# Question #c241d

Dec 9, 2017

Got model set....?

#### Explanation:

When we draw a Newmann projection, we look DOWN a $C - C$ bond axis..... And in pentane there are 4 such $C - C$ bond axes. So we would have to consider each bond in isolation....where each bears TWO $C - H$ bonds, and the third spoke of the wheel on one carbon is the alkyl residue....

For more details see ....$\text{Newman, M. S. A notation for the study of certain}$
$\text{stereochemical problems. }$J. Chem. Educ. 1955 , 32 , 344-347.

Your librarian will certainly be able to get this for you.

Of course this is for butane, not methyl pentane....but it is easier to work and draw from a model.