An organic compound (A) with molecular formula `C_(6)H_(6)O` gives a characteristic colour with aqueous `FeCl_(3)` solution. When (A) is treated with `CO_(2)` and NaoH at 410 K under pressure, it gives compound (B) which upon acidification gives compound (C). compound (C) reacts with acetyl chloride to give (D) which is a popular pain killer. deduce the structure of (A), (B), (C) and (D) and explain all the reaction involved.

Explanation

(i) Since copound (A) with M.F. `C_(6)H_(6)O` gives characteristic colour with `FeCl_(3)`, therefore (A) must be phenol.
(ii) Since compound (A), i.e., phenol reacts with `CO_(2)` and NaOH under pressure (i.e., Kolbe's reaction) to to give compound (B) which on acidification gives compound (C), therefore, (B) must be sodium salicylate and (C) must be salicylic acid.
(iii) Since (C) reacts with acetyl chloride to form a popular paiin killer (D), therefore, (D) must be aspirin.
(iv) All the abbveo reactions may be explained as follows: