Question

The IUPAC name of the following compound is:

• A. 1-Bromo-2-ethyl cyclohex-1-en-6-one
• B. 1-Bromo-6-ethyl cyclohex-1-en-2-one
• C. 2-Bromo-3-ethyl cyclohex-2-en-1-one
• D. 2-Bromo-1-ethyl cyclohex-1-en-3-one

Hint:

Always number the ring to give the carbonyl the lowest locant, then assign locants to substituents in alphabetical order if necessary.

Answer 1

The Correct Option is C

Step 1: Determining the parent structure.
The core ring is cyclohexene bearing a ketone group at position 1.

Step 2: Ring numbering priority.
Number the ring to assign the carbonyl carbon the lowest possible locant (1).

Step 3: Substituent positions.
Bromine is attached at carbon 2, and the ethyl group is at carbon 3.

Step 4: Assembling the full name.
Combining substituents with the parent yields: 2-Bromo-3-ethyl cyclohex-2-en-1-one.

Step 5: Final conclusion.
Option (3) is correct.