JEE Main · 2021 · 27 Aug 2021 · Shift 2 · Haloalkanes and Haloarenes

With $K_{2}C{O}_3$ the phenol is first converted to phenoxide, the nucleophile. In an $S_{N}2$ process the nucleophile attacks, by direct back-side approach, the carbon that actually carries the leaving group, which here is the primary allylic $C{H}_2$ of prenyl bromide; no allylic rearrangement occurs. The major product is therefore the straight-chain prenyl phenyl ether, $PhO\text{-}C{H}_2\text{-}CH=C(C{H}_3{)}_2$.