Which of the following is not possible directly in nitrobenzene?

Options

A. Halogenation
B. Sulphonation
C. Nitration
D. Alkylation

Explanation

To solve the question "Which of the following is not possible directly in nitrobenzene?", we need to analyze the effects of the nitro group (-NO2) on the reactivity of the benzene ring. Here’s a step-by-step solution:

### Step 1: Understand the Nature of the Nitro Group
The nitro group (-NO2) is a strong electron-withdrawing group. It pulls electron density away from the benzene ring through resonance and inductive effects. This significantly affects the reactivity of the benzene ring towards electrophilic substitution reactions.

**Hint:** Remember that electron-withdrawing groups decrease electron density on the aromatic ring, making it less reactive towards electrophiles.

### Step 2: Identify the Positions of Electrophilic Attack
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