The IUPAC name of the compound `CH_(3)COCH (CH_(3))_(2)` is :

Options

A. Isopropyl methyl ketone
B. 2-Methylbutane-3-one
C. 4-Methylisopropyl ketone
D. 3-Methylbutane-2-one.

Explanation

To determine the IUPAC name of the compound \( CH_3COCH(CH_3)_2 \), we will follow these steps:

### Step 1: Identify the Structure
The given compound can be broken down as follows:
- The compound has a ketone functional group (indicated by the carbonyl group \( C=O \)).
- The structure can be visualized as:

```
CH3
|
CH3-C-CO-CH3
|
CH3
```

### Step 2: Determine the Longest Carbon Chain
To name the compound, we need to identify the longest continuous carbon chain that includes the carbonyl group. In this case, the longest chain consists of four carbon atoms, which includes the carbonyl carbon.

### Step 3: Number the Carbon Chain
Number the carbon chain starting from the end nearest to the carbonyl group (ketone). This gives us the following numbering:
- Carbon 1: \( CH_3 \) (methyl group)
- Carbon 2: \( CO \) (ketone group)
- Carbon 3: \( CH \) (attached to two methyl groups)
- Carbon 4: \( CH_3 \) (methyl group)

### Step 4: Identify Substituents
From the numbering:
- At Carbon 3, there are two methyl groups attached. Therefore, we denote this as "dimethyl".
- The ketone group is at Carbon 2.

### Step 5: Construct the IUPAC Name
Based on the information gathered:
- The longest chain has 4 carbons, which corresponds to the root name "but".
- The ketone functional group is at position 2, so we use "2-one".
- The two methyl groups at position 3 are denoted as "3,3-dimethyl".

Putting it all together, the IUPAC name of the compound is:
**3,3-Dimethylbutan-2-one**

### Final Answer
The IUPAC name of the compound \( CH_3COCH(CH_3)_2 \) is **3,3-Dimethylbutan-2-one**.

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