Question

The IUPAC name of the following compound is: 

• A. 6-ethyl-2-methyldec-4-en-7-ol
• B. 2-methyl-6-ethyldec-4-en-7-ol
• C. 5-ethyl-9-methyldec-6-en-4-ol
• D. 9-methyl-5-ethyldec-6-en-4-ol

Hint:

Always number from the end nearest to the highest-priority group (here, the –OH). - Ensure correct locants for substituents and the double bond.

Answer 1

The Correct Option is C

Step 1: Longest Chain and Main Functional Group

• The parent chain has 10 carbons (dec).
• There is an alcohol (–OH) group, which gets priority in numbering.

Step 2: Numbering and Locating the Double Bond

• The OH ends up at C-4.
• The double bond is at C-6 (hence “dec-6-en-4-ol”).

Step 3: Substituents

• There is an ethyl group at C-5 and a methyl group at C-9.

Putting it all together, the correct IUPAC name is 5-ethyl-9-methyldec-6-en-4-ol.