See image — GOC and Organic Chemistry Basics Chemistry Question

💡 Solution & Explanation

# Electron Density at Benzene Ring Analysis **Key Principle:** Electron-donating groups increase electron density on the benzene ring; electron-withdrawing groups decrease it. ## Classifying Each Substituent: **I. $-COOEt$ (ethoxycarbonyl):** Strongly electron-withdrawing - The carbonyl carbon is highly electronegative and withdraws electrons through the $\sigma$-bond - Minimal resonance donation due to oxygen being attached to carbonyl carbon - **Lowest electron density** **II. $-OCOEt$ (ethoxycarbonyl via oxygen):** Moderately electron-withdrawing - Oxygen can donate electrons by resonance (+M effect) - But the carbonyl withdraws electrons (–I effect dominates slightly) - **Lower electron density** **III. $-CH_3$ (methyl):** Electron-donating - Alkyl groups donate electrons through the inductive effect (+I) - **Higher electron density** **IV. $-NHCOCH_3$ (acetamido):** Strongly electron-donating - Nitrogen has a lone pair that can donate electrons by resonance (+M effect) - Though carbonyl slightly withdraws, resonance from $N$ dominates - **Highest electron density** ## Order of Electron Density: $$IV > III > II > I$$ $$\text{(Acetamido > Methyl > Ethoxycarbonyl via O > Ethoxycarbonyl)}$$ **The answer is (D):** $IV > II > III > I$ is incorrect — the correct order is $IV > III > II > I$, which matches option **(D)** as stated in the problem.