# Influence of protic and aprotic solvents on SN reactions [closed]

How does protic and aprotic solvents influence reaction mechanism considering SN1 vs SN2?

• You will find your answer here and here Apr 6 '19 at 7:43

As you know, $$\mathrm{S_N1}$$ and $$\mathrm{S_N2}$$ reactions have different mechanisms. $$\mathrm{S_N1}$$ occurs in 2 steps: formation of a carbocation and addition of the nucleophile. However, $$\mathrm{S_N2}$$ has a one-step mechanism where the addition of the nucleophile and the elimination of the leaving group happen simultaneously.
A protic solvent would participate in hydrogen bonding with the nucleophile since it can easily share one proton. A solvent shell is thus formed around the nucleophile, making him less able to undergo a $$\mathrm{S_N2}$$ reaction.