Which of the following is formed when ` RNH_2` reacts with ` RCHO`?

Options

A. Hemiacetals
B. Acetals
C. Ketals
D. Imines

Explanation

To determine what is formed when an amine (RNH₂) reacts with an aldehyde (RCHO), we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Reactants**:
- We have an amine (RNH₂) and an aldehyde (RCHO).
- The aldehyde contains a carbonyl group (C=O) and a hydrogen atom (H) attached to the carbon.

2. **Understand the Reaction Mechanism**:
- When an amine reacts with an aldehyde, a nucleophilic addition occurs. The nitrogen atom from the amine attacks the carbon atom of the carbonyl group in the aldehyde.

3. **Formation of an Intermediate**:
- The nitrogen from the amine forms a bond with the carbon of the aldehyde, leading to the formation of a tetrahedral intermediate. This intermediate has a hydroxyl group (OH) and an amine group (NH2) attached to the carbon.

4. **Elimination of Water**:
- The next step involves the elimination of a water molecule (H₂O). This occurs when the hydroxyl group (OH) from the intermediate is removed along with a hydrogen atom from the amine.

5. **Formation of the Final Product**:
- After the elimination of water, a double bond is formed between the carbon and the nitrogen, resulting in the formation of an imine (R1C=NR2).
- The general structure of the imine can be represented as R1C=NR2, where R1 is the original carbon chain from the aldehyde and R2 is the alkyl or aryl group from the amine.

6. **Conclusion**:
- The product formed from the reaction of RNH₂ with RCHO is an imine.

### Final Answer:
The product formed when RNH₂ reacts with RCHO is **imine**.

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