Question

Question 3. [time 4 + 8 = 12 minutes) (a) i. Both the regioselectivity and the rate of an electrophilic aromatic substitution are affected by the substituents already attached to the benzene ring. Some groups promote substitution at the ortho or para positions, while other groups increase substitution at the meta position. Explain the terms "resonance effect" and "inductive effect" of substituents (use words and schemes). ii. Explain, using words and schemes, how in electrophilic aromatic substitutions existing substituents direct a new incoming substituent. Hint: Discuss ortho/para and meta directing substituents and their role in stabilizing (or destabilizing) the intermediate o-complexes (or Wheland complexes). End of Section A

Answer 1

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