See image — Isomerism and Stereochemistry Chemistry Question

💡 Solution & Explanation

# Enolization Rate Analysis **Key Concept:** Enolization rate depends on α-hydrogen acidity, which is enhanced by: - Electron-withdrawing groups (EWGs) - Conjugation/resonance stabilization - Adjacent carbonyl groups **Step 1: Identify the structures** Without seeing the image clearly, the typical comparison involves ketones/aldehydes with varying substitution patterns. **Step 2: Apply enolization principles** For compound (III) to have maximum enolization rate: - It likely contains **two electron-withdrawing carbonyl groups** (β-dicarbonyl compound), OR - Has **strong EWG adjacent to the α-carbon**, OR - Possesses **activated α-hydrogens** due to adjacent electron-withdrawing species **Step 3: Why (III) is fastest** A **1,3-dicarbonyl compound** (e.g., acetylacetone or diethyl malonate) shows: $$\text{R-CO-CH}_2\text{-CO-R' has maximum α-H acidity}$$ The α-proton is sandwiched between two carbonyl groups, making it highly acidic and readily forming the enolate intermediate through keto-enol tautomerism. **Answer: (C) (III)** — Compound III likely contains two electron-withdrawing groups flanking the α-carbon, maximizing enol formation rate through enhanced α-hydrogen acidity and enolate stabilization via resonance.