Among the following the strongest base is

Options

A. `C_(6)H_(5)NH_(2)`
B. `p-NO_(2)-C_(6)H_(4)NH_(2)`
C. `m-NO_(2)-C_(6)H_(4)NH_(2)`
D. `C_(6)H_(5)CH_(2)NH_(2)`

Answer

To determine which of the given compounds is the strongest base among the options, we will analyze the basicity of each compound based on the presence of electron-donating and electron-withdrawing groups.

### Step-by-Step Solution:

1. **Identify the Compounds**:
- The compounds given are:
1. Aniline (C6H5NH2)
2. Para-nitroaniline (C6H4(NO2)NH2)
3. Meta-nitroaniline (C6H4(NO2)NH2)
4. Benzylamine (C6H5CH2NH2)

2. **Understand Basicity in Amines**:
- Basicity in amines is primarily due to the lone pair of electrons on the nitrogen atom. The availability of this lone pair for protonation determines the basic strength.
- Electron-donating groups (EDGs) increase basicity by increasing electron density on nitrogen, while electron-withdrawing groups (EWGs) decrease basicity by reducing electron density.

3. **Analyze Each Compound**:
- **Aniline (C6H5NH2)**: The lone pair on nitrogen is partially delocalized into the benzene ring due to resonance, which reduces its availability for protonation. Therefore, it is less basic.
- **Para-nitroaniline (C6H4(NO2)NH2)**: The nitro group (-NO2) is a strong electron-withdrawing group. Its presence at the para position further decreases the basicity of the amine compared to aniline.
- **Meta-nitroaniline (C6H4(NO2)NH2)**: Similar to para-nitroaniline, the nitro group at the meta position also withdraws electron density, making it less basic than aniline.
- **Benzylamine (C6H5CH2NH2)**: The amine group is not directly attached to the benzene ring, so the lone pair on nitrogen is more available for protonation. Additionally, the benzyl group can exhibit some electron-donating character, enhancing the basicity.

4. **Compare Basicity**:
- Among the compounds analyzed:
- Aniline is less basic than benzylamine due to resonance.
- Para-nitroaniline and meta-nitroaniline are even less basic than aniline due to the strong electron-withdrawing effect of the nitro group.
- Benzylamine has the highest basicity because the lone pair on nitrogen is more available for protonation.

5. **Conclusion**:
- Based on the analysis, the strongest base among the given options is **Benzylamine (C6H5CH2NH2)**.

### Final Answer:
The strongest base among the given options is **Benzylamine (C6H5CH2NH2)**.