Question

Identify P, Q and R in the following reaction sequence:
\[ P \xrightarrow{\text{NH}_3} \text{CH}_3\text{COO}^- \text{NH}_4^+ \xrightarrow{\Delta} Q \xrightarrow{\text{PCl}_5} R \]

Hint:

In organic synthesis, reactions with \( \text{PCl}_5 \) are commonly used to convert amides into acyl chlorides.

Answer 1

- P is acetic acid (\( \text{CH}_3\text{COOH} \)), which reacts with ammonia (\( \text{NH}_3 \)) to form ammonium acetate (\( \text{CH}_3\text{COO}^- \text{NH}_4^+ \)).
- Q is acetamide (\( \text{CH}_3\text{CONH}_2 \)), which is formed upon heating ammonium acetate.
- R is acetyl chloride (\( \text{CH}_3\text{COCl} \)), which is produced by reacting acetamide with phosphorus pentachloride (\( \text{PCl}_5 \)).