See image — IUPAC and Nomenclature Chemistry Question

💡 Solution & Explanation

Step 1: Identify the structure. The compound is: CH3-CH2-CH(Cl)-CH(CH3)-C(OH)(CH3) wait, let me re-read. The structure shown is CH3—CH2—CH—CH—C—CH3 with Cl on C3 (the CH), CH3 on C4 (the CH), and OH on C5 (the C). But C5 also has CH3 attached (the terminal CH3). So the full structure is: C1(CH3)-C2(H2)-C3(H)(Cl)-C4(H)(CH3)-C5(OH)(CH3)-... wait, let me recount. Step 2: Count the chain. Reading left to right: CH3(1) — CH2(2) — CH(Cl)(3) — CH(CH3)(4) — C(OH)(5) — CH3(6). Carbon 5 has OH and is bonded to CH3 (C6) and CH3 branch... Actually C5 has substituents: OH and the CH3 shown below, plus it connects to C4 and C6(CH3). So C5 is C(OH)(CH3) connected to C4 and C6. That means C5 has: bond to C4, bond to C6, OH, and a methyl branch — making it a quaternary carbon with OH. Step 3: The longest chain. The main chain contains 6 carbons: C1-C2-C3-C4-C5-C6 = hexane backbone. Step 4: Number from the end nearest the principal characteristic group (OH). Numbering from right (C6 end): C6=1, C5=2, C4=3, C3=4, C2=5, C1=6. This gives OH at position 2. Step 5: Identify substituents with this numbering: - OH at C2 (hexan-2-ol) - CH3 at C2 (2-methyl) - CH3 at C3 (3-methyl) - Cl at C4 (4-chloro) Step 6: Compile the name. Substituents listed alphabetically: 4-Chloro, 2-methyl, 3-methyl → 4-Chloro-2,3-dimethylhexan-2-ol. Step 7: Why other options fail: - (b) uses 'hydroxy' as a prefix instead of the suffix '-ol', which is incorrect when OH is the principal group. - (c) 'trimethylpentan-2-ol' implies a 5-carbon chain with three methyls, which does not match the structure. - (d) '3-Chloro-2,3-dimethylhexane-2-ol' places Cl at C3 and methyl at C3, but correct numbering gives Cl at C4. Therefore, the correct answer is A.