Which of the following represents a correct ring-flipped chair conformation of ${\mathrm{cyclohexane}}_{}$ with a methyl group at carbon $1$ in the axial position and a bromine at carbon $2$ in the equatorial position?

• A. Both methyl at carbon $1$ and bromine at carbon $2$ become axial after the ring flip.
• B. Both methyl at carbon $1$ and bromine at carbon $2$ become equatorial after the ring flip.
• C. Methyl at carbon $1$ becomes equatorial and bromine at carbon $2$ becomes axial after the ring flip.
• D. Methyl at carbon $1$ remains axial and bromine at carbon $2$ remains equatorial after the ring flip.

Answer: (C)

Verified step by step guidance

1. Recall that a ring flip in cyclohexane interconverts axial and equatorial positions: all axial substituents become equatorial, and all equatorial substituents become axial.
2. Identify the initial positions of the substituents: the methyl group is at carbon 1 in the axial position, and the bromine is at carbon 2 in the equatorial position.
3. Apply the ring flip rule: the methyl group at carbon 1, initially axial, will become equatorial after the flip.
4. Similarly, the bromine at carbon 2, initially equatorial, will become axial after the flip.
5. Conclude that the correct ring-flipped chair conformation has the methyl group at carbon 1 in the equatorial position and the bromine at carbon 2 in the axial position.