See image — IUPAC and Nomenclature Chemistry Question

💡 Solution & Explanation

Step 1 - Identify the compound: The structure shown is OHC-CH2-CO-CH3, a four-carbon compound with an aldehyde (-CHO) at one end and a ketone (C=O) within the chain. Step 2 - Identify the principal characteristic group: In IUPAC nomenclature, when both an aldehyde and a ketone are present, the aldehyde has higher priority and is chosen as the principal characteristic group, receiving the suffix '-al'. Step 3 - Number the parent chain: The longest carbon chain containing the aldehyde carbon is numbered starting from the aldehyde carbon (C1). The chain is: C1(CHO)-C2(CH2)-C3(C=O)-C4(CH3), giving a four-carbon parent chain 'butanal'. Step 4 - Name the substituent/secondary group: The ketone at C3 is expressed as a prefix 'oxo-' with locant 3, since the suffix is already taken by the aldehyde. Step 5 - Assemble the name: Parent chain = butanal; oxo substituent at C3 = 3-oxo; full name = 3-oxobutanal. Step 6 - No other options are present to eliminate, but alternate names like 'succinaldehyde' or '3-ketobutanal' are not acceptable IUPAC names. Therefore, the correct answer is 3-oxobutanal.