Arenesulfonic aryl esters

More direct evidence against 147 (though still not conclusive) was found in an experiment involving acidic and basic hydrolysis of aryl arenesulfonates, where it has been shown by the use of lsO that an intermediate like 147 is not reversibly formed, since ester recovered when the reaction was stopped before completion contained no 180 when the hydrolysis was carried out in the presence of labeled water.1724... 

In general it is not possible to perform arylations by aryl arenesulfonates, but some nitroaryl esters form exceptions, as was found by Ullmann.853 854... 

Primary alkyl arenesulfonates and halides react with aryl boronate esters in the presence of a Cul catalyst and f-BuOLi in A,A-dimethylformamide (DMF) to give the cross-coupling product in yields between 50 and 87%. Yields decrease from X = I to Cl and from tosylate (OTs) to mesylate (OMs). This reaction is thought to occur between the substrate and the organocopper intermediate formed from the borate ester,... 

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