Question

Which is the most stable conformational isomer of cis-1-bromo-2-chlorocyclohexane ?

• A.
• B.
• C.
• D.

Answer 1

The correct option is D

In given compound, the two halide groups are in cis position in C1 and C2 position. So the possible cis isomer chair form will be two.
1. Br at axial position and Cl at equatorial position
2. Cl at axial position and Br at axial position.

Larger size group sholud be at equatorial position to reduce the 1, 3 diaxial interaction.
Hence, Br at equatorial position and Cl at axial position is the stable conformational isomer of the given compound.
Thus, option (d) is correct.