If an ester labeled in the carbonyl oxygen with 18O is reacted with aqueous NaOH, what would be the result?
Hint 1. How to reason this out
In light of the addition-elimination mechanism, consider the fate of the tetrahedral intermediates formed in the reaction.
ANSWER:
| Recovered ester would have less of the label than at the beginning of the reaction. |
| The alcohol from the hydrolysis would contain the 18O label. |
| Recovered ester would now have the 18O in the alkoxy oxygen. |
|
Can you explain why the answer is the first option. |
when ester is treated with NaOH, hydrolysis takes place and ester is broken doen to carboxylic acid and alcohol. But as the reaction is reversible, the newly formed carboxylic acid and alcohol will react to form ester.
As some of the ester has hydrolysed to its components, the amount recovered will be less than begining of the reaction.
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