See image — IUPAC and Nomenclature Chemistry Question

💡 Solution & Explanation

Step 1 - Identify the structure: The compound shown is CH3-CH(CH3)-CH(CH3)-CH2NH2, where the dots above C2 and C3 indicate methyl substituents on those carbons. The full expanded structure is: CH3-CH(CH3)-CH(CH3)-CH2NH2. Step 2 - Identify the principal characteristic group: The principal characteristic group is the amine (-NH2), which gets the lowest possible locant. Amines are named as alkanamines. Step 3 - Identify the longest carbon chain containing the -NH2 group: The longest chain containing -CH2NH2 is four carbons: C1(CH2NH2)-C2(CH with methyl)-C3(CH with methyl)-C4(CH3). This gives a butane backbone. Step 4 - Number the chain: Number from the end nearest to the -NH2 group to give it the lowest locant. Numbering from the CH2NH2 end: C1 = CH2NH2, C2 = CH(CH3), C3 = CH(CH3), C4 = CH3. The amine is at C1. Step 5 - Identify substituents: There are methyl groups at C2 and C3. Step 6 - Construct the name: Parent chain = butane (4 carbons), principal group = amine at position 1, substituents = 2,3-dimethyl. Full name: 2,3-Dimethylbutan-1-amine. Step 7 - Eliminate wrong options: (a) 2,3-Dimethylbutan-4-amine: incorrect because the -NH2 would be at C4, but numbering should give lowest locant to -NH2, so it should be C1. (b) 2,4-Dimethylbutan-1-amine: incorrect because methyls are at C2 and C3, not C2 and C4. (c) 2,4-Dimethylbutan-4-amine: incorrect on both substituent positions and amine position. Therefore, the correct answer is D.