Which reagents form a primary amide in the scheme?

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

Which reagents form a primary amide in the scheme?

Nucleophilic acyl substitution of an acid chloride by ammonia gives a primary amide. The ammonia supplies an NH2 group that substitutes for the chloride on the carbonyl carbon, yielding R‑CO‑NH2 and releasing Cl− (which is usually neutralized by the ammonium formed). This is why acid chloride reacting with ammonia produces a primary amide. If water were used, the acid chloride would be hydrolyzed to the carboxylic acid. If an alcohol were used, it would form the corresponding ester (R‑COOR). Using a base alone won’t introduce nitrogen to form an amide either. Hence the only option that forms a primary amide is the acid chloride reacting with ammonia.

Nucleophilic acyl substitution of an acid chloride by ammonia gives a primary amide. The ammonia supplies an NH2 group that substitutes for the chloride on the carbonyl carbon, yielding R‑CO‑NH2 and releasing Cl− (which is usually neutralized by the ammonium formed). This is why acid chloride reacting with ammonia produces a primary amide.

If water were used, the acid chloride would be hydrolyzed to the carboxylic acid. If an alcohol were used, it would form the corresponding ester (R‑COOR). Using a base alone won’t introduce nitrogen to form an amide either. Hence the only option that forms a primary amide is the acid chloride reacting with ammonia.

More practice questions