Which of the following is most basic?

Options

A. Benzylamine
B. Aniline
C. Acetanilide
D. p-nitroaniline

Answer

To determine which compound among the given options is the most basic, we need to analyze the structures and the factors that influence basicity. Basicity is the ability of a compound to accept protons (H⁺ ions) or donate a lone pair of electrons.

### Step-by-Step Solution:

1. **Identify the Compounds**:
Let's assume the options are:
- A: Benzylamine (C6H5CH2NH2)
- B: Paranitroaniline (C6H4(NH2)(NO2))
- C: Aniline (C6H5NH2)
- D: N,N-Dimethylamine (C2H7N)

2. **Understand Basicity**:
Basicity is influenced by the availability of the lone pair of electrons on the nitrogen atom. The more available the lone pair, the stronger the base.

3. **Analyze Electron-Withdrawing Groups**:
- In Paranitroaniline, the nitro group (NO2) is an electron-withdrawing group. It decreases the electron density on the nitrogen atom, making it less basic.
- In contrast, Benzylamine does not have any strong electron-withdrawing groups attached to the nitrogen, which keeps the electron density high.

4. **Compare Basicity**:
- **Benzylamine**: The nitrogen has a lone pair that is not significantly delocalized or withdrawn by any substituents, making it a strong base.
- **Paranitroaniline**: The presence of the nitro group decreases the basicity due to the withdrawal of electron density.
- **Aniline**: Similar to Paranitroaniline, but less affected by the nitro group, so it is more basic than Paranitroaniline but less than Benzylamine.
- **N,N-Dimethylamine**: This compound has two methyl groups that donate electron density to the nitrogen, making it a strong base.

5. **Conclusion**:
After analyzing the compounds, Benzylamine (option A) is the most basic because it has a nitrogen atom with a readily available lone pair, unaffected by electron-withdrawing groups.

### Final Answer:
The most basic compound among the options is **A: Benzylamine**.

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