Aniline on treatment with excess of bromine water gives

Options

A. 2-bromoaniline
B. 4-bromoaniline
C. 2,4,6-tribromoaniline
D. 2,6-dibromoaniline

Answer

To solve the question, "Aniline on treatment with excess of bromine water gives," we will follow these steps:

### Step 1: Understand the Structure of Aniline
Aniline is an aromatic amine with the chemical formula C6H5NH2. The NH2 group (amino group) is attached to a benzene ring.

### Step 2: Identify the Reaction Type
When aniline reacts with bromine water, it undergoes an electrophilic substitution reaction. The amino group (NH2) is a strong activating group for the aromatic ring, which increases the electron density of the ring.

### Step 3: Determine the Position of Substitution
The NH2 group is ortho- and para-directing due to its electron-donating nature. This means that bromine will preferentially add to the ortho and para positions of the benzene ring.

### Step 4: Draw the Resonance Structures
The lone pair of electrons on the nitrogen atom can delocalize into the benzene ring, enhancing the electron density at the ortho and para positions. This can be illustrated by drawing the resonance structures of aniline, showing how the lone pair contributes to the aromatic system.

### Step 5: Predict the Product
When excess bromine water is added to aniline, bromination occurs at both the ortho and para positions. Since we have excess bromine, we expect multiple bromine atoms to be substituted onto the ring.

### Step 6: Identify the Final Product
The final product will be 2,4,6-tribromoaniline, where three bromine atoms are substituted at the 2, 4, and 6 positions relative to the amino group on the benzene ring.

### Final Answer
Thus, the product formed when aniline is treated with excess bromine water is **2,4,6-tribromoaniline**.

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