Which is the correct order of the following alkyl halides for an $\mathrm{S}_{\mathrm{N}} 2$ reaction?
Which is the correct order of the following alkyl halides for an $\mathrm{S}_{\mathrm{N}} 2$ reaction?
$\mathrm{ii}>\mathrm{i}>\mathrm{iii}$
iii $>$ i $>$ ii
iii $>$ ii $>$ i
$\mathrm{ii}>\mathrm{iii}>\mathrm{i}$
Solution
Least substituted carbon atom ( $\alpha$ - carbon) gives rise to high reactivity towards $\mathrm{S}_{\mathrm{N}} 2$ reactions.
Thus, the corresponding reactivity order will be:
