Question

An organic compound "A" on treatment with benzene sulphonyl chloride gives compound B. B is soluble in dil. NaOH solution. Compound A is :

• A. C₆H₅ - CH₂ - NH - CH₃
• B. C₆H₅ - N(CH₃)₂
• C. C₆H₅ - NH - CH₂ - CH₃
• D. C₆H₅ - CH₂ - NH₂

Hint:

Hinsberg Test Summary: $1^\circ \rightarrow$ Soluble; $2^\circ \rightarrow$ Insoluble; $3^\circ \rightarrow$ No reaction.

Answer 1

The Correct Option is D

Step 1: This is the Hinsberg Test.
Step 2: Primary amines (\(1^\circ\)) react with benzene sulphonyl chloride to form a sulphonamide that is soluble in alkali due to the presence of an acidic hydrogen on the Nitrogen.
Step 3: Secondary amines (\(2^\circ\)) form a sulphonamide that is insoluble in alkali. Tertiary amines (\(3^\circ\)) do not react.
Step 4: From the options, only (D) Benzyl amine is a primary amine.