Which of the following compound is most reactive in the nucleophilic aromatic substitution reaction with NaOH ?

Options

A. `p-` nitrofluorobenezene
B. `p-`nitrochlorobenzene
C. `p-`nitrobromobenzene
D. `p-`nitroiodobenzene

Explanation

To determine which compound is most reactive in nucleophilic aromatic substitution reactions with NaOH, we need to consider the reactivity order of different aromatic halides. Here’s the step-by-step solution:

### Step 1: Understand Nucleophilic Aromatic Substitution
Nucleophilic aromatic substitution (NAS) occurs when a nucleophile attacks an aromatic ring that contains a leaving group (like a halogen). The leaving group must be able to stabilize the negative charge that forms during the reaction.

### Step 2: Identify the Reactivity Order
The reactivity of aromatic halides in nucleophilic aromatic substitution is influenced by the nature of the halogen. The general order of reactivity for halogens in nucleophilic aromatic substitution is:
- ArF (Fluorobenzene) > ArCl (Chlorobenzene) > ArBr (Bromobenzene) > ArI (Iodobenzene)

This means that fluorobenzene is the most reactive, followed by chlorobenzene, bromobenzene, and then iodobenzene.

### Step 3: Analyze the Given Options
Assuming the options provided are:
A. Fluorobenzene
B. Chlorobenzene
C. Bromobenzene
D. Iodobenzene

### Step 4: Determine the Most Reactive Compound
Based on the reactivity order established in Step 2, fluorobenzene (ArF) is the most reactive compound in nucleophilic aromatic substitution reactions with NaOH.

### Conclusion
Thus, the correct answer is:
**A. Fluorobenzene**