Which of the following the following in a `3^(@)` amine?

Options

A. Propan-2-amine
B. `N`- Methy1 ehtanamine
C. Ally1 amine
D. `N,N`-Diethy1 butan-1-amine

Explanation

To determine which of the given compounds is a tertiary amine, we need to analyze each compound based on the classification of amines. Amines can be classified as primary, secondary, or tertiary based on the number of carbon-containing groups (alkyl groups) attached to the nitrogen atom.

### Step-by-Step Solution:

1. **Identify the Compounds**: The question provides four compounds:
- Propan-2-amine
- N-methylethanamine
- Allylamine
- N,N-diethylbutanamine

2. **Classify Each Compound**:
- **Propan-2-amine**: This compound has one nitrogen atom bonded to one carbon chain (propane) and two hydrogen atoms. Therefore, it is classified as a **primary amine**.
- **N-methylethanamine**: In this compound, the nitrogen is bonded to one ethyl group and one methyl group, along with one hydrogen atom. This means it has two carbon groups and one hydrogen, classifying it as a **secondary amine**.
- **Allylamine**: This compound has one nitrogen atom bonded to one allyl group and two hydrogen atoms. Thus, it is classified as a **primary amine**.
- **N,N-diethylbutanamine**: Here, the nitrogen is bonded to two ethyl groups and one butyl group. This means it has three carbon groups attached to the nitrogen, classifying it as a **tertiary amine**.

3. **Conclusion**: The only compound that is a tertiary amine is **N,N-diethylbutanamine**.

### Final Answer:
The tertiary amine among the given options is **N,N-diethylbutanamine**.

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