The IUPAC name of `OHC"C"H=CH-underset(CH_(2)CH_(2)CH_(2)CH_(3))underset(|)(CH)-CH=CH_(2)` is

Options

A. 5-Vinyloct-3-en-1-al
B. 4-Butylhexa-2, 5-dien-1-al
C. 5-Vinyloct-5-en-8-al
D. 3-Butylhexa-1, 4-dien-8-al.

Explanation

To determine the IUPAC name of the given compound `OHC"C"H=CH-underset(CH_(2)CH_(2)CH_(2)CH_(3))underset(|)(CH)-CH=CH_(2)`, we will follow these steps:

### Step 1: Identify the Longest Carbon Chain
First, we need to identify the longest continuous carbon chain in the structure.

- The structure has a total of 8 carbon atoms in the longest chain, which includes double bonds.

### Step 2: Number the Carbon Chain
Next, we will number the carbon chain starting from the end nearest to the first substituent or double bond.

- Numbering from the left, we get:
1. C1 - CHO (aldehyde)
2. C2 - C
3. C3 - CH
4. C4 - CH
5. C5 - CH
6. C6 - CH
7. C7 - CH2
8. C8 - CH3 (butyl group)

### Step 3: Identify Substituents and Their Positions
Now, we need to identify any substituents and their positions on the main chain.

- There is a butyl group (C4H9) attached to C4.
- There are also two double bonds located between C2-C3 and C5-C6.

### Step 4: Write the Name
Now we can write the IUPAC name based on the information gathered.

- The main chain is an octa- (8 carbons) with two double bonds (diene).
- The substituent is a butyl group at C4.
- The double bonds are located at C2 and C5.

Putting it all together, the IUPAC name is:
**4-butyl-octa-2,5-diene**

### Step 5: Confirm the Name
Finally, we should confirm that the name follows IUPAC nomenclature rules.

- The longest chain is correctly identified.
- The substituent is correctly placed.
- The double bonds are indicated with the correct locants.

Thus, the final IUPAC name of the compound is **4-butyl-octa-2,5-diene**.

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