Give IUPAC name of the following compound:

$CH_3-CH_2-CH_2-CH(Br)-CH(CH_3)-CH_2-CHO$

4-Bromo-3-methylheptanal

The correct answer is Option (4) → 4-Bromo-3-methylheptanal

To determine the IUPAC name, follow the systematic steps of nomenclature.

Step 1: Identify the principal functional group

The compound contains the –CHO group, which represents an aldehyde.

Aldehydes take priority in numbering and naming.

Thus, the parent suffix will be:

–al

Step 2: Identify the longest carbon chain containing –CHO

Counting from the aldehyde carbon:

CHO – CHâ‚‚ – CH(CH₃) – CH(Br) – CHâ‚‚ – CHâ‚‚ – CH₃

Total carbon atoms = 7

Therefore the parent chain is:

heptanal

Step 3: Number the chain

Numbering starts from the aldehyde carbon (C-1).

1 – CHO

2 – CHâ‚‚

3 – CH(CH₃)

4 – CH(Br)

5 – CHâ‚‚

6 – CHâ‚‚

7 – CH₃

Step 4: Identify substituents

Substituents present:

• Methyl group at C-3
• Bromo group at C-4

Step 5: Arrange substituents alphabetically

Substituents are written in alphabetical order:

Bromo before Methyl

Thus the name becomes:

4-Bromo-3-methylheptanal