In the reaction of ethyl benzoate with ammonia under heating, what byproduct is formed alongside the major amide product?

Master NCEA Level 3 Organic Chemistry Reaction Schemes. Prepare with multiple choice questions, complete with hints and detailed explanations. Ace your exam with our comprehensive tools!

Multiple Choice

In the reaction of ethyl benzoate with ammonia under heating, what byproduct is formed alongside the major amide product?

Esters can undergo nucleophilic acyl substitution with ammonia to form amides and an alcohol. Here, ammonia attacks the carbonyl carbon of ethyl benzoate, creating a tetrahedral intermediate. The ethoxy group is expelled as the leaving group, yielding benzamide. In the reaction medium, the expelled ethoxide quickly grabs a proton to become ethanol, which is the byproduct. Heating drives this aminolysis toward the amide, while the alkoxy fragment ends up as the alcohol. Other options don’t fit the mechanism: water would come from hydrolysis, not aminolysis with ammonia; ethylamine would require a different leaving group situation; ammonium benzoate isn’t formed in this path. Ethanol is the correct byproduct.

Esters can undergo nucleophilic acyl substitution with ammonia to form amides and an alcohol. Here, ammonia attacks the carbonyl carbon of ethyl benzoate, creating a tetrahedral intermediate. The ethoxy group is expelled as the leaving group, yielding benzamide. In the reaction medium, the expelled ethoxide quickly grabs a proton to become ethanol, which is the byproduct. Heating drives this aminolysis toward the amide, while the alkoxy fragment ends up as the alcohol. Other options don’t fit the mechanism: water would come from hydrolysis, not aminolysis with ammonia; ethylamine would require a different leaving group situation; ammonium benzoate isn’t formed in this path. Ethanol is the correct byproduct.

More practice questions