A compound X with molecular formula `C_7H_8` is treated with `Cl_2` in presence of `FeCl_3`. Which of the following compounds are formed during the reaction?

Options

A.
B.
C.
D.

Explanation

To solve the question regarding the compound X with the molecular formula \( C_7H_8 \) treated with \( Cl_2 \) in the presence of \( FeCl_3 \), we can follow these steps:

### Step 1: Identify the Structure of Compound X
The molecular formula \( C_7H_8 \) suggests that the compound could be toluene, which has the structure of a benzene ring with a methyl group (\( CH_3 \)) attached. The structure can be represented as:

\[ \text{C}_6\text{H}_5\text{CH}_3 \]

### Step 2: Understand the Reaction Conditions
The reaction involves treating toluene with chlorine gas (\( Cl_2 \)) in the presence of iron(III) chloride (\( FeCl_3 \)). The \( FeCl_3 \) acts as a catalyst and helps generate the electrophile \( Cl^+ \).

### Step 3: Electrophilic Substitution Mechanism
The reaction proceeds via electrophilic aromatic substitution. In this mechanism, the \( Cl^+ \) electrophile attacks the aromatic ring of toluene.

### Step 4: Determine the Position of Substitution
The methyl group (\( CH_3 \)) is an electron-donating group, which directs the substitution to the ortho and para positions relative to itself. The possible substitution positions on the benzene ring are:

- Ortho position (adjacent to the \( CH_3 \))
- Para position (opposite to the \( CH_3 \))

### Step 5: Analyze Steric Hindrance
While both ortho and para positions are possible, the para position is generally favored due to less steric hindrance compared to the ortho position. Therefore, the major product will be the para-substituted compound.

### Step 6: Identify the Products
The major product formed from this reaction is para-chlorotoluene. The structure can be represented as:

\[ \text{C}_6\text{H}_4\text{Cl}\text{CH}_3 \quad (\text{para-chlorotoluene}) \]

### Conclusion
The compound formed during the reaction of toluene with \( Cl_2 \) in the presence of \( FeCl_3 \) is para-chlorotoluene.

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