Question

Among the butane conformers, which occur at energy minima on a graph of potential energy versus dihedral angle?

• A. \( \text{Synperiplanar} \)
• B. \( \text{Antiperiplanar} \)
• C. \( \text{Gauche} \)
• D. \( \text{Eclipsed} \)

Hint:

In conformational analysis, the lowest energy structure corresponds to the most stable spatial arrangement of atoms.

Answer 1

The Correct Option is B

The antiperiplanar conformation of butane occurs at energy minima, where steric hindrance and torsional strain are minimized. In this conformation, bulky substituents are positioned opposite each other, reducing repulsive interactions. Gauche conformers have higher energy due to steric clash, and eclipsed conformations are at energy maxima.