Disulfides thiosulfonates

Sulfur compounds with divalent sulfur functionalities are much more prone to dioxirane oxidation on account of their higher nucleophilicity compared to the above-presented oxygen-type nucleophiles. Examples of this type of dioxirane oxidation abound in the literature. Such a case is the oxidation of thiols, which may be quite complex and afford a complex mixture of oxidation products, e.g. sulfinic acids, sulfonic acids, disulfides, thiosulfonates and aldehydes , and is, therefore, hardly useful in synthesis. Nevertheless, the oxidation of some 9i/-purine-6-thiols in the presence of an amine nucleophile produces n >( -nucleoside analogs in useful yields (equation 19). This reaction also displays the general chemoselectivity trend that divalent sulfur functionalities are more reactive than trivalent sp -hybridized nitrogen compounds P. 

A solution or suspension of 0.22 mol of the lithium or sodium alkynylide in 300 ml of liquid ammonia is prepared as described on p. 20. The disulfide, thiosulfonate or thiocyanate (0.20 mol, diluted with 50 ml of Et20, is added dropwise over 10 min with efficient stirring. In many cases a rather thick suspension is formed an additional volume of-100 ml of liquid... 

Yields of the sulfenylation products are generally excellent (except in the case of arylthiocyanates [58] which may undergo attack on the nitrile carbon) irrespective the fact if disulfides, thiosulfonates or thiocyanates are employed [59]. In some... 

Three substituted 5-phenyl unsymmetrical disulfides have been prepared, i, ii, and iii —compounds i and ii by reaction of a thiol with a sulfenyl halide, compound iii from a thiol and an aiyl thiosulfonate (ArS02SAr). The disulfides are cleaved by reduction (NaBH4) or by treatment with excess thiol (HSCH2CH2OH). 

Bloxham, D.P., and Cooper, C.K. (1982) Formation of a polymethylene bis(disulfide) inter-subunit crosslink between cys-281 residues in rabbit muscle glyceraldehyde-3-phosphate dehydrogenase using octamethylene bzs-(methane[35]thiosulfonate). Biochemistry 21, 1807. 

In soft cheeses, such as Brie, Camembert, and Limburger, the following sulfur compounds were implicated 3-(methylthio)propanol, MT, DMS, DMDS, DMTS, dimethyl tetrasulfide, methyl ethyl disulfide, diethyl disulfide, 2,4-dithiapentane, 3-methylthio-2,4-dithiapentane, methional, 2,4,5-trithiahex-ane, 1,1-fe-methylmercaptodisulfide, methyl thioacetate (=methanethiol acetate), benzothiazole, methylthiobenzothiazole, methyl ethyl sulfonate, methyl methane thiosulfonate, thiophene 2-aldehyde, and H2S.34 Many of these were only present in small amounts Limburger cheese was notable for 13.2% of DMDS, 0.5% of methyl thioacetate, and 0.8% of DMTS. 

In wet acetonitrile, the oxidation of diaryldisuUrdes [119] and dialkyl disulfides (Aik 7 f-Bu) [120] affords the corresponding aryl and alkylthiosulfonates in good synthetic yields (Eq. 15). Thus, the oxidation of a cyclic disulfide, dibenzo(c,e)-1,2-dithiin (1,1) does not affect the S—S bond and results in a corresponding thiosulfonate, dibenzo(c,e)-l,2-dithiin-l,l-dioxide(Scheme 27) [121]. Such oxidized products can form in wet acetonitrile as well as in a dry solvent, but in the latter case this is probably a result of disproportionation of the primarily... 

Cymerman, J., u. J.B. Willis Die Ultrarotspektren und die chemische Struktur einiger Disulfide, Disulfone und Thiosulfonate. J. chem. Soc. 1951, 1332. 

Alkali acetylides react very easily with disulfides, R SSR, thiocyanates, R SC=N, and thiosulfonates, R SS02R The reactions can be carried out in liquid ammonia as well as in organic solvents and generally give excellent yields of the acetylenic sulfides, RChCSR [2,105]. Although sulfenyl halides seem suitable reagents for the introduction of alkylthio- or arylthio groups, they are seldom used for this reaction, because of their sensitivity and the... 

