Question

What is the IUPAC name of mesityl oxide?

• A. 4-Methylbenzaldehyde
• B. 2-Bromohexan-3-one
• C. 4-Methylpent-3-en-2-one
• D. 1-Phenylbutan-2-one

Hint:

Always number the carbon chain to give the carbonyl group the lowest possible locant.

Answer 1

The Correct Option is C

Step 1: Identify the structure of mesityl oxide.
Mesityl oxide is an \(\alpha,\beta\)-unsaturated ketone formed by aldol condensation of acetone.
Step 2: Assign IUPAC name.
The longest carbon chain contains five carbon atoms with a double bond at position 3 and a ketone group at position 2, along with a methyl substituent at position 4.
Step 3: Conclusion.
Hence, the IUPAC name of mesityl oxide is 4-Methylpent-3-en-2-one.