# What are the steps to convert Newman projections to bond line notations?

Aug 13, 2015

You look for the longest chain, then you add the substituents.

#### Explanation:

Here is the Newman projection of a hydrocarbon. What is its bond-line notation?

(from people.bethelks.edu)

Step 1. Find the longest continuous chain of carbon atoms.

There is one $\text{C}$ atom at the centre of the circle and a second one hidden at the back of the circle.

A methyl group off the back adds a third $\text{C}$ atom.

On the front carbon, the ethyl group has the longest chain, for another two $\text{C}$ atoms.

We draw a 5-carbon chain.

(from opsin.ch.cam.ac.uk)

Step 2. Locate the substituents.

Let's call the terminal $\text{C}$ of the ethyl group $\text{C-1}$.

Then the front carbon in the circle is $\text{C-3}$ and the hidden carbon is $\text{C-4}$.

$\text{C-3}$ has a methyl group attached, while $\text{C-4}$ has only $\text{H}$ atoms.

So we have a 5-carbon chain with a methyl group at $\text{C-3}$.

(from opsin.ch.cam.ac.uk)

And we have our bond-line structure.