoxide - sulfone is by far the easiest method to prepare sulfoxides and sulfones. The situation is different in the three-membered ring series Thus, oxidation of thiiranes to the oxides by either perbenzoic acid or m-chloroperbenzoic acid under mild conditions affords the corresponding thiirane sulfoxides in almost quantitative yield - . However, further... 

Caron, G., Gaillard, P., Carrupt, P. A., Testa, B. Lipophilicity behavior of model and medicinal compounds containing a sulfide, sulfoxide, or sulfone moiety. 

Lei, B. F., and Tu, S. C., Gene Overexpression, Purification, and Identification of a Desulfurization Enzyme From Rhodococcus Sp Strain IGTS8 as a Sulfide/Sulfoxide Monooxygenase. Journal of Bacteriology, 1996. 178(19) pp. 5699-5705. 

Certain metal-carbene complexes such as [(CH3 )4N][(CO)5WCOPh] and (CO)5WC(OC2H5)Ph in combination with PR3, sulfides, sulfoxides, quinones. or /V-chlorosuccinimide, together with a TiCl4 cocatalyst, were also effective catalysts, at monomer/W molar ratios of up to 5000/1 (104). 

The iridium-catalyzed hydroboration of heteroatom-containing substrates (vinyl sulfides, sulfoxides, sulfones and sulfonates) was examined by Westcottand Baker [43]. These authors observed the selechve formation of the linear boronate ester... 

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