See image — Isomerism and Stereochemistry Chemistry Question

💡 Solution & Explanation

# IUPAC Nomenclature of the Compound **Step 1: Identify the main chain** The longest carbon chain contains 8 carbons with three double bonds → **oct-2,4,6-triene** (base name) **Step 2: Number the chain to give lowest locants to double bonds** - Start from the end nearest to the first double bond - Numbering from left: double bonds at positions 2, 4, 6 ✓ - Numbering from right: double bonds at positions 2, 4, 6 (same locants) - However, the methyl substituent determines priority: it's at position 4 from the left **Step 3: Identify the methyl substituent position** - The methyl group is attached to carbon 4 of the main chain - When numbering from the left (giving the first double bond the lower number 2), the methyl is at position **4** **Step 4: Determine E/Z configuration** At each double bond, apply CIP rules: - **C-2 double bond**: has $CH_3$ and $CH$ as priority groups → **E** configuration - **C-4 double bond**: methyl substituent on one side, $CH$ on the other → **Z** configuration - **C-6 double bond**: $CH$ on one side, $H$ on the other → **E** configuration **Step 5: Write the complete name** $$\text{2E, 4Z, 6E-4-methyloct-2,4,6-triene}$$ **Answer: (D)** — Option D correctly lists all E/Z designations and positions the methyl group at carbon 4.