The IUPAC name of of `(CH_3)_2CH-CH_2-CH_2-CH_2`Br is

Options

A. 1-bromopentane
B. 1-bromo-4-methypentane
C. 2-methy-4-bromobutane
D. 2-methyl-3-bromopantane.

Answer

To determine the IUPAC name of the compound `(CH₃)₂CH-CH₂-CH₂-CH₂Br`, we will follow these steps:

### Step 1: Identify the Structure
The given compound can be represented as:
- Two methyl groups attached to a carbon (isopropyl group).
- This is followed by a straight chain of three methylene groups (CH₂).

### Step 2: Count the Carbon Atoms
Count the total number of carbon atoms in the longest continuous chain:
- The longest chain consists of 5 carbon atoms (C1, C2, C3, C4, C5).

### Step 3: Identify the Functional Group
The compound contains a bromine (Br) atom as a substituent.

### Step 4: Number the Carbon Chain
Number the carbon chain starting from the end closest to the bromine atom to give the substituents the lowest possible numbers:
- Start numbering from the end nearest to the Br:
- C1 (Br), C2, C3, C4, C5.

### Step 5: Identify the Substituents
- The bromine is on carbon 1 (C1).
- There is a methyl group on carbon 4 (C4).

### Step 6: Combine the Information
Now we can combine the information to write the IUPAC name:
- The bromine substituent is named first, followed by the position of the methyl group.
- The base name is derived from the longest carbon chain, which is pentane (5 carbon atoms).

### Step 7: Write the Final Name
Putting it all together, the IUPAC name of the compound is:
**1-bromo-4-methylpentane**

### Summary of the Steps:
1. Identify the structure and count carbon atoms.
2. Identify the functional group (Br).
3. Number the chain from the end nearest to the functional group.
4. Identify and name the substituents.
5. Combine the information to write the final IUPAC name.