Final answer:
Toluene is ortho, para directing while trifluoromethylbenzene is meta directing due to the resonance structures of these compounds.
Step-by-step explanation:
Toluene is ortho, para directing while trifluoromethylbenzene is meta directing due to the resonance structures of these compounds.
In the case of toluene, the methyl group acts as an electron-donating group and stabilizes the positive charge on the intermediate carbocation in the ortho and para positions through resonance. This makes these positions more favorable for electrophilic substitution reactions.
On the other hand, in trifluoromethylbenzene, the trifluoromethyl group acts as an electron-withdrawing group and destabilizes the positive charge on the intermediate carbocation in the ortho and para positions. However, in the meta position, the positive charge is stabilized through resonance with the fluorine atoms. This makes the meta position more favorable for electrophilic substitution reactions.