Chemistry - GOC Question with Solution | TestHub

The para isomer $\mathrm{I}$ permits donor-to-acceptor conjugation from ${\mathrm{NMe}}_2$ through the ring to ${\mathrm{NO}}_2$. The meta isomer $\mathrm{II}$ lacks that direct resonance path. In ortho isomer $\mathrm{III}$, crowding reduces planarity and inhibits resonance. The intended order is $\mathrm{I}$ > $\mathrm{II}$ > $\mathrm{III}$.