Sulfones from sulfinates

TABLE 1. Sulfones from sulfinic acids RS02H and acceptor-substituted olefins, acetylenes or quinones ... 

TABLE 3. Sulfones from sulfinates R1S02M and alkyl halides... 

In connection with route A, the formation of sulfones from sulfinates and a-haloketones on the one hand, and of isomeric enol sulfonates on the other (cf. Section III. A.4), should be pointed out. 

Sulfones from sulfinic acid esters S(0)0R SOgR... 

Sulfones from sulfinic acids and halides SO2H SOgR... 

Sodium hydrogen carbonate Sulfones from sulfinic acids s. 13, 7... 

TABLE 4. Sulfones from nucleophilic displacement of different weak leaving groups by sulfinates R1 SO2M... 

Aryl sulfones have been prepared from sulfinic acid salts, aryl iodides and Cul. Unactivated thiocyanation has been accomplished with charcoal supported copper(I) thiocyanate." ... 

TABLE 2. Sulfones from S-acylations of sulfinate anions RSOj... 

In contrast with the relatively facile thermal rearrangement of sulfinates to sulfones discussed in the preceding section, the reverse process is relatively, rarely encountered and is usually observed only at elevated temperatures. One of the first thermal sulfone to sulfinate isomerizations has been invoked by Fields and Meyerson to occur during the pyrolysis of dibenzothiophene S, S-dioxide (26) to dibenzofuran, through elimination of sulfur monoxide from the sultine intermediate 27 (equation 27). More recently, the flash vapor-phase pyrolysis of various 2,5-dialkyl and diaryl thiophene-S, S-dioxides has also been shown to involve SO extrusion and formation of the corresponding furans in good yields . 

Table 21-1. Halides prepared from alcohols via imidazole-V-carboxylates, -sulfonates and -sulfinates.

Rhodococcus sp. Strain T09 A Rhodococcus strain T09 was isolated by enrichment on media-containing BT. The desulfurization mechanism of this organism was reported to be similar to Gordonia sp. 213E due to the observation of similar intermediates however, the substrate specificity was different. The strain T09 could use 2-methyl, 3-methyl and 5-methyl BT apart from BT as sole source of sulfur for growth, but not 7-methyl or ethyl derivatives. Additionally, it could also use methyl thiobenzothiazole, marcaptobenzothiazole, as well as benzene sulfide, benzene sulfonate, biphenyl sulfinate, dimethyl sulfate, dimethyl sulfone, dimethyl sulfide, methane sulfonic acid, thiophene, and taurine as sole sulfur sources. However, it could not grow on DBT or DBT sulfone. 

Oxidation of sulfides and sulfoxides, as discussed above, and alkylation of sulfinate salts are the most common methods used to obtain sulfones for synthetic purposes [71, 109-113], A hydrogen peroxide-urea-phthalic anhydride system was recently proposed as a mild convenient reagent for the efficient preparation of sulfones from organic sulfides [114]. 

Arylsulfonyl chlorides are pivotal precursors for the preparation of many diverse functional types including sulfonate esters,8 amides,4 sulfones,9 sulfinic acids,10 and others.11 Furthermore, sulfonyl fluorides are best prepared from sulfonyl chlorides.12 The sulfonyl fluorides have many uses, among which is their utilization as active site probes of chymotrypsin and other esterases.13 The trifluoromethyl group also plays valuable roles in medicinal chemistry.14... 

To systematize the nomenclature of these processes, the eliminations of SO2 and SO3 are termed desulfination (from sulfinate) and desulfonation (from sulfonate), respectively. 

Aryl sulfones have been prepared from sulfinic acid salts, aryl iodides and Formation of thiocyanates from unactivated aryl halides has been accomplished with charcoal supported copper(l) thiocyanate. " The copper catalyzed reaction of Na02SMe and aryl iodides give the aryl methyl sulfone. " A similar synthesis of diaryl sulfones has been reported using a palladium catalyst. " ... 

Sulfonic acids and sulfonyl chlorides can also be prepared from sulfinic acids by oxidation with sodium permanganate (equation 590) [556] and chlorine in water (equation 591) [656], respectively. 

Sulfonic acid amides from sulfinic acids... 

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