Question

Alkyl cyanides undergo Stephen reduction to produce

• A. aldehyde
• B. secondary amine
• C. primary amine
• D. amide

Hint:

Stephen reduction: \(R-CN \rightarrow R-CHO\) (nitrile to aldehyde) using \(SnCl_2/HCl\) followed by hydrolysis.

Answer 1

The Correct Option is A

Step 1: Recall Stephen reduction.
Stephen reduction is the partial reduction of nitriles (\(R-CN\)) using \(\text{SnCl}_2/HCl\).
Step 2: Intermediate formation.
Nitrile is reduced to iminium salt:
\[ R-CN \xrightarrow{SnCl_2/HCl} R-CH=NH\cdot HCl \]
Step 3: Hydrolysis gives aldehyde.
On hydrolysis:
\[ R-CH=NH \xrightarrow{H_2O} R-CHO \]
Step 4: Conclusion.
Hence alkyl cyanides give aldehydes in Stephen reduction.
Final Answer:
\[ \boxed{\text{(A) aldehyde}} \]