Treatment of propionaldehyde with dil. NaOH solution gives

Options

A. `CH_(3)CH_(2)COOCH_(2)CH_(2)CH_(3)`
B. `CH_(3)CH_(2)CHOHCH(CH_(3))CHO`
C. `CH_(3)CH_(2)CHOHCH_(2)CH_(2)CHO`
D. `CH_(3)CH_(2)COCH_(2)CH_(2)CHO`

Explanation

To solve the question regarding the treatment of propionaldehyde with dilute NaOH solution, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Structure of Propionaldehyde**:
- Propionaldehyde, also known as propanal, has the chemical formula CH3CH2CHO. It consists of a three-carbon chain with an aldehyde functional group at one end.

2. **Understand the Reaction Conditions**:
- The reaction involves treating propionaldehyde with dilute sodium hydroxide (NaOH). This is a basic condition that can lead to an aldol condensation reaction.

3. **Formation of Enolate Ion**:
- In the presence of a base like NaOH, the alpha hydrogen (the hydrogen attached to the carbon adjacent to the carbonyl group) of propionaldehyde can be removed. This results in the formation of an enolate ion:
\[ CH3CH2C(=O)H \rightarrow CH3CH2C^{-} + H2O \]

4. **Nucleophilic Attack**:
- The enolate ion acts as a nucleophile and attacks the carbonyl carbon of another molecule of propionaldehyde. This forms a β-hydroxy aldehyde (an aldol):
\[ CH3CH2C^{-} + CH3CH2CHO \rightarrow CH3CH2C(OH)(CH2CH3)CHO \]

5. **Formation of Aldol Product**:
- The product formed from the above reaction is 3-hydroxybutanal (an aldol). The structure can be represented as:
\[ CH3CH2C(OH)(CH2CHO) \text{ or } CH3CH(OH)CH2CHO \]

6. **Dehydration (if applicable)**:
- Under certain conditions (e.g., heating), the aldol product can undergo dehydration to form an α,β-unsaturated aldehyde. However, if we are only considering the immediate product of the reaction with dilute NaOH, we will focus on the aldol product.

7. **Final Product**:
- The final product of the reaction between propionaldehyde and dilute NaOH is 3-hydroxybutanal.

### Summary:
The treatment of propionaldehyde with dilute NaOH results in the formation of 3-hydroxybutanal (an aldol product).

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