See image — Isomerism and Stereochemistry Chemistry Question

💡 Solution & Explanation

# Why Enantiomers Differ in Reactivity with Chiral Reagents **Key Concept:** Enantiomers are non-superimposable mirror images with identical connectivity but opposite stereochemistry at chiral centers. **Analysis of each option:** **(A) Solubility in achiral solvent** — ✗ Incorrect - In achiral solvents, enantiomers experience identical intermolecular forces since the solvent cannot distinguish between left- and right-handed molecules - Solubilities are equal **(C) Melting point** — ✗ Incorrect - Pure enantiomers (optically pure) have identical melting points - Crystal packing forces depend only on molecular shape and size, not stereochemical orientation in achiral environments **(D) Optical rotation** — ✗ Incorrect - While enantiomers rotate plane-polarized light in *opposite directions* (±), the **magnitude** of rotation is identical: $|[\alpha]_D^{R}| = |[\alpha]_D^{S}|$ **(B) Reactivity with achiral reagent** — ✓ **CORRECT** When a chiral reagent reacts with enantiomers: $$\text{(R)-substrate} + \text{chiral reagent} \rightarrow \text{diastereomeric transition states}$$ $$\text{(S)-substrate} + \text{chiral reagent} \rightarrow \text{different diastereomeric transition states}$$ The diastereomeric intermediates/products have different free energies, leading to **different reaction rates and product distributions**. This is the basis for chiral resolution and enantioselective synthesis. **Answer: (B)**