Arrange the following alkyl halides in order of increasing reactivity towards $SN^1$ reaction.
(A) $(CH_3)_3C-I$
(B) $(CH_3)_3C-F$
(C) $(CH_3)_3C-Br$
(D) $(CH_3)_3C-Cl$
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → (B), (D), (C), (A)
SN1 rate depends mainly on leaving group ability (I⁻ > Br⁻ > Cl⁻ > F⁻).
All compounds form the same tert-butyl carbocation, so only the halide matters.
Increasing reactivity:
$\text{(CH₃)₃C–F} < \text{(CH₃)₃C–Cl} < \text{(CH₃)₃C–Br} < \text{(CH₃)₃C–I}$
Correct option: (B), (D), (C), (A)