See image — GOC and Organic Chemistry Basics Chemistry Question

💡 Solution & Explanation

## Analysis of Carbanion Stability **Carbanion stability depends on:** The ability to delocalize the negative charge into the aromatic ring through resonance. **Evaluating each option:** **(1) Phenylethyl carbanion ($C_6H_5-CH_2-\overset{\ominus}{CH_2}$)** - The negative charge is on a saturated carbon away from the ring - Minimal resonance stabilization - Least stable **(2) Benzyl carbanion ($C_6H_5-\overset{\ominus}{CH_2}$)** ✓ - Negative charge is directly attached to the aromatic ring - Can delocalize into the $\pi$ system via resonance - Forms stable allylic-type carbanion with ortho/para distribution - **Most stable** **(3) Para-methoxybenzyl carbanion ($CH_3O-C_6H_4-\overset{\ominus}{CH_2}$)** - Negative charge can delocalize into ring - BUT $OCH_3$ (electron-donating group) destabilizes the carbanion by pushing electron density, making the negative charge less stabilized - More stable than (1), less than (2) **(4) Para-nitrobenzyl carbanion ($NO_2-C_6H_4-\overset{\ominus}{CH_2}$)** - $NO_2$ is electron-withdrawing, which deactivates resonance stabilization - Decreases carbanion stability - Less stable than (2) **Answer: (2)** — The benzyl carbanion is most stable because the negative charge can be directly resonance-stabilized by the aromatic ring without interference from other substituents.