Reaction of Metallated Acetylenes with Disulfides or Thiocyanates or Thiosulfonates in Liquid Arramnia... 

The most important flavour compound in raw onions is thiopropanal-S-ox-ide, the lachrymatory factor [145,146]. Other important flavour compounds are 3,4-dimethyl-2,5-dioxo-2,5-dihydrothiophene and alkyl alkane thiosulfonates such as propyl methanethiosulfonate and propyl propanethiosulfonate with a distinct odour of freshly cut onions [35, 36, 147]. Various thiosulfinates that have a sharp and pungent odour may also contribute to the flavour of onions. These compounds, however, are rapidly decomposed to a mixture of alkyl and alkenyl monosulfides, disulfides and trisulfides (Scheme 7.3) of which dipropyl disulfide, methyl ( )-propenyl disulfide, propyl ( )-propenyl disulfide, dipropyl trisulfide and methyl propyl trisulfide are the most important contributors to the aroma of raw and cooked onions (Table 7.5, Fig. 7.6) [148-150]. Recently, 3-mercapto-2-methylpentan-l-ol was identified in raw and cooked onions eliciting intense meat broth, sweaty, onion and leek-like odours [142, 151]. 

The following routes to unsymmetrical disulfides and symmetrical trisulfides use silyl sulfides and thiosulfinates [41.42]. Thiosulfonates react similarly. 

The treatment of diaryl disulfides with BTIB in dichloromethane leads to the production of S-aryl thiosulfonic esters 7 (Scheme 4) [18]. When such reactions are conducted in an alcoholic medium, arenesulfinic esters 8 are obtained [19]. Similar conversions of arenethiols to 7 or 8 with BTIB can also be effected [18,19]. 

Disulfides, diselenides, and ditellurides can be oxidized by hypervalent iodine compounds quite easily. Depending on the reaction conditions disulfides can be oxidized to sulfinic esters [59] or thiosulfonic S-esters [60,61]. Diselenides can be transformed into selenosulfonates [62]. Arenetellurinic mixed anhydrides are mild oxidants and can be obtained by oxidation of the corresponding ditellurides as shown in Scheme 9 [63]. Recently it was shown that a thioacetal based linker for solid-phase synthesis can be cleaved oxidatively using [bis(trifluoro-acetoxy)iodo]benzene 4 [64]. 

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. 

The bulbous vegetables of the Allium group all have a characteristic aroma attributed to thiosulfonates and disulfides. 

Examples of catalytic systems include the following ones. [ReOCl3(PPh3)2] catalyzes the oxidation (with sulfoxides) of thiols to disulfides, of sulfides to sulfoxides, of acyclic disulfides to thiosulfonates (RSO2SR), of cychc disulfides... 

Lower yields are observed when R is a secondary group, and no thiosulfonate is formed with R = r-Bu. Although thiosulfinates, RSOSR, are intermediate products, they are not oxidized under the electrolysis conditions. It was shown that thiosulfinates are transformed into thiosulfonates in the presence of disulfides being oxidized, presumably involving an intermediate species electrogenerated from the disulfide [38b]. Diaryl disulfides also lead to thiosulfonates in good yields when oxidized under similar conditions [39]. The disulfoxide, RSOSOR, supposedly obtained in the anodic oxidation of dibenzyl disulfide in a HOAc/HCl solution at a Pt anode [40], is probably also a thiosulfonate. 

The reduction of sulfonyl chlorides may lead to sulfinates [265-267], thiosulfonates [267], disulfides, and mercaptans depending on the conditions in the presence of alkylating agents [266], sulfones or sulfides are among the products. 

Use of thiirane 1,1-dioxide affords a useful synthesis of ethanesulfinates with the following functions in the 2-position thiol, disulfide, trisulfide, thiosulfate, thiosulfonate, and phos-phorthioate. Reaction of episulfone (83) with sodium p-toluenethiolate gives the sulfinate (84), which can be converted to the sulfone (85) (Scheme 35). Similarly, (83) is converted to the benzyl counterpart (86), which is desired for possible debenzylation to the thiol since the salt (86) is difficult to purify, it is converted to the ethyl ester (87) <86JOC5235>. 

---