19. Reactions of Aromatics: EAS and Beyond

Show how the following compounds can be prepared from benzene:

c.

Describe how 3-methyl-1-phenyl-3-pentanol can be prepared from benzene. You can use any inorganic reagents and solvents, and any organic reagents provided they contain no more than two carbons.

Benzene underwent a Friedel–Crafts acylation followed by a Wolff–Kishner reduction. The product gave the following 1H NMR spectrum. What acyl chloride was used in the Friedel–Crafts acylation?

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Beginning with benzene, synthesize the benzyl bromide shown.

Beginning with benzene, synthesize the following substituted benzenes. The ideal number of steps is indicated.

(d) 

FROM THE LITERATURE The following steps were used in the synthesis of the antimalarial thiaplakortone A. Identify the missing reagents, (a) and (b), 

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Provide the necessary reagents next to the arrows.

Phenolphthalein, a common nonprescription laxative, is also an acid–base indicator that is colorless in acid and red in base. Phenolphthalein is synthesized by the acid-catalyzed reaction of phthalic anhydride with 2 equivalents of phenol.

b. Propose a mechanism for the conversion of phenolphthalein to its red dianion in base.

c. Use resonance structures to show that the two phenolic oxygen atoms are equivalent (each with half a negative charge) in the red phenolphthalein dianion.

Show how you would use the Friedel–Crafts acylation, Clemmensen reduction, and/or Gatterman–Koch synthesis to prepare the following compounds:

g. n-butylbenzene

Show how you would use the Friedel–Crafts acylation, Clemmensen reduction, and/or Gatterman–Koch synthesis to prepare the following compounds:

h.

Describe two synthetic routes for the preparation of p-methoxyaniline from benzene.

Show how you would synthesize the following compounds, using the indicated starting materials.

(a) 3-phenylbutan-1-ol from styrene

The antioxidants BHA and BHT are commonly used as food preservatives. Show how BHA and BHT can be made from phenol and hydroquinone

Predict the major product at the end of each sequence.

(a)

Predict the major product at the end of each sequence.

(b)