Esters, carboxylic acid saponification equivalent

The hydrolysis is generally not carried out at pH 7 but is either acid-catalyzed or base-mediated (i.e., as a so-called saponification). Base-catalyzed ester hydrolyses do not exist The carboxylic acid produced protonates a full equivalent of base and thus consumes it. 

In the second step, the two methyl ester moieties are hydrolyzed under basic conditions to the corresponding carboxylic acids. Whereas typical saponification methods (2 N KOH, reflux, 48 h) failed, the hydrolysis proceeded smoothly with "anhydrous hydroxide".This reagent - relatively unsolvated hydroxide - was generated via the reaction of two equivalents of potassium /er/-butoxide with one equivalent of water. 

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