confirmational analysis of butane

Question 1

Butane (C4H10) has two distinct staggered
conformations, unlike ethane

Answer 1

• The terminal CH3
  groups can be gauche…
• anti

Question 2

Steric interaction between the gauche
methyl groups is called

Answer 2

gauche
interaction

Question 3

In the anti conformer, the CH3
groups

Answer 3

do not engage in
steric interactions with one another

Question 4

Staggered conformers are still energy

Answer 4

minima

Question 5

eclipsed conformers are still

Answer 5

maxima

Question 6

Anti or gauche? Which is lower in energy and why?

Answer 6

The anti conformer is lower in energy than the gauche conformer due to a destabilizing steric interaction in the latter

Question 7

Eclipsing CH3 groups

Answer 7

cause greater destabilization than
H-H or H-CH3
eclipsing