Which of the following alkyl halides undergoes the fastest base-induced dehydrohalogenation?

Options

A. `t`-Butyl bromide
B. Isobutyl bromide
C. `iso`-Butyl iodide
D. `t-`Butyl iodide

Answer

D

Explanation

In both `E2` and `E1` eliminations, iodides are most reactive due to the weakest `C-I` bond. In `E2` elimination, `3^(@)RX` is the most reactive as it forms the most substituted transition state while in `E1` elimination, `3^(@)RX` is the most reactive as it forms the most stable tertiary carbocation.