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This time I am interested in a specific type of acid anhydride, sulfonyl-carboxylates, i.e. compounds with the following molecular structure:

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where $\ce{R2}$ can be an organic substituents or hydrogen atoms. $\ce{R1}$ can be an organic substituent only.

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In addition to the procedures described by Ian Fang, these mixed anhydrides (with $\ce{R_1, R_2 \ne H}$) have been used to prepare symmetric anhydrides of carboxylic acid in solid state reactions. If that's interesting to anyone, I can look up the reference.

As far as the effect of water is concerned, I do remember a procedure where the mixed anhydrides in question were actually prepared in a biphasic system of water and dichloromethane in the presence of a phase-transfer catalyst.

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The mixed carboxylic anhydride, unless sterically hindered (the big sulfonyl helps) and electron rich, will be labile toward nucleophilic attack hydrolysis. Acetic anhydride usefully persists in cold (acidified) water. It goes exponentially as it exothermically hydrolyzes. Keep it cold. As above, use phase transfer for selective reactivity re the nylon rope trick.

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No, it hydrolyzes easily to a carboxylic acid ($\ce{R2COOH}$) and a sulfonic acid ($\ce{R1SO3H}$). $\ce{R1}$ should not be a hydrogen atom by the way.

It is common to use sulfonyl choride or sulfonyl anhydride to react with carboxylic acid to make mixed anhydride which then react with amine or alcohol (or alkoxide) to generate amide or ester. This reaction can be one pot but have to be dry otherwise hydrolysis will reduce the yield a lot. Have done it many times.

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    $\begingroup$ Could you add a reference to support this? $\endgroup$ – Philipp Sep 6 '13 at 17:55

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