See image — IUPAC and Nomenclature Chemistry Question

💡 Solution & Explanation

Step 1 - Identify the parent chain/ring: The structure contains a cyclohexane ring as the main cyclic framework. Step 2 - Identify the principal functional group: Attached to the cyclohexane ring is a -C(=O)-NH- group, which is an amide functional group. The full group is -C(=O)-NH-Ph, where Ph is a phenyl group. Step 3 - Name the acyl portion: A cyclohexane ring with a carboxyl-derived group (-C(=O)-) attached gives the parent acid name 'cyclohexanecarboxylic acid'; the corresponding amide base name is 'cyclohexanecarboxamide'. Step 4 - Name the N-substituent: The nitrogen bears a phenyl (Ph) substituent, which is indicated by the prefix 'N-phenyl'. Step 5 - Combine: The N-phenyl substituent on the amide nitrogen of cyclohexanecarboxamide gives the full IUPAC name 'N-phenylcyclohexane carboxamide'. No other options are present to eliminate. Therefore, the correct answer is N-phenylcyclohexane carboxamide.