Q5 · CSIR NET Chemistry, June 2019
Paper: CSIR NET June 2019 · Subject: Organic Chemistry · Chapter: General Organic Chemistry · Topic: General Organic Chemistry – General · Marks: 2 · Difficulty: Medium
In the following equilibrium, conformer B is more stable than A when R is
A


(a)Me
(b)F
(c)Cl
(d)OMe
Answer
Answer: B ✓ checked by 4AB · confidence medium
Explanation
For trans-1,4-disubstituted cyclohexanes small electronegative groups such as F favour the diaxial conformer B. Axial C–F bonds gain σ(C–H) → σ*(C–F) hyperconjugation and the dipoles cancel, whereas Me, Cl and OMe prefer diequatorial (b).
Study loop for General Organic Chemistry