Aromatic Substitution Reactions

Step 1: Understanding the reactivity of the methoxy group.
The methoxy group ( ) is an electron-donating group, which activates the benzene ring, making the ortho- and para-positions more reactive towards electrophilic substitution reactions like nitration.
Step 2: The role of the bromine group.
Bromine ( ) is also an electron-donating group, but less so compared to methoxy. The presence of both methoxy and bromine on the ring causes the nitration to occur predominantly at the ortho- and para- positions relative to both groups.
Step 3: Resulting substitution products.
As a result, the nitro group ( ) is substituted at both the ortho- and para-positions relative to the methoxy group and bromine group on the benzene ring.
Conclusion:
Both the ortho- and para-positions to the methoxy group and bromine are activated, leading to substitution at these positions.

Step 1: Understand the reaction type.
This is a nucleophilic substitution reaction, where the methoxy group ( ) from the sodium methoxide ( ) replaces one of the chlorine atoms on the benzene ring.
Step 2: Methoxy group as a nucleophile.
The methoxy group ( ) is an electron-donating group and acts as a nucleophile. Under the reaction conditions (using ), the methoxy group replaces the chlorine atom in a nucleophilic substitution at the position that is ortho or para to the nitro group.
Step 3: Substitution outcome.
Since the methoxy group is nucleophilic and the chlorine is a leaving group, the substitution occurs at the available site (para to the nitro group), yielding the final product as .