Which reaction sequence would be best to prepare 3-chloro-aniline form benzene

Options

A. nitration, reducing, chlorination
B. chlorination, nitration, reduction
C. nitration, chlorination, reduction
D. nitration, reduction, acetylation, chlorination, hydrolysis

Answer

To prepare 3-chloroaniline from benzene, we need to follow a specific sequence of reactions. Here is a step-by-step text solution:

### Step 1: Nitration of Benzene
- **Reaction**: Benzene (C6H6) is treated with a mixture of concentrated nitric acid (HNO3) and concentrated sulfuric acid (H2SO4).
- **Product**: This reaction introduces a nitro group (NO2) to the benzene ring, resulting in nitrobenzene (C6H5NO2).

### Step 2: Chlorination of Nitrobenzene
- **Reaction**: Nitrobenzene is then subjected to chlorination. This can be done using chlorine gas (Cl2) in the presence of a Lewis acid catalyst like aluminum chloride (AlCl3).
- **Product**: The chlorine atom will preferentially attach to the meta position relative to the nitro group due to the deactivating nature of the nitro group. This results in the formation of 3-chloro-nitrobenzene (C6H4ClNO2).

### Step 3: Reduction of 3-Chloro-nitrobenzene
- **Reaction**: The next step involves the reduction of the nitro group to an amino group (NH2). This can be achieved using zinc amalgam (Zn/Hg) in an acidic medium (like acetic acid).
- **Product**: The reduction converts the nitro group to an amino group, yielding 3-chloroaniline (C6H4ClNH2).

### Final Product
- The final product is 3-chloroaniline, which has the chlorine substituent at the meta position relative to the amino group.

### Summary of the Reaction Sequence:
1. Nitration of benzene → Nitrobenzene
2. Chlorination of nitrobenzene → 3-Chloro-nitrobenzene
3. Reduction of 3-chloro-nitrobenzene → 3-Chloroaniline

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