1,3-Diaxial interaction

Definition

In organic chemistry, specifically in the context of cyclohexanes and their stereochemistry, 1,3-diaxial interactions are repulsive forces between axial substituents on a cyclohexane ring that are positioned on carbon atoms three positions apart (e.g., carbons 1 and 4). These interactions are a type of steric hindrance that affects the stability and conformational preferences of cyclohexanes.

Related terms

Cyclohexane chair conformation: A three-dimensional arrangement of atoms in a cyclohexane molecule that minimizes steric hindrance, resembling an armchair.

Axial position: In cyclohexane chair conformations, these are the positions projecting upward or downward from the plane of the ring, parallel to the ring's symmetry axis.

Equatorial position: In cyclohexane chair conformations, these refer to the positions extending outward from the plane of the ring, providing more space and thereby reducing steric hindrance compared to axial positions