Ester hydrolysis (saponification) with NaOH followed by acid workup yields what species initially?

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Multiple Choice

Ester hydrolysis (saponification) with NaOH followed by acid workup yields what species initially?

Base-promoted ester hydrolysis (saponification) proceeds when hydroxide attacks the carbonyl carbon, forming a tetrahedral intermediate. The OR' group leaves as RO-, which is quickly protonated by water to ROH. The acyl portion becomes a carboxylate (RCOO-). In the presence of NaOH this is present as a carboxylate salt (RCOO− Na+). Only after an acid workup is the carboxylate protonated to the carboxylic acid. So the species formed first is the carboxylate salt, with the alcohol as the other product.

Base-promoted ester hydrolysis (saponification) proceeds when hydroxide attacks the carbonyl carbon, forming a tetrahedral intermediate. The OR' group leaves as RO-, which is quickly protonated by water to ROH. The acyl portion becomes a carboxylate (RCOO-). In the presence of NaOH this is present as a carboxylate salt (RCOO− Na+). Only after an acid workup is the carboxylate protonated to the carboxylic acid. So the species formed first is the carboxylate salt, with the alcohol as the other product.

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