Concept:The carboxylation of a phenoxide ion under high pressure is a specific named organic synthesis for manufacturing salicylic acid (a precursor to aspirin).
Formula:$$ \text{C}_6\text{H}_5\text{ONa} + \text{CO}_2 \xrightarrow{\text{High P, T}} \text{Sodium salicylate} \xrightarrow{\text{H}^+} \text{Salicylic acid} $$
Solution:- Sodium phenoxide reacts with carbon dioxide (a weak electrophile) because the phenoxide ring is intensely activated.
- This specific electrophilic addition of \(\text{CO}_2\) followed by rearrangement is formally known as the Kolbe Schmitt reaction.
Why other options are incorrect:Williamson synthesis makes ethers from alkoxides and alkyl halides. Aldol and Cannizzaro reactions involve aldehydes/ketones, completely unrelated to phenol carboxylation.
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