Benzne reacts with formaldehyde and dry `HCl` gas in the precence of anhdous `ZnCl_(2)` to form

Options

A. benzotrichloride
B. benzal chloride
C. benzyl chloride
D. benzoyl chloride

Explanation

To solve the question regarding the reaction of benzene with formaldehyde and dry HCl in the presence of anhydrous ZnCl2, we can follow these steps:

### Step 1: Identify the Reactants
The reactants in this reaction are:
- Benzene (C6H6)
- Formaldehyde (HCHO)
- Dry HCl (hydrochloric acid)
- Anhydrous ZnCl2 (zinc chloride)

### Step 2: Understand the Role of ZnCl2
Anhydrous ZnCl2 acts as a Lewis acid catalyst. It helps in the generation of the electrophile from formaldehyde and HCl.

### Step 3: Formation of the Electrophile
When formaldehyde reacts with dry HCl in the presence of ZnCl2, it forms a chloromethyl cation (CH2Cl+). The reaction can be summarized as follows:
- HCHO + HCl → CH2Cl+ + ZnCl2 → CH2Cl+ + ZnO

### Step 4: Electrophilic Substitution Reaction
The generated chloromethyl cation (CH2Cl+) is a strong electrophile. Benzene, being rich in electrons, can undergo electrophilic substitution with this cation. The reaction can be represented as:
- C6H6 + CH2Cl+ → C6H5CH2Cl (Benzyl chloride)

### Step 5: Final Product
The final product of the reaction is benzyl chloride (C6H5CH2Cl).

### Conclusion
Thus, when benzene reacts with formaldehyde and dry HCl in the presence of anhydrous ZnCl2, the product formed is benzyl chloride.