Alkylsulfonic acid aryl esters

Beside all pollutants described above, several organic contaminants identified and monitored in rivers and groundwater remain undiscussed, because they were either only rarely detected so far or of minor environmental interest in terms of ecotoxicological aspects. Examples include e.g. N-methylpyrrolidinone, dinapthylsulfones, polychlorinated n-alkanes, alkylsulfonic acid aryl esters, hexabromobenzene and X-ray contrast media (Watanabe et al. 1986 Franke et al. 1998a Temes and Hirsch 2000 Nicholls et al. 2001 Eleadley et al. 2001 Schwarzbauer and Franke 2003b). 

In addition numerous compounds were detected which may serve as potential anthropogenic markers with respect to their source specifity and environmental persistence. Plasticizers (alkylsulfonic acid aryl esters, tributyl and tricresyl phosphates), synthetic fragrances (galaxolide, tonalide, 4-oxoisophorone) and additives of personal care products (4-methoxycinnamic acid 2-ethylhexyl ester, benzyl benzoate, dibenzyl ether, benzophenone) occurred due to sewage treatment plant effluents and reflect therefore an anthropogenic contamination of the particulate riverine matter, even in marine systems. 

Sultones are the internal esters of hydroxy sulfonic acids and are the sulfur analogs of lactones. Sultones are demanded scaffolds in medicinal chemistry research. Biological studies on sultones are mainly concerned with their toxicological, skin sensitization, and antiviral activities [20]. Sultones are synthetically useful heterocycles which can react with a variety of compounds to introduce the alkylsulfonic acid function and therefore used as sulfoalkylating agents [21]. There have been several new developments for the synthesis of sultones which have also been applied in the total synthesis of natural products. In recent years, the palladium-catalyzed direct arylation of several aromatics via a C-H bond activation using aryl halides has led to successes. An intramolecular version of this reaction has allowed the synthesis of several biaryls via the formation of five- to seven-membered rings. Thus, the sultones should be synthesized by C-H activation via two pathways (Scheme 4.14). 

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