Question

Consider the following compounds:

The correct order of reactivity towards SN² reaction

Options

• I > III > II

• II > III > I

• II > I > III

• III > I > II

Answer 1

II > I > III

Explanation:

Chlorine's I effect attracts electrons, resulting in a tiny positive charge on the carbon bonded.
Compound 2 has the strongest I effect of chlorine, rendering it susceptible to the SN₂ reaction.
In compound 3, the strong I impact of chlorine is balanced by the resonance effect, allowing replacement at the o- and p- positions.
Compound 1 balances the negative effect of chlorine with a positive effect of the cycloalkyl group.