Chapter 8, Problem 8.45P

Interpretation Introduction

Interpretation:

The cis isomer of $\text{1-bromo-4-tert-butylcyclohexane}$ undergoes $\text{E2}$ elimination about $1,000$ times faster than the trans isomer is to be explained.

Concept introduction:

The $\text{E2}$ reactions are favored by the substrate conformation where the eliminating groups (leaving group $\text{L}$ and $\text{H}$) are anti to each other. The bulkier groups prefer equatorial position for the more stable cyclohexane chair conformation.