Write the IUPAC name of the given compound. A 3-ethyl-2 methyl pentane B 3-ethyl-4 methyl pentane C 2-methyl-3 ethyl pentane D 3,3-diethyl pentane

To determine the IUPAC name of the given compound, we need to analyze each option according to the IUPAC nomenclature rules.

1. Identify the longest carbon chain (parent chain): This will help in determining the base name (pentane in this case, since it's a 5-carbon chain).

2. Identify and locate the substituents: The substituents (ethyl and methyl groups) must be named and numbered based on their positions on the parent chain.

3. Determine the correct order of substituents: The order and numbering of substituents should be such that the sum of the locants of the first occurrence of each substituent is minimized.

Analysis of the Options:

• A. 3-ethyl-2-methylpentane

  • Longest chain: Pentane (5 Carbons)
  • Substituents: Ethyl at C-3 and Methyl at C-2.

• B. 3-ethyl-4-methylpentane

  • Longest chain: Pentane
  • Substituents: Ethyl at C-3 and Methyl at C-4.

• C. 2-methyl-3-ethylpentane

  • Longest chain: Pentane
  • Substituents: Methyl at C-2 and Ethyl at C-3 (same as option A but the order of substituents is different).

• D. 3,3-diethylpentane

  • Longest chain: Pentane
  • Substituents: Diethyl at C-3 (two ethyl groups at the same carbon).

Summary:

To properly name using IUPAC conventions, we recognize that options A and C are essentially describing the same compound, but A is correctly ordered.

The final answer, therefore, with respect to the IUPAC nomenclature rules and the common naming conventions should be:

Final Answer:

The IUPAC name is: 3-ethyl-2-methylpentane (Option A).