1 - ethyl arenesulfonates

Nucleophilic substitution reactions of l-(trimethylsilyl)ethyl arenesulfonates, 3, with anilines in MeCN at 65.0 °C was found to proceed by an Sw2 mechanism56. The pxz... 

Effectiveness as a base [1, 1268, after line 2]. In studying the acetolysis of ethyl arenesulfonates, Bartlett and co-workers2311 wished to add a base sufficiently strong to convert the sulfonic acid produced into an inert sulfonate salt but one that is non-nucleophilic and not able to effect direct displacement (which can happen with sodium or potassium acetate). For this purpose they used urea successfully. 

Esterification of sulfonic acids.1 Sulfonic acids are converted into methyl or ethyl esters on reaction with trimethyl or triethyl orthoformate. Yields are >80% in esterification of arenesulfonic acids, but are somewhat lower in the reaction of alkanesulfonic acids because of volatility of the products. 

The rates of solvolysis in ethanol, formic acid, and acetic acid of l-(p-methoxyphenyl)ethyl toluene-p-sulfonate (65) are approximately the same as those of its para isomer (66). Because of the lack of product analyses and therefore quantitative knowledge of the importance of aryl participation " and the pathway,it is not possible to determine the extent of o-MeO-5 participation. However, o-MeO-6 participation occurs extensively in the acetolysis and formolysis of the analogous 3-(o-methoxyphenyl)-l-propyl p-bromobenzenesulfonate (73) and 3-(o-methoxyphenyl)-3-methyl-l-butyl toluene-p-sulfonate (74) (see Table 6). Any competing aryl participation would be Ari-4 participation and, as shown by the reaction rates for the para isomers, is unimportant. The reaction products (Table 6) contain large amounts of the pyran derivatives (75) and (76) and of the methyl arenesulfonates, and the reactions may therefore be formulated as shown in... 

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