Question

How can I convert 2-methylhexane `C2-C3` bond from bond line notation to Newman projection?

Answer 1

You follow a sequence of steps.

Explanation:

Step 1. Draw the structure of 2-methylhexane.

Step 2. Convert to a wedge-dash structure at `"C-2"` and `"C-3"`.

Step 3. Identify the groups on `"C-2"` and `"C-3"`.

The main chain of hexane is the horizontal zig-zag line of carbon atoms.

`"C-1"` is on the right.

The groups on `"C-2"` are `"H"`, `"CH"_3`, and `"CH"_3`. Those on `"C-3"` are `"H"`, `"H"`, and `"CH"_3"CH"_2"CH"_2`.

Step 4. Draw a template for a Newman projection.

Step 5. Attach the groups to the carbons of your template.

View the molecule from the lower right.

The groups on `"C-2"` go on the front carbon atom. Put a `"CH"_3` group on the top. The other `"CH"_3` group goes on the left, and the `"H"` goes on the right.

The groups on `"C-3"` go on the back carbon. The bulky `"CH"_3"CH"_2"CH"_2` group goes on the bottom, and the `"H"` atoms go on the other bonds.

This is the most stable conformer. It has the bulky propyl group anti to a methyl group.