Draw 2-ethyl-5-sec-butylheptane and what is the correct iupac name?

1 Answer
Aug 25, 2015

The correct IUPAC name is 4-ethyl-3,7-dimethylnonane.

Explanation:

The structure of 2-ethyl-5-sec-butylheptane is

StructureStructure

The 7-carbon chain is the horizontal zig-zag line.

The ethyl group is on "C-2"C-2, and the sec-butyl group is on "C-5"C-5.

But the longest continuous chain is the 9-carbon chain that runs from the top to the lower right.

We start numbering from the lower right, because that end is closer to more substituents — it gives us lower numbers.

There are methyl groups on "C-3"C-3 and on "C-7"C-7, and an ethyl group on "C-4"C-4.

The IUPAC name is therefore 4-ethyl-3,7-dimethylnonane.