Naming the Structure: The name “4-Methylpent-2-enal” provides the key structural features of the molecule. The “pent” indicates a five-carbon chain. “2-enal” indicates the presence of a double bond at the second carbon and an aldehyde group at the terminal position. The “4-methyl” substituent specifies a methyl group attached to the fourth carbon.
Construct the Structure Step-by-Step: Step 1: Place a five-carbon chain. Step 2: Insert a double bond between carbons 2 and 3. Step 3: Attach an aldehyde group (C=O with an H) to the first carbon. Step 4: Add a methyl group to the fourth carbon.
Verify Each Option: Only Option (4) matches this structure, with the correct placement of the double bond, aldehyde group, and methyl substituent.
Conclusion: The structure in Option (4) is correct for 4-Methylpent-2-enal.
