Concept:In common nomenclature of aldehydes, the carbon chain is named after the corresponding carboxylic acid, and substituent positions are indicated by Greek letters starting from the carbon adjacent to the carbonyl group.
Solution:- The chain contains 3 continuous carbons ending in a formyl group, making the parent name "propionaldehyde".
- The carbon immediately attached to the \( -CHO \) group is the \( \alpha \)-carbon. Here, it has a methyl group attached.
- The next carbon along the chain is the \( \beta \)-carbon. Here, it has a chlorine atom attached.
- Arranging alphabetically, we get \( \beta \)-Chloro-\( \alpha \)-Methyl propionaldehyde.
Why other options are incorrect:The options mismatch the Greek letter assignments. There is no \( \gamma \) carbon in the main three-carbon chain of this specific molecule, making options A and B structurally impossible.
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