Question

1. Overall why is the staggered conformation better than the eclipsed?

2. Why is the anti-conformation better than the gauche conformation?

3. Why is gauche better than eclipsed?

Answer 1

1. Staggered is more stable than eclipsed because a) Eclipsed has more steric hinderance than the staggered conformation becuase atoms are closer in Eclipsed. In staggered, presence of hyperconjugation makes molecule more stable.

2. Anti conformation is more stable because gauche has comparatively more steric hinderance than anti(staggered)

3. Eclipsed has more closeness between atoms and more steric hinderance as compared to Gauche conformation. So gauche is relatively more stable.

Generally, Staggered is more stable than Gauche, followed by Eclipsed conformation.