Question

Identify the end-product [D] formed when solution salicylate undergoes the following series of reactions

Answer 1

Allyl phenyl ether (phenyl allyl ether)

Answer 2

Step 1: Decarboxylation
Under NaOH/CaO and heat, the salicylate ion loses CO₂ to give phenoxide.
$$\ce{C6H4(OH)COO^- ->[NaOH/CaO, ;\Delta] C6H5O^- + CO2}$$

Step 2: Acidification
Acid workup (HCl) converts phenoxide to phenol.
$$\ce{C6H5O^- + HCl -> C6H5OH + Cl^-}$$

Step 3: Williamson Ether Synthesis
Phenol in NaOH(aq) forms phenoxide again, which reacts with allyl bromide via S_N2 to yield allyl phenyl ether.
$$\ce{C6H5O^- + CH2=CHCH2Br -> C6H5OCH2CH=CH2 + Br^-}$$

Key point: Phenol undergoes Williamson ether synthesis with allyl bromide to give the allyl ether.