IUPAC nomenclature of
`CH_3-underset(CH_2-CH_3)underset(|)overset(CH_3)overset(|)C-CH=overset(CH_3)overset(|)C-CH_3` is

Options

A. 4 - ethyl -2, 4 - dimethylpent - 2 - ene
B. 2,4,4 - trimethylhex - 2- ene
C. 3,3,5 - trimethylhex -4 -ene
D. 2,2,4 - trimethylhex -3 -ene

Answer

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

### Step 1: Draw the Structure
First, we need to visualize the structure based on the provided formula. The compound can be represented as follows:

```
CH3
|
CH3-CH2-C-CH=CH-C-CH3
|
CH3
```

### Step 2: Identify the Longest Carbon Chain
Next, we identify the longest continuous carbon chain that includes the double bond. In this case, the longest chain consists of 6 carbon atoms.

### Step 3: Number the Carbon Chain
We will number the carbon chain starting from the end closest to the double bond to give the double bond the lowest possible number. This means we will number the chain as follows:

```
1 2 3 4 5 6
CH3-CH2-C-CH=CH-C-CH3
```

### Step 4: Identify Substituents
Now, we identify the substituents on the main carbon chain:
- At carbon 2, there is one methyl group (CH3).
- At carbon 4, there are two methyl groups (CH3).

### Step 5: Write the Name
Now we can compile the name:
- The substituents are: 2-methyl and 4,4-dimethyl.
- The parent chain is hexane (since it has 6 carbons).
- The presence of a double bond at position 2 indicates that we have an alkene, which we denote as "hex-2-ene".

Putting it all together, the full IUPAC name is:
**2,4,4-trimethylhex-2-ene**

### Final Answer
The IUPAC nomenclature of the compound is **2,4,4-trimethylhex-2-ene**.

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