For menthol, (1R,2S,5R)-2-isopropyl-5-methylcyclohexan-1-ol, in its preferred chair conformation, which statements are correct?

AThe enantiomer, (1S,2R,5S), also has all three substituents equatorial in its preferred chair
BThe OH and isopropyl groups are on opposite faces of the ring (trans)
CThe OH and CH $_{3}$ groups are on opposite faces of the ring (trans)
DAll three substituents (OH, isopropyl, CH $_{3}$ ) are equatorial

Answer: A, B, D

In menthol the up/down pattern is OH up, iPr down, CH

_{3}

up (CIP check): OH/iPr are trans (1,2 e,e), OH/CH

_{3}

are cis (1,3 e,e), and iPr/CH

_{3}

are trans (1,4 e,e). Hence all three are equatorial and the third statement of cis OH/CH

_{3}

is the false one. The enantiomer has the same relative configuration with mirrored geometry, so it is also all-equatorial.