See image — IUPAC and Nomenclature Chemistry Question

💡 Solution & Explanation

Step 1 - Identify the parent ring: The structure is a cyclopenta-1,3-diene (cyclopentadienyl) ring, a five-membered carbocyclic ring containing two conjugated double bonds. Step 2 - Identify substituents and their positions: - A hydroxyl group (OH) is attached to one of the ring carbons. - A chlorine (Cl) is attached to another ring carbon involved in the double bond system. - An isopropenyl group (CH2=C(CH3)-) is attached to a ring carbon. Step 3 - Number the ring to give lowest locants to substituents and double bonds: - The OH-bearing carbon is assigned C1 (hydroxy group gets priority as principal characteristic group). - The double bonds run C1=C2 and C3=C4, giving cyclopenta-1,3-dien-1-ol as the base name. - Cl is on C3 (on the second double bond carbon adjacent to the isopropenyl-bearing carbon). - The isopropenyl (1-methylethenyl) group is on C5. Step 4 - Name the isopropenyl substituent: CH2=C(CH3)- is formally 1-methylethenyl (the ethenyl group with a methyl substituent on C1 of the vinyl). Step 5 - Assemble the full IUPAC name: Substituents in alphabetical order as prefixes: 3-chloro-5-(1-methylethenyl), parent chain: cyclopenta-1,3-dien-1-ol. Full name: 3-chloro-5-(1-methylethenyl)cyclopenta-1,3-dien-1-ol. Therefore, the correct answer is 3-chloro-5-(1-methylethenyl)cyclopenta-1,3-dien-1-ol.