An acid chloride treated with a primary amine yields which product?

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Multiple Choice

An acid chloride treated with a primary amine yields which product?

Acid chlorides are highly reactive toward amines and undergo nucleophilic acyl substitution to form amides. The lone pair on the amine nitrogen attacks the carbonyl carbon of the acid chloride, a tetrahedral intermediate forms, and chloride leaves. With a primary amine (R'NH2), one hydrogen is replaced by the acyl group, so the nitrogen ends up attached to the carbonyl carbon, to the attached R' group, and still has one hydrogen. That gives a product of the form R-CO-NH-R', which is a secondary amide. A primary amide (R-CO-NH2) would require no R' substituent on nitrogen, which isn’t produced in this reaction with a primary amine. The other options correspond to different pathways (ester formation with alcohols, carboxylic acid formation by hydrolysis, etc.), not this amide-forming reaction.

Acid chlorides are highly reactive toward amines and undergo nucleophilic acyl substitution to form amides. The lone pair on the amine nitrogen attacks the carbonyl carbon of the acid chloride, a tetrahedral intermediate forms, and chloride leaves. With a primary amine (R'NH2), one hydrogen is replaced by the acyl group, so the nitrogen ends up attached to the carbonyl carbon, to the attached R' group, and still has one hydrogen. That gives a product of the form R-CO-NH-R', which is a secondary amide.

A primary amide (R-CO-NH2) would require no R' substituent on nitrogen, which isn’t produced in this reaction with a primary amine. The other options correspond to different pathways (ester formation with alcohols, carboxylic acid formation by hydrolysis, etc.), not this amide-forming reaction.

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