How will you convert ethanal into the following compounds?
But-2-enoic acid.

Explanation

To convert ethanal (acetaldehyde, CH3CHO) into but-2-enoic acid (CH3CH=CHCOOH), we can follow these steps:

### Step 1: Aldol Condensation
1. **React Ethanal with Dilute NaOH**:
- Ethanal (CH3CHO) has an alpha hydrogen that can participate in an aldol condensation reaction.
- When two moles of ethanal react in the presence of dilute NaOH, they undergo aldol condensation to form 3-hydroxybutanal (CH3CH(OH)CH2CHO).
- The reaction can be represented as:
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