Question

Which one of the following substituents at para-position is most effective in stabilizing the phenoxide ion ?

• A. $-CH_3$
• B. $-OCH_3$
• C. $-COCH_3$
• D. $-CH_2OH$

Answer 1

Answer: (C)

$-COCH_3$

Answer 2

Electron withdrawing group stabilises the benzene ring due to delocalisation of charge.

$-CH_{3} \, and -CH_{2}OH$ are electron donating group and hence decrease the stability of benzene ring $-OCH_{3}$ is weaker electron withdrawing group than $-COCH_{3}.$ Hence $-COCH_{3}.$ group more stabilize the phenoxide ion at p-position.