How can I convert the bond-line structure of 2-methylhexane to a Newman projection viewed along the C3-C4 bond?

1 Answer
Jun 18, 2015

Answer:

You follow a series of steps.

Explanation:

Step 1. Draw the structure of 2-methylhexane.

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Step 2. Convert to a wedge-dash structure at #"C-3"# and #"C-4"#.

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Step 3. Identify the groups on #"C-3"# and #"C-4"#.

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

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

The groups on #"C-3"# are #"H"#, #"H"#, and #"CH(CH"_3)_2#. Those on #"C-4"# are #"H"#, #"H"#, and #"CH"_3"CH"_2#.

Step 4. Draw a template for a Newman projection.

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

View the molecule from the upper right.

The groups on #"C-3"# go on the front carbon atom. Put the #"CH(CH"_3)_2#group on the bottom. The two #"H"# atoms go on the other bonds.

The groups on #"C-4"# go on the back carbon. The bulky #"CH"_3"CH"_2# group goes on the top, and the two #H# atoms go on the other bonds.

enter image source here

This is the most stable conformer. It has the bulky isopropyl group anti to an ethyl group.