Home > Organic Chemistry > Choosing between SN1 and SN2

Why do solvents with low dielectric constants favor SN2 reactions?

Answer 1

Solvents with low dielectric constants did not interfere the nucleophilic's attack, while the high dielectric constants solvent did it.

Since the SN2 reaction mechanism is concerted, nucleophilicity plays a crucial role. The polar solvent (high dielectric constants) dissolves (as solvent) nucleophiles with electropositive charges, resulting in a decrease in nucleophilicity.

By signing up, you agree to our Terms of Service and Privacy Policy

Answer 2

Ryan Andrews

Solvents with low dielectric constants favor SN2 reactions because they are less polar and weaken the ionic bonds in the reactants, facilitating the nucleophile's attack on the substrate. Additionally, low dielectric constant solvents reduce the solvation of ions, promoting the interaction between the nucleophile and the substrate.

By signing up, you agree to our Terms of Service and Privacy Policy

Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.