See image — IUPAC and Nomenclature Chemistry Question

💡 Solution & Explanation

Concept: IUPAC nomenclature of aromatic amines (anilines). The parent compound for an aromatic amine (ArNH2) is benzenamine (systematic name for aniline). Step 1: Identify the principal characteristic group. The NH2 (amino) group is the principal characteristic group and gets the lowest locant. It is assigned position 1 on the benzene ring. Step 2: Identify substituents. Bromine (Br) is at the para position relative to NH2, which is position 4. Step 3: Construct the name. The parent chain is benzenamine (benzene + amine suffix). The bromo substituent at position 4 gives the prefix '4-bromo'. Full name: 4-Bromobenzenamine. Evaluating other options: (b) 4-Amino-1-bromobenzene incorrectly treats Br as the principal group at position 1 and NH2 as a substituent prefix, which violates IUPAC priority rules since NH2 has higher seniority than halogens. (c) 4-Bromo benzenamide is incorrect because 'amide' refers to -CONH2 or -C(=O)NH2 functional group, not a primary amine. (d) 1-Bromo benzencarboxamide is incorrect for the same reason and also implies a carboxamide group. Therefore, the correct answer is A.