During saponification of an ester with base, which two products are formed before any acid workup?

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Multiple Choice

During saponification of an ester with base, which two products are formed before any acid workup?

Saponification under basic conditions proceeds by hydroxide attacking the carbonyl of the ester, forming a tetrahedral intermediate that collapses to give a carboxylate salt and the alcohol corresponding to the ester’s alkoxy group. The base supplies the counterion, so you end up with a carboxylate salt (RCOO− with Na+ or K+) and an alcohol (R'OH) before any acid workup. Only after protonating the carboxylate during an acid workup do you obtain the carboxylic acid form of the product, while the alcohol remains unchanged. Therefore the two products formed prior to any acid workup are the carboxylate salt and the alcohol.

Saponification under basic conditions proceeds by hydroxide attacking the carbonyl of the ester, forming a tetrahedral intermediate that collapses to give a carboxylate salt and the alcohol corresponding to the ester’s alkoxy group. The base supplies the counterion, so you end up with a carboxylate salt (RCOO− with Na+ or K+) and an alcohol (R'OH) before any acid workup. Only after protonating the carboxylate during an acid workup do you obtain the carboxylic acid form of the product, while the alcohol remains unchanged. Therefore the two products formed prior to any acid workup are the carboxylate salt and the alcohol.

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