Question

I.U.P.A.C. name of the following compound is

• A. 4-bromo-2-ethyl-2,5-dimethylheptane
• B. 5-bromo-3,3,6-trimethyloctane
• C. 3-bromo-2,5-diethyl-5-methylhexane
• D. 4-bromo-3,6,6-trimethyloctane

Hint:

Always select the longest carbon chain and give substituents the lowest possible locant numbers.

Answer 1

The Correct Option is D

Step 1: Identification of longest carbon chain.
The longest continuous carbon chain in the given structure contains eight carbon atoms, hence the parent hydrocarbon is octane.

Step 2: Numbering of the carbon chain.
Numbering is done from the end nearest to the substituents to give the lowest set of locants.

Step 3: Identification of substituents.
There is one bromo group at carbon 4 and three methyl groups at carbons 3 and 6 (two methyl groups at carbon 6).

Step 4: Naming of the compound.
Arranging substituents in alphabetical order and applying locants, the correct IUPAC name is 4-bromo-3,6,6-trimethyloctane.