Rank the following compounds in order of increasing reactivity in electrophilic aromatic substitution.

Question

Quizplus · Accepted Answer

The reactivity of an aromatic compound towards electrophilic substitution depends on the availability of electrons on the ring. The more electron-donating groups (e.g. -NH2, -OH) the higher the reactivity. Conversely, electron-withdrawing groups (e.g. -NO2, -CHO) decrease the reactivity. In this case, compound II has a strong electron-donating group (-NH2) which makes it the most reactive. Compound I has a weak electron-donating group (-OH) which makes it less reactive than II but more reactive than IV and III. Compound IV has a weak electron-withdrawing group (-Cl) which reduces its reactivity. Compound III has a strong electron-withdrawing group (-NO2) which makes it the least reactive of all. Therefore, the correct order of increasing reactivity is II < I < IV < III, and the answer is B.

Rank the Following Compounds in Order of Increasing Reactivity in Electrophilic