Answer
🔬 IUPAC Naming of Organic Molecules
🧪 Objective
Assign correct IUPAC names to the given organic compounds based on structure, functional groups, and substituents.
🔬 Molecule 1: Methyl Propanoate
Structure: Contains an ester functional group (–COO–) with a three-carbon acid portion and a methyl group attached to the oxygen.
Naming Logic
- Base chain (acid part): 3 carbon atoms → propanoate
- Alkyl group attached to oxygen: methyl
Final IUPAC Name:
Methyl propanoate
🔬 Molecule 2: 3-Methyl-2-butanone
Structure: A four-carbon ketone with the carbonyl group on the second carbon and a methyl group on the third carbon.
Naming Logic
- Longest carbon chain: 4 carbon atoms → butanone
- Carbonyl group at position 2 → numbered accordingly
- Methyl substituent at position 3
Final IUPAC Name:
3-Methyl-2-butanone
🧠Summary Table
| Molecule | Functional Group | Longest Chain | Substituents | IUPAC Name |
|---|---|---|---|---|
| 1 | Ester | 3 (propanoate) | Methyl on oxygen | Methyl propanoate |
| 2 | Ketone | 4 (butanone) | Methyl at C-3 | 3-Methyl-2-butanone |
Conclusion
- Identify the principal functional group and use it to determine the suffix.
- Choose the longest chain that includes the functional group.
- Assign locants to give the lowest numbers to key groups and substituents.
- Use alphabetical order for naming multiple substituents.
The correct IUPAC names for the given compounds are methyl propanoate and 3-methyl-2-butanone.