The IUPAC name of `CH_(3)-CH=CHCH_(2)Br` is :

Options

A. 1-Bromo-2 butene
B. 1-Bromo-2 butene
C. 2-butene-1- bromide
D. Fiting reaction

Explanation

To determine the IUPAC name of the compound `CH₃-CH=CH-CH₂Br`, we will follow these steps:

### Step 1: Identify the longest carbon chain
The longest carbon chain in the compound consists of four carbon atoms. This chain is identified as follows:
- Start from the left: `CH₃-CH=CH-CH₂Br`
- Count the carbon atoms: 1 (from CH₃), 2 (from CH), 3 (from CH), and 4 (from CH₂Br).

### Step 2: Number the carbon chain
To assign the correct numbers to the carbon atoms, we need to give the substituents (in this case, bromine) the lowest possible number.
- Start numbering from the end closest to the bromine atom:
- C1: CH₂Br
- C2: CH
- C3: CH
- C4: CH₃
So, the numbering is: 1 (Br) - 2 (double bond) - 3 - 4.

### Step 3: Identify the functional groups and their positions
- The compound contains a double bond between C2 and C3.
- There is a bromine substituent at C1.

### Step 4: Write the IUPAC name
According to IUPAC nomenclature:
- The base name for a four-carbon alkene is "butene".
- The position of the double bond is at C2, so we use "2-butene".
- Since there is a bromine substituent at C1, we prefix it with "1-bromo".

Combining these, the IUPAC name of the compound is **1-bromo-2-butene**.

### Final Answer
The IUPAC name of `CH₃-CH=CH-CH₂Br` is **1-bromo-2-butene**.

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