Question

Which among $\mathrm{MeX},{\mathrm{RCH}}_2\mathrm{X},{\mathrm{R}}_2\mathrm{CHX},{\mathrm{R}}_3\mathrm{CX}$ is most reactive towards S_N2 reaction?

Answer 1

S_N2 reaction

• S_N2 stands for Substitution nucleophilic bimolecular reaction.
• In this reaction, the rate of reaction depends upon the concentration of both reactants.
• It follows second-order kinetics.
• In this reaction, the formation of the bond and cleavage of the bond occurs simultaneously.
• The order of reactivity followed is Primary halide > Secondary halide > Tertiary halide.

Most reactive towards S_N2 reaction

• Because there are only three tiny hydrogen atoms in methyl halides$\left({\mathrm{CH}}_3\mathrm{X}\right)$, they react the fastest in S_N2 reactions.
• The reaction is as follows:-
• 
• Bulky groups inhibit approaching nucleophiles, tertiary halides are the least reactive.
• So, the most reactive towards S_N2 reaction is Methyl halide$\left(\mathrm{MeX}\right)$.