Secondary amines could be prepared by

Options

A. reduction of nitro compounds
B. reduction of amides
C. reduction of isonitriles
D. reduction of isonitriles

Answer

To prepare secondary amines, we can utilize the reduction of isonitriles. Here’s a step-by-step explanation of the process:

### Step-by-Step Solution:

1. **Understanding Isonitriles**:
- Isonitriles (also known as isocyanides) have the general structure R-N≡C, where R is an alkyl or aryl group. They are characterized by the presence of a carbon-nitrogen triple bond.

2. **Reduction Process**:
- To convert isonitriles into secondary amines, we need to perform a reduction reaction. This can be achieved using reducing agents such as lithium aluminium hydride (LiAlH4) or catalytic hydrogenation (H2 with a catalyst).

3. **Reaction Mechanism**:
- When isonitriles are treated with LiAlH4, the carbon-nitrogen triple bond is reduced. The reaction can be represented as follows:
\[ R-N≡C + 2[H] \xrightarrow{LiAlH4} R-NH-CH2 \]
- Here, the isonitrile (R-N≡C) is reduced to form a secondary amine (R-NH-CH2).

4. **Final Product**:
- The product of this reduction is a secondary amine, which has the general structure R-NH-R', where R' is derived from the original isonitrile.

5. **Conclusion**:
- Therefore, the correct method for preparing secondary amines is through the reduction of isonitriles.

### Final Answer:
Secondary amines could be prepared by the reduction of isonitriles.

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