The IUPAC name of tertiary butyl chloride is

Options

A. 2-chloro-2-methypropane
B. 3-chlorobutane
C. 4-chlorobutane
D. 1,2-chloro-3-methylpropane

Answer

To determine the IUPAC name of tertiary butyl chloride, we can follow these steps:

### Step 1: Identify the Structure
Tertiary butyl chloride has the following structure:
- It consists of a central carbon atom bonded to three methyl groups (CH₃) and one chlorine atom (Cl).

### Step 2: Count the Carbon Atoms
In the structure of tertiary butyl chloride:
- There are four carbon atoms in total.

### Step 3: Determine the Parent Chain
- The longest continuous carbon chain in tertiary butyl chloride consists of three carbon atoms. Therefore, the parent chain is propane.

### Step 4: Identify the Substituents
- The chlorine atom (Cl) is a substituent on the second carbon of the propane chain.
- There is also a methyl group (CH₃) attached to the same carbon (the second carbon).

### Step 5: Number the Carbon Chain
- Number the carbon chain from one end to the other to give the substituents the lowest possible numbers. In this case, we start from the end closest to the chlorine atom.

### Step 6: Assign Locants to Substituents
- The chlorine substituent is on the second carbon, and the methyl group is also on the second carbon.

### Step 7: Write the IUPAC Name
- According to IUPAC nomenclature, we list the substituents in alphabetical order, followed by the name of the parent chain.
- Therefore, the IUPAC name is 2-chloro-2-methylpropane.

### Final Answer
The IUPAC name of tertiary butyl chloride is **2-chloro-2-methylpropane**.

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