How many benzylic H - atoms are present in mestitylene ?

Options

A. 9
B. 6
C. 3
D. None of these

Answer

To determine the number of benzylic hydrogen atoms in mesitylene, we can follow these steps:

### Step 1: Understand the Structure of Mesitylene
Mesitylene, also known as 1,3,5-trimethylbenzene, has a benzene ring with three methyl (–CH₃) groups attached to it. The structure can be represented as follows:

```
CH3
|
CH3-C6H3-CH3
```

### Step 2: Identify the Benzylic Carbons
Benzylic carbons are the carbon atoms that are directly attached to the benzene ring. In mesitylene, the three methyl groups are attached to the benzene ring, and the carbons in these methyl groups are not considered benzylic carbons. The benzylic carbons are the ones directly attached to the benzene.

### Step 3: Count the Benzylic Hydrogen Atoms
Each benzylic carbon can have hydrogen atoms attached to it. In mesitylene, the benzene ring has six carbon atoms, and three of these carbons are connected to the methyl groups. The remaining three carbons in the benzene ring are connected to one hydrogen atom each.

- Each of the three benzylic carbons (the ones attached to the benzene) has one hydrogen atom.
- Therefore, the total number of benzylic hydrogen atoms is 3 (one from each of the three benzylic carbons).

### Step 4: Conclusion
Thus, the total number of benzylic hydrogen atoms in mesitylene is 3.

### Final Answer
The number of benzylic H-atoms present in mesitylene is **3**.

---