Question

The major product D formed in the following reaction sequence is:

• A.
• B.
• C. CH3CH2OH
• D. CH3CH2Cl

Answer 1

Answer: (C)

CH3CH2OH

Answer 2

Let’s trace the reaction sequence
Step 1: $CH_3OH$ (methanol) reacts with thionyl chloride $(SOCl_2)$ to form chloromethane (A):
$CH_3OH + SOCl_2 → CH_3Cl (A) + SO_2 + HCl$

Step 2: $CH_3Cl$ reacts with potassium cyanide (KCN) in aqueous ethanol to form acetonitrile (B):
$CH_3Cl + KCN → CH_3CN (B) + KCl$

Step 3: Acetonitrile (B) is reduced using sodium amalgam $(Na(Hg))$ in ethanol to form ethylamine (C):
$CH_3CN (B)$ $CH_3CH_2NH_2 (C)$

Step 4: Ethylamine (C) undergoes diazotization with sodium nitrite and hydrochloric acid $(NaNO_2/HCl)$, followed by hydrolysis with water $(H_2O)$ to produce ethanol (D) as the major product:

Conclusion: The major product D is ethanol $(CH_3CH_2OH).$