The correct IUPAC name of the following organic compound is
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → 4-Bromo-3-methylheptanal
Step-by-Step IUPAC Naming
To name this organic compound correctly, we follow standard IUPAC nomenclature rules:
Identify the Principal Functional Group:
The molecule contains an aldehyde group ($-CHO$) at the end of the chain. This group takes the highest priority and defines the suffix as "-al".
Determine the Longest Carbon Chain:
Find the longest continuous carbon chain that includes the aldehyde carbon.
- The chain starts at the carbonyl carbon (C1).
- Following the path through the substituents, the chain contains 7 carbons in total.
- A 7-carbon alkane is "heptane," which becomes "heptanal" due to the aldehyde.
Number the Parent Chain:
Start numbering from the aldehyde carbon as C1 to give the principal functional group the lowest possible number:
- C1: Carbonyl carbon ($-CHO$).
- C2: $CH_2$ group.
- C3: Carbon attached to the methyl group ($CH_3$).
- C4: Carbon attached to the bromine atom ($Br$).
- C5, C6, C7: Remaining carbons of the propyl tail.
Identify and Position Substituents:
- There is a methyl group located at position 3.
- There is a bromo group located at position 4.
Assemble the Name Alphabetically:
Substituents are listed in alphabetical order (B for bromo comes before M for methyl):
- 4-bromo + 3-methyl + heptanal = 4-bromo-3-methylheptanal.