Aniline is an activated system for electrophilic substitution The compounds formed on heating aniline with acetic anhydride is .

Options

A.
B.
C.
D.

Explanation

To solve the question regarding the reaction of aniline with acetic anhydride, we will follow these steps:

### Step 1: Identify the Reactants
Aniline is an aromatic amine with the formula C6H5NH2. Acetic anhydride is represented as (CH3CO)2O.

### Step 2: Understand the Reaction
Aniline is an activated system for electrophilic substitution due to the presence of the amino group (-NH2), which is a strong activating group. When aniline reacts with acetic anhydride, it undergoes acylation, where the acyl group from the anhydride replaces one of the hydrogen atoms on the nitrogen of aniline.

### Step 3: Write the Reaction
The reaction can be represented as follows:
\[ \text{C}_6\text{H}_5\text{NH}_2 + \text{(CH}_3\text{CO)}_2\text{O} \rightarrow \text{C}_6\text{H}_5\text{NHCOCH}_3 + \text{CH}_3\text{COOH} \]

### Step 4: Identify the Products
The main product formed from this reaction is acetanilide (C6H5NHCOCH3), which is an amide formed by the acylation of aniline. The by-product of the reaction is acetic acid (CH3COOH).

### Step 5: Conclusion
Thus, when aniline is heated with acetic anhydride, the compound formed is **acetanilide**.

### Final Answer
The compound formed on heating aniline with acetic anhydride is **acetanilide**.

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