Aldol condensation of acetaldehyde involves the Formation of which of the following intermediate

Options

A. Acetate ion
B. A carbanion
C. A carbonium ion
D. A free radical

Answer

To solve the question regarding the aldol condensation of acetaldehyde and the formation of its intermediate, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Structure of Acetaldehyde**:
- Acetaldehyde has the molecular formula CH3CHO. It consists of a methyl group (CH3) and a carbonyl group (C=O) attached to a hydrogen atom.

2. **Understand Aldol Condensation**:
- Aldol condensation is a reaction between two aldehydes or one aldehyde and one ketone, where the initial product is a β-hydroxy aldehyde or ketone, which can further dehydrate to form an α,β-unsaturated carbonyl compound.

3. **Formation of the Enolate Ion**:
- Under basic conditions, the hydrogen atom on the alpha carbon (the carbon adjacent to the carbonyl group) of acetaldehyde can be abstracted by a base (OH-), leading to the formation of an enolate ion.
- The enolate ion is represented as CH2=C(OH)CH3, where the negative charge is on the alpha carbon.

4. **Nucleophilic Attack**:
- The enolate ion then acts as a nucleophile and attacks the carbonyl carbon of another acetaldehyde molecule. This results in the formation of a new carbon-carbon bond.

5. **Formation of the Aldol Product**:
- After the nucleophilic attack, a tetrahedral intermediate is formed, which can then lose a hydroxide ion (OH-) to yield the final aldol product, which is a β-hydroxy aldehyde.

6. **Identify the Intermediate**:
- The key intermediate formed during the aldol condensation of acetaldehyde is the **carbon anion** (enolate ion).

### Final Answer:
The intermediate formed during the aldol condensation of acetaldehyde is the **carbon anion**.

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