Question

Alkyl halide on heating with alc.NH\(_3\) in a sealed tube results ....

• A. 1° amine
• B. 2° amine
• C. 3° amine
• D. all of these

Hint:

Hoffmann's ammonolysis gives mixture of primary, secondary, tertiary amines.

Answer 1

The Correct Option is D

The question asks about the product formed when an alkyl halide is heated with alcoholic ammonia (\(\text{alc.NH}_3\)) in a sealed tube. Let's analyze the reaction step by step:

• Initial Reaction: When an alkyl halide (R-X) reacts with alcoholic ammonia, the first product formed is a primary amine (R-NH₂). This occurs via nucleophilic substitution where the halogen atom (X) is replaced by the -NH₂ group:

R-X + NH3 → R-NH2 + HX

• Secondary Reaction: The primary amine (R-NH₂) formed can further react with another molecule of alkyl halide to form a secondary amine (R₂NH):

R-X + R-NH2 → R2NH + HX

• Tertiary Reaction: The secondary amine can further react with the alkyl halide to form a tertiary amine (R₃N):

R-X + R2NH → R3N + HX

• Conclusion: Depending on the reaction conditions, all three types of amines (primary, secondary, and tertiary) can be formed. Hence, the correct answer to the question is "all of these."

Thus, when alkyl halide is heated with alcoholic ammonia in a sealed tube, it can result in the formation of all types of amines: primary, secondary, and tertiary.