In a substituted cyclohexane where a large substituent is present in the equatorial position, what is the likely impact on the molecule's stability when the ring undergoes flipping?

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In a cyclohexane, substituents in the equatorial position are far from the ring’s interior, so they experience little steric clash and the chair is stable. When the ring flips, the equatorial substituent moves to the axial position, bringing it close to the other axial hydrogens on the same side of the ring. This proximity creates 1,3‑diaxial interactions that raise the energy of the flipped chair, making it less stable. For example, a tert‑butyl group in the equatorial site will feel strong steric strain if it becomes axial during a flip, so the molecule prefers to stay in the conformation that keeps the bulky group equatorial. Thus, the presence of a large equatorial substituent makes the flipped chair significantly less stable than the original conformation.

In a substituted cyclohexane where a large substituent is present in the equatorial position, what is the likely impact on the molecule's stability when the ring undergoes flipping?

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