See image — IUPAC and Nomenclature Chemistry Question

💡 Solution & Explanation

Step 1: Identify the structure. The molecule shown has two carbonyl groups: an aldehyde (–CHO) on the left end and a ketone carbonyl (C=O) connected to a methyl group (–CH3) on the right. This gives the chain: OHC–CO–CH3, a three-carbon compound. Step 2: Determine the parent chain. There are three carbons in total: C1 (aldehyde carbon), C2 (ketone carbonyl carbon), C3 (methyl carbon). The parent chain is propan-1-al (propanal) since the aldehyde gets the lowest locant (C1). Step 3: Identify substituents/functional groups. C2 bears a ketone (oxo) group. In IUPAC nomenclature, a keto group on the chain is indicated by the prefix 'oxo-' with its locant when the principal characteristic group (aldehyde) is already named as the suffix. Step 4: Construct the name. Parent chain = propanal (3 carbons, aldehyde as suffix). The oxo group is at position 2. Therefore the name is 2-oxopropanal. Step 5: Why this is correct. The aldehyde (–CHO) is the principal characteristic group (higher seniority than ketone in IUPAC 2013 recommendations), so it is expressed as the suffix '-al'. The ketone at C2 is expressed as the prefix 'oxo-'. Combined: 2-oxopropanal. Therefore, the correct answer is 2-oxopropanal.