What is the correct IUPAC name of the following compound?
` CH_3 CH_2CH_2 CH_2 CH_2 underset(CH_3 ) underset(| )(CH )- underset(CH_2 CH_2 CH_3) underset(|)overset(CH_3) overset(|) C- CH_2 CH_3`
3, 4-dimethyl-3n-propylnonane
6,7-dimethyl-2-n-propyinonane
6,7-dimethyl-7-ethyldecane
4,5-dimethyl-4-ethyldecane.

Options

A. 3, 4-dimethyl-3n-propylnonane
B. 6,7-dimethyl-2-n-propyinonane
C. 6,7-dimethyl-7-ethyldecane
D. 4,5-dimethyl-4-ethyldecane.

Explanation

To determine the correct IUPAC name of the given compound, we will follow these steps:

### Step 1: Identify the longest carbon chain
The first step in naming an organic compound is to identify the longest continuous carbon chain. In this case, we can see that the longest chain consists of 9 carbon atoms.

### Step 2: Number the carbon chain
Next, we need to number the carbon chain. The numbering should start from the end of the chain that gives the substituents the lowest possible numbers.

- If we start numbering from the left (1 to 9), we have:
1. C1
2. C2
3. C3
4. C4
5. C5
6. C6
7. C7
8. C8
9. C9

- If we start numbering from the right (1 to 9), we have:
1. C1
2. C2
3. C3
4. C4
5. C5
6. C6
7. C7
8. C8
9. C9

By comparing both methods, we find that starting from the right gives us lower numbers for the substituents.

### Step 3: Identify and name the substituents
From the numbering, we can identify the substituents:
- At C3, there is a propyl group (C3H7).
- At C4, there are two methyl groups (C2H6).

### Step 4: Write the IUPAC name
Now we can write the IUPAC name. According to IUPAC nomenclature:
- We list the substituents in alphabetical order.
- The substituents are 3-propyl and 3,4-dimethyl.

Thus, the name becomes:
- 3,4-dimethyl-3-n-propylnonane.

### Final Answer
The correct IUPAC name of the compound is **3,4-dimethyl-3-n-propylnonane**.

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