Sulfonyl compounds

In recent years the number of relatively simple sulfonyl molecules for which geometry has been determined in the vapor phase has increased considerably. The additional data are listed in Table 3. At this point there are a total of 40 geometries for sulfonyl compounds that have been determined in the vapour phase all of them are indicated in the r sin a versus r cos plot in Figure 19. While this number corresponds to a much larger sample of data than that considered previously, unfortunately the accuracy and the experimental sources are much more variable than for the smaller sample therefore, no rigorous conclusions should be drawn on the basis of these data. It is remarkable, however, that the mean O O nonbonded distance of the 40 geometries is the same, 2.484 A, as in the smaller... 

Sulfinyl chlorides may be prepared from the corresponding thiols or disulfides by oxidative reactions rather than by reductions of sulfonyl compounds. A recent example, which improves the earlier procedure of Douglass, is given by equation (3)50. The chemistry of sulfinic acids and their derivatives has been reviewed51 52,53. 

In principle, sulfonyl compounds bearing highly-electron-accepting substituents are able to transfer the sulfonyl group as an electrophile. Thus, the exchange of aryl substituents in methyl aryl sulfones under catalysis of trifluoromethanesulfonic acid takes place258 (equation 46). This reaction represents a further example for the reversibility of Friedel-Crafts reactions. 

In this chapter it is clearly impossible to do more than sample the extensive literature on the carbon acidity of sulfinyl and sulfonyl compounds, as it illuminates the electronic effects of these groups, particularly in connection with linear free-energy relationships. There are three main areas to cover first, as already indicated, equilibrium acidities (pKa values) second, the kinetics of ionization, usually studied through hydrogen isotopic exchange and finally, the kinetics of other reactions proceeding via carbanionic intermediates. 

TABLE 16. Base-catalyzed H/D exchange reactions of sulfonyl compounds 70-73... 

Some representative data on base-catalyzed H/D exchange reactions of several optically active sulfonyl compounds 70-73 are listed in Table 16. In all these reactions, 10. 

Tetrahedral Intermediates Derived from Carbonyl Compounds, Pentacoordinate Intermediates Derived from Phosphoryl and Sulfonyl Compounds, and Concerted Paths Which Avoid Them... 

Enamine nucleophiles react readily with soft conjugated electrophiles, such as a, 3-unsaturated carbonyl, nitro, and sulfonyl compounds [20-22], Both aldehydes and ketones can be used as donors (Schemes 27 and 28). These Michael-type reactions are highly useful for the construction of carbon skeletons and often the yields are very high. The problem, however, is the enantioselectivity of the process. Unlike the aldol and Mannich reactions, where even simple proline catalyst can effectively direct the addition to the C = O or C = N bond by its carboxylic acid moiety, in conjugate additions the charge develops further away from the catalyst (Scheme 26) ... 

The diimines (229) differ considerably in thermal stability. The sulfonyl compounds (226) and (229a) are stable crystalline compounds which rearrange at elevated temperatures. The acyl derivatives (229b and c) and the dianion formed by demesylation of (226) undergo retrocyclization below -15 °C at a rate equal to or faster than loss of N2O from N- nitroso intermediates. 

Studying the formylation of alkylbenzenes in HS03F-SbF5, Tanaka et al436 have observed both formylation and sulfonation. However, in the presence of HSO3F, that is at low acidity level, only sulfonyl compounds were obtained [Eq. (5.167)], whereas increasing acidity (with added SbF5) resulted in the formation of products of formylation. 

The most important feature of the spectra is the large blue shift of the sulfones vs the nitro derivatives, i.e., 53 nm (3098 cm 1) for the stilbene, and 30 nm (1400 cm 1) for the azobenzene derivatives, in toluene). These large blue shifts suggest that sulfonyl compounds are more transparent in the visible region than their nitro... 

Whereas the sulfone group has been demonstrated to produce lower molecular hyperpolarizabilities than those of nitro groups, the difference becomes less as the degree of conjugation is increased. One would therefore expect that this difference will decrease further in more highly conjugated systems. The increased visible spectrum transparency and the synthetic flexibility may make these sulfonyl compounds important for some applications. 

Naphthalene (C qHq) is a condensed aromatic compound obtained from coal tar. It has a relatively low melting point (80.2°C b.p. 217.9 )i sublimes readily on warming, and exerts sufficient vapor pressure at room temperature to be readily detectable by its characteristic odor. It is a chemical intermediate or feedstock in the synthesis of a large number of derivatives (e.g., phthalic, anthranilic, hydroxy-, amino- and sulfonyl-), compounds used in the production of the coal tar dyes. 

The lipophilicities of ( )-3-benzylidenethiochroman 4-one 251 and its 1-oxide, 1,1-dioxide, and the 2-phenyl derivative have been determined by reverse phase HPLC and a good linear correlation with calculated values is observed. The stronger polarizability of the sulfinyl and sulfonyl compounds results in decreased retention time, but the thioflavanone has the greatest lipophilicity <2005JCH(819)283>. 

The chloro sulfonyl compound is converted to a sulfonamide by ammoniation. 

The reduction of sulfoxides and A -oxides has been reported to occur in a number of mammalian systems. It appears that liver enzymes reduce sulfoxide or sulfonyl compounds to thioether or sulfides under anaerobic conditions (Figure 10.9E). iV-Oxides have also been reported to be reduced by a bacterial reductase ... 

Triazolinones are obtained by the alkaline hydrolysis of methyl-sulfinyl or -sulfonyl compounds (118 Scheme 39) (73JMC312). Hydrolysis of alkoxytriazoles to triazolinones (68AP911) is of practical importance, but the ready conversion of heteroaromatic triazoles to triazolinones may be complicated by the non-hydrolytic rearrangement of alkoxytriazoles such as (119) to (120) in Scheme 40 (esjpRies). 

Sulfinyl and sulfonyl compounds react with BI3 [221 and BI3 NEtaPh [23] to afford disulfides (Eq. 11). 

The transformation of an active CH compound into the corresponding diazo derivative with -toluenesulfonyl azide has been designated a diazo transfer reaction and possesses a variety of preparative uses. The method has been useful for the syntheses of diazo derivatives of cyclopentadiene, 1,3-dicar-bonyl compounds, 1,3-disulfonyl compounds,1,3-keto-sulfonyl compounds, ketones, " carboxylic acid esters, and /3-keto imines. Further reaction of these diazo intermediates can lead to azo compounds,"- " 1,2,3-triazoles, and pyrazolinones. ... 

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