Question

The rate constants for the bromination of several disubstituted stilbenes are given in the table below Given that the double bond of stilbene acts as the nucleophile, choose the reasonable explanations for the trend observed among the rate constants. Select all that apply. The nitro group is powerfully electron-withdrawing, via resonance which will reduce the nucleophilicity of the alkene pi bond. Methoxy group is a powerful activator, so its effect should be larger than the effect of a methyl group which is only weakly activating. A methyl group is strongly activating, so its effect should be smaller than the effect of a methoxy group. A chloro group withdraws electron density from the aromatic ring and the conjugated alkene pi bond. Chloro and nitro groups are deactivating groups. The Y substituent is near the alkene pi bond, so there could be a steric effect. The chloro and nitro groups are donating the electrons via resonance into the alkene pi bond, so the rate constant is smaller than the methoxy and methyl groups.

Answer 1

♡ The nitro group is powerfully election - withdrawing - Via resonance which will reduce the nucleo hili city of the alleme it bond. ♡ Methoxy group is a powerful activator, so its effect should be larger than the effect of a 1. methyl group which is only weak activating. O A methyl group is strongly activating, so its effect should be smaller than the [et a refox +- O A chloro group with draws electron density from the aromatic ring and the conjugated - athene T bondo o chloro and nitro groups are deactivating group.