See image — IUPAC and Nomenclature Chemistry Question

💡 Solution & Explanation

Step 1: Identify the functional groups. The molecule contains two ketone (C=O) groups, making it a dione. Step 2: Count the carbon chain. Starting from the left: CH3 (C1) - C=O (C2) - CH (C3) - CH (C4) - CH2 (C5) - C=O (C6) - CH3 (C7). This gives a 7-carbon chain, so the parent chain is heptane. Step 3: Identify substituents. At C3 there is a methyl branch, and at C4 there is a methyl branch, giving 3,4-dimethyl substitution. Step 4: Locate the ketone groups. The carbonyl groups are at C2 and C6, so the compound is a 2,6-dione. Step 5: Combine the name. Parent chain = heptane, substituents = 3,4-dimethyl, functional groups = 2,6-dione. Full IUPAC name = 3,4-dimethylheptane-2,6-dione. Step 6: Verify numbering gives lowest locants. Numbering from the other end would place carbonyls at C2 and C6 as well (symmetric in locant set), but the methyl groups would be at C4 and C5, giving 4,5-dimethylheptane-2,6-dione. Comparing locant sets: {2,3,4,6} vs {2,4,5,6} — at the first point of difference, 3 < 4, so the first numbering (3,4-dimethylheptane-2,6-dione) is correct. Therefore, the correct answer is 3,4-dimethylheptane-2,6-dione.