19. Reactions of Aromatics: EAS and Beyond

Provide the major organic product for the following reaction.

Explain why hydroxide ion catalyzes the reaction of piperidine with 2,4-dinitroanisole but has no effect on the reaction of piperidine with 1-chloro-2,4-dinitrobenzene.

In the context of nucleophilic aromatic substitution, why is the ${\mathrm{NO}}_2$ group considered a meta director when it comes to electrophilic aromatic substitution reactions?

Which of the following statements about nucleophilic aromatic substitution is true?

Provide the major organic product for the following reaction.

Propose mechanisms and show the expected products of the following reactions.

(a) 2,4-dinitrochlorobenzene + sodium methoxide (NaOCH₃)

(b) 2,4-dimethylchlorobenzene + sodium hydroxide, 350 °C

Show how the substituents containing the azo group (N=N) can facilitate both electrophilic and nucleophilic aromatic substitution.

(b)

(a) Propose a mechanism for the reaction of 2-bromopyridine with sodium amide to give 2-aminopyridine.

Draw resonance contributors for the carbanion that would be formed if meta-chloronitrobenzene were to react with hydroxide ion. Why doesn't the reaction occur?

Predict the products of the following nucleophilic aromatic substitution reactions.

(c)

Which of the following compounds is most likely to undergo nucleophilic aromatic substitution via the addition-elimination pathway? 

Propose a mechanism for the following reaction:

Using the given starting material, any necessary inorganic reagents and catalysts, and any carbon-containing compounds with no more than two carbons, indicate how each of the following compounds can be prepared:

b.

Show how the substituents containing the azo group (N=N) can facilitate both electrophilic and nucleophilic aromatic substitution.

(a)

Provide the structure of the product formed from the reaction of 1-bromo-2,4,6- trinitrobenzene with one equivalent of sodium methoxide.