See image — IUPAC and Nomenclature Chemistry Question

💡 Solution & Explanation

Step 1: Identify the parent chain. The longest carbon chain containing the amide (C=O-NH) group is the principal chain. Counting from the carbonyl carbon end: C1 is the carbonyl carbon, C2 is CH2, C3 has Cl, C4 has Cl, C5 has Br, C6 has Br, C7 is CH3. This gives a 7-carbon chain: heptanamide. Step 2: Identify the principal characteristic group. The amide group (-C(=O)-NH-) is the principal characteristic group, so the compound is named as an amide: heptanamide. Step 3: Number the chain. Numbering starts from the carbonyl carbon (C1) toward the substituents: C1 (C=O), C2 (CH2), C3 (CHCl), C4 (CHCl), C5 (CHBr), C6 (CHBr), C7 (CH3). Step 4: Identify and locate substituents on the chain. At C3: Cl; at C4: Cl; at C5: Br; at C6: Br. These give 3,4-dichloro and 5,6-dibromo substituents. Step 5: Identify the N-substituent. The nitrogen bears a 2-chloroethyl group (-CH2CH2Cl), so it is N-(2-chloroethyl). Step 6: Assemble the name. List substituents alphabetically: bromo before chloro. Combining: 5,6-dibromo-3,4-dichloro-N-(2-chloroethyl)heptanamide. Step 7: Verify numbering gives lowest locants to substituents — numbering from carbonyl end gives locants 3,4,5,6 vs. numbering from methyl end would give 2,3,4,5, but the carbonyl carbon must be C1 in amide nomenclature, so the numbering is fixed. Therefore, the correct answer is 5,6-dibromo-3,4-dichloro-N-(2-chloroethyl)heptanamide.