NucleophilicityHardQuestion 730012
Question
In polar aprotic solvents (e.g., DMSO), the nucleophilicity order of halide ions is:
- AI⁻ > Br⁻ > Cl⁻ > F⁻
- BF⁻ > Cl⁻ > Br⁻ > I⁻Correct
- CAll equal
- DF⁻ > I⁻ > Cl⁻ > Br⁻
Correct answer
F⁻ > Cl⁻ > Br⁻ > I⁻
Explanation
Polar aprotic solvents do not strongly hydrogen-bond to anions, so halide nucleophilicity broadly follows basicity: F⁻ > Cl⁻ > Br⁻ > I⁻. In polar protic solvents, strong solvation reverses this order.