See image — IUPAC and Nomenclature Chemistry Question

💡 Solution & Explanation

Step 1: Identify the parent chain and principal functional group. The molecule contains a ketone (C=O) group. One side of the carbonyl is an aryl group (substituted benzene ring), and the other side is an aliphatic chain. For an aryl ketone, we treat the aryl group as a substituent and name the compound as an aryl alkanone, or we can name it as a phenyl ketone. The IUPAC approach: find the longest carbon chain including the carbonyl carbon on the aliphatic side. The chain on the aliphatic side is -CH2-CH2-CH(Br)-CH3, which is 4 carbons. Including the carbonyl carbon itself makes 5 carbons total (pentan-1-one backbone). Step 2: Number the chain. The carbonyl carbon is C1, so the chain is: C1(=O)-C2H2-C3H2-C4H(Br)-C5H3. This gives a pentan-1-one backbone. Step 3: Identify substituents on the aliphatic chain. There is a bromine on C4, giving 4-bromopentan-1-one as the base aliphatic portion. Step 4: Identify the aryl substituent at C1. The benzene ring attached to C1 has two substituents: bromine and chlorine. Numbering the ring from the point of attachment (C1 of ring = ipso), going around to minimize locants: Br is at position 3 and Cl is at position 4 of the phenyl ring. Thus the aryl group is 3-bromo-4-chlorophenyl. Step 5: Assemble the full name. The compound is 1-(3-bromo-4-chlorophenyl)-4-bromopentan-1-one, which by alphabetical ordering of substituents in the full name is written as 4-bromo-1-(3-bromo-4-chlorophenyl)pentan-1-one. Step 6: Verify ring substitution pattern. The bromine on the ring is meta to the carbonyl attachment and the chlorine is para to it (adjacent to Br), consistent with 3-bromo-4-chloro substitution. Therefore, the correct answer is 4-bromo-1-(3-bromo-4-chlorophenyl)pentan-1-one.