The IUPAC name of `(CH_3)_2 CHCH_2Br` is

Options

A. 1 - bromo - 2- methylpropane
B. 2 - bromo - 2- methylpropane
C. 1 - bromo - 1- methylpropane
D. 2 - bromo - 1- methylpropane

Explanation

To determine the IUPAC name of the compound `(CH_3)_2 CHCH_2Br`, we can follow these steps:

### Step 1: Identify the Structure
The given compound can be expanded to show its structure:
- The compound consists of a branched alkane with a bromine atom attached.
- The structure can be drawn as:

```
CH3
|
CH3 - C - CH2 - Br
|
H
```

### Step 2: Determine the Longest Carbon Chain
- Identify the longest continuous carbon chain in the structure.
- In this case, the longest chain has 4 carbon atoms (butyl group).

### Step 3: Number the Carbon Chain
- Number the carbon chain from the end nearest to the substituent (bromine).
- The numbering will be as follows:

```
1 - CH2Br
2 - CH
3 - CH3
4 - CH3
```

### Step 4: Identify Substituents
- There is one bromine atom (Br) and two methyl groups (CH3) as substituents.
- The bromine is on carbon 1, and the two methyl groups are on carbon 2.

### Step 5: Write the Name
- Combine the substituents and the parent chain name:
- The substituents are named in alphabetical order: "bromo" comes before "methyl".
- The name of the longest chain (4 carbons) is "butane".

Thus, the IUPAC name is:
**2,2-Dimethyl-1-bromobutane**

### Final Answer
The IUPAC name of `(CH_3)_2 CHCH_2Br` is **2,2-Dimethyl-1-bromobutane**.

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