The reaction of ethyl p - amiobenzoate with `HNO_2` and then with `HBF_4` yields a compounds (X), a crystalline ionic compound. Compound (X) , when heated forms `C_9H_9O_2F`(Y). The compound (Y) is

Options

A. ethyl p - fluorobenzoate
B. ethyl o - fluorobenzoate
C. ethyl m - fluorobenzoate
D. mixture of all the above

Answer

To solve the problem, we will follow the steps outlined in the video transcript and analyze the reactions involved.

### Step 1: Identify the starting compound
The starting compound is ethyl p-amino benzoate, which can be represented as follows:
- Structure:
- Benzene ring with a carboxylate group (COOEt) and an amino group (NH2) at the para position.

### Step 2: Reaction with HNO2
When ethyl p-amino benzoate reacts with nitrous acid (HNO2), it undergoes diazotization. The amino group (NH2) is converted into a diazonium salt (N2+):
- Reaction:
- Ethyl p-amino benzoate + HNO2 → Ethyl p-diazobenzenoate (ionic compound X) + N2 (gas)

### Step 3: Reaction with HBF4
The diazonium salt (ionic compound X) is then treated with tetrafluoroborate acid (HBF4). This results in the formation of a stable diazonium tetrafluoroborate salt:
- Reaction:
- Ethyl p-diazobenzenoate + HBF4 → Ethyl p-diazobenzenoate BF4 (compound X)

### Step 4: Heating compound X
When compound X is heated, it undergoes a rearrangement or decomposition that leads to the formation of a new compound:
- Result:
- Heating compound X leads to the formation of a compound with the formula C9H9O2F (compound Y).

### Step 5: Identify compound Y
To identify compound Y, we analyze the molecular formula C9H9O2F. This suggests that the compound is likely an ethyl ester of a fluorinated benzoic acid:
- Structure:
- The compound can be identified as ethyl para-fluorobenzoate.

### Final Answer
Thus, the compound (Y) formed after heating is **ethyl para-fluorobenzoate**.

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