An ester reacts with ammonia in ethanol. Which products form?

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Multiple Choice

An ester reacts with ammonia in ethanol. Which products form?

Nucleophilic acyl substitution of esters by ammonia gives an amide and an alcohol. Here, ammonia uses its lone pair to attack the carbonyl carbon of the ester, forming a tetrahedral intermediate. This intermediate then collapses and the alkoxy leaving group is expelled as RO−. That alkoxide is protonated (by the protonated ammonia or solvent) to form the corresponding alcohol. The nitrogen remains attached to the carbonyl carbon, yielding the amide (R-CO-NH2). So the overall transformation is ester plus ammonia → amide plus alcohol. The other possibilities would require preserving the original ester, forming a carboxylate salt, or giving an ammonium salt, which don’t align with the typical substitution pathway under these conditions.

Nucleophilic acyl substitution of esters by ammonia gives an amide and an alcohol. Here, ammonia uses its lone pair to attack the carbonyl carbon of the ester, forming a tetrahedral intermediate. This intermediate then collapses and the alkoxy leaving group is expelled as RO−. That alkoxide is protonated (by the protonated ammonia or solvent) to form the corresponding alcohol. The nitrogen remains attached to the carbonyl carbon, yielding the amide (R-CO-NH2).

So the overall transformation is ester plus ammonia → amide plus alcohol. The other possibilities would require preserving the original ester, forming a carboxylate salt, or giving an ammonium salt, which don’t align with the typical substitution pathway under these conditions.

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