Question

Using Newman projections, draw the most stable conformer for each of the following:

a. 3-methylpentane, viewed along the C-2 - C-3bond

b. 3-methylhexane, viewed along the C-3 - C-4bond

c. 3,3-dimethylhexane, viewed along the C-3 - C-4bond

Short answer

The most stable structures are those which have less gauche interactions. The structures are,

Step-by-step solution

Subpart (a) Structural representation of Newman projection of 3-methylpentane, viewed along the C-2 -C-3  bond

The most stable structure of 3-methylpentane is shown below.

Subpart (b) Structural representation of Newman projection of 3-methylhexane, viewed along the C-3 - C-4  bond.

The most stable structure of 3-methylhexane is shown below.

Subpart (c) Structural representation of Newman projection of 3,3-dimethylhexane, viewed along the C-3 - C-4  bond

The most stable structure of 3,3-dimethylhexane is shown below.