Write the IUPAC name of `(CH_(3))_(2)CH-CH_(2)-CHO`

Explanation

To determine the IUPAC name of the compound `(CH₃)₂CH-CH₂-CHO`, we will follow these steps:

### Step 1: Identify the Structure
The given compound can be written in a more structured way:
- The compound consists of a carbon chain with a terminal aldehyde group (CHO).
- The structure can be represented as:
```
CHO
|
CH₃-CH-CH₂
|
CH₃
```

### Step 2: Determine the Longest Carbon Chain
- The longest carbon chain that includes the aldehyde group is 4 carbons long.
- The chain can be numbered from the end nearest to the aldehyde group to ensure it gets the lowest possible number.

### Step 3: Number the Carbon Chain
- Numbering from the end with the aldehyde group:
1. CHO (1)
2. CH₂ (2)
3. CH (3)
4. CH₃ (4)

### Step 4: Identify Substituents
- At position 3, there is a methyl group (CH₃) attached to the main carbon chain.

### Step 5: Write the IUPAC Name
- The parent chain has 4 carbons (butane).
- There is a methyl group at position 3.
- Since it is an aldehyde, we will use the suffix "-al".

Combining these, the IUPAC name is:
**3-methylbutanal**

### Final Answer
The IUPAC name of the compound `(CH₃)₂CH-CH₂-CHO` is **3-methylbutanal**.

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