A third group is least likely to enter between two groups in the meta relationship. This is the result of steric hindrance and increases in importance with the size of the groups on the ring and with the size of the attacking species.
When a Meat-directing group is meta to an ortho-para directing group, the incoming group primarily goes ortho th the meta directing group rather than para.
Chlorination of `m-`chloro nitro benzene gives :

Options

A.
B.
C.
D.

Answer

To determine the product of the chlorination of m-chloro-nitrobenzene, we need to analyze the positions where the chlorine can be introduced based on the directing effects of the existing substituents and the steric hindrance involved. Here’s a step-by-step breakdown of the solution:

### Step 1: Identify the Structure of m-Chloro-Nitrobenzene
- The compound m-chloro-nitrobenzene has a chlorine (Cl) group and a nitro (NO2) group on a benzene ring. The chlorine is ortho-para directing, while the nitro group is meta directing.

### Step 2: Determine the Directing Effects
- Chlorine (Cl) is an ortho-para directing group, which means it will direct incoming electrophiles (like Cl+) to the ortho and para positions relative to itself.
- The nitro group (NO2) is a meta directing group, which means it will direct incoming electrophiles to the meta position relative to itself.

### Step 3: Analyze the Positions for Chlorination
- The chlorine can potentially attack at the following positions:
1. Ortho to the chlorine (which is also ortho to the nitro)
2. Para to the chlorine (which is meta to the nitro)
3. Meta to the chlorine (which is para to the nitro)

### Step 4: Consider Steric Hindrance
- When considering the ortho position relative to the nitro group, we must take into account steric hindrance. The nitro group is bulky, and placing a chlorine atom at the ortho position would create significant steric hindrance.
- Therefore, even though the chlorine prefers to attack ortho to the chlorine, the presence of the nitro group makes this position unfavorable.

### Step 5: Determine the Most Favorable Position
- Given the steric hindrance at the ortho position, the chlorine will preferentially attack the para position relative to the nitro group. This position is less hindered and allows for a more stable product formation.

### Step 6: Draw the Product
- The product of the chlorination of m-chloro-nitrobenzene will be 1-chloro-2-nitrobenzene, where the chlorine is positioned para to the nitro group.

### Final Product
- The final product of the chlorination of m-chloro-nitrobenzene is **1-chloro-2-nitrobenzene**.

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