Question

An organic compound \( C_7H_5N \) on reduction with reagent X gave Y. Reaction of Y with p-toluene sulphonyl chloride gave Z which is insoluble in alkali. X and Y respectively are:

• A. \( \text{LiAlH}_4,\) 

  

• B. \( \text{NaBH}_4,\)

  

• C. \( \text{H}_2 | \text{Ni},\) 

  

• D. \( \text{H}_2 | \text{Ni},\) 

  

Hint:

- Always consider the structural implications of molecular formulas and the typical reactions of reducing agents. \( \text{H}_2/\text{Ni} \) is effective for reducing nitro, nitrile, and imine groups to amines.
- p-Toluene sulphonyl chloride is used to identify primary amines by forming insoluble sulphonamides.

Answer 1

The Correct Option is D

Step 1: Identification of Compound \( C_7H_5N \) 
- \( C_7H_5N \) suggests a structure likely to be benzylamine (benzene ring with an amine group attached through a methyl bridge, also considering the possible tautomeric or functional group transformations). 

Step 2: Reduction of \( C_7H_5N \) 
- Reduction using \( \text{H}_2 | \text{Ni} \) typically targets nitro groups, nitriles, or imines, suggesting the original compound might involve a nitrile or nitro group reducible to a primary amine. 

Step 3: Formation of Z with p-Toluene Sulphonyl Chloride 
- Reaction with p-toluene sulphonyl chloride typically involves the formation of a sulphonamide, which is insoluble in alkali due to its lack of free NH groups after transformation. This reaction is a test for primary amines, which confirms the amine was the reduction product Y. 

Step 4: Concluding the Reactions 
- The final product formed is benzylamine (\( C_6H_5CH_2NH_2 \)), a primary amine, indicating the original compound may have been a benzyl cyanide (\( C_6H_5CH_2CN \)) or similar structure reduced to the amine.