Ester containing `alpha-` hydrogens undergo self condensation in presence of a strong base such as sodium ethoxide to form `beta-` ketoesters. This reaction is called

Options

A. Aldol condensation
B. Claisen condensation
C. Diekmann condensation
D. Crossed - Claisen condensation

Answer

To solve the question regarding the reaction of esters containing alpha-hydrogens undergoing self-condensation in the presence of a strong base, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Reactants**:
- We start with an ester that contains alpha-hydrogens. An example of such an ester could be ethyl acetate (CH3COOCH2CH3).

2. **Role of Strong Base**:
- A strong base, such as sodium ethoxide (NaOEt), is used in this reaction. The strong base will abstract the alpha-hydrogen from the ester, creating an enolate ion.

3. **Formation of Enolate Ion**:
- The abstraction of the alpha-hydrogen leads to the formation of an enolate ion. This enolate ion is a nucleophile and is crucial for the next step of the reaction.

4. **Self-Condensation**:
- The enolate ion formed can then attack another molecule of the ester at the carbonyl carbon (the electrophilic site). This results in the formation of a beta-ketoester.

5. **Final Product**:
- The product of this self-condensation reaction is a beta-ketoester. For example, if we started with ethyl acetate, the product would be 3-oxobutanoate.

6. **Naming the Reaction**:
- The reaction that occurs is known as the **Claisen condensation**. This term specifically refers to the self-condensation of esters in the presence of a strong base to form beta-ketoesters.

### Final Answer:
The reaction is called **Claisen condensation**.