Draw the important resonance contributors for both resonance-stabilized cations (in brackets) in the mechanism for acid-catalyzed hydrolysis of an amide.

Show how the following ketones might be synthesized from the indicated acids, using any necessary reagents.

(a) propiophenone from propionic acid (using Friedel–Crafts acylation)

Propose a mechanism for the hydrolysis of N,N-dimethylacetamide

(a) under basic conditions.

Propose a mechanism for the hydrolysis of N,N-dimethylacetamide

(b) under acidic conditions.

Propose a mechanism for the basic hydrolysis of benzonitrile to the benzoate ion and ammonia.

The mechanism for acidic hydrolysis of a nitrile resembles the basic hydrolysis, except that the nitrile is first protonated, activating it toward attack by a weak nucleophile (water). Under acidic conditions, the proton transfer (tautomerism) involves protonation on nitrogen followed by deprotonation on oxygen. Propose a mechanism for the acid-catalyzed hydrolysis of benzonitrile to benzamide.

In which step(s) of the hydride reduction of an ester does the compound undergo reduction? (Hint: Count the bonds to oxygen.)

Propose a mechanism for the reduction of octanoyl chloride by lithium aluminum hydride.

Draw a mechanism for the acidic hydrolysis of the magnesium salt shown below to acetophenone.

Draw a mechanism for the reaction of propanoyl chloride with 2 moles of phenylmagnesium bromide.

Show how you would add a Grignard reagent to an ester or a nitrile to synthesize

(a) 4-phenylheptan-4-ol.

Show how you would add a Grignard reagent to an ester or a nitrile to synthesize

(b) heptan-4-ol.

Show how you would add a Grignard reagent to an ester or a nitrile to synthesize

(c) pentan-2-one.

Show how Friedel–Crafts acylation might be used to synthesize the following compounds.

a. acetophenone

Show how Friedel–Crafts acylation might be used to synthesize the following compounds.

b. benzophenone

Show how Friedel–Crafts acylation might be used to synthesize the following compounds.

c. n-butylbenzene

Show how you would use anhydrides to synthesize the following compounds. In each case, explain why an anhydride might be preferable to an acid chloride.

(a) n-octyl formate

(b) n-octyl acetate

Show how you would use anhydrides to synthesize the following compounds. In each case, explain why an anhydride might be preferable to an acid chloride.

(c) phthalic acid monoamide 

(d) succinic acid monomethyl ester

Suggest the most appropriate reagent for each synthesis, and explain your choice.

(a)

Suggest the most appropriate reagent for each synthesis, and explain your choice.

(b)

Suggest the most appropriate reagent for each synthesis, and explain your choice.

(c)

Suggest the most appropriate reagent for each synthesis, and explain your choice.

(d)

Show how you would synthesize each compound, starting with an ester containing no more than eight carbon atoms. Any other necessary reagents may be used.

(a) Ph₃C–OH

(b) (PhCH₂)₂CHOH

(c) PhCONHCH₂CH₃

Show how you would synthesize each compound, starting with an ester containing no more than eight carbon atoms. Any other necessary reagents may be used.

(d) Ph₂CHOH

(e) PhCH₂OH

(f) PhCOOH

Show how you would synthesize each compound, starting with an ester containing no more than eight carbon atoms. Any other necessary reagents may be used.

(i) HO–(CH₂)₈–OH

Show how you would accomplish the following synthetic transformations. You may use any necessary reagents.

(a) N-ethylbenzamide → benzylethylamine

(b) ethyl benzoate → N-ethylbenzamide

Show how you would accomplish the following synthetic transformations. You may use any necessary reagents.

(c) pyrrolidine → N-acetylpyrrolidine

(d) γ-aminobutyric acid → pyrrolidine

Show how you would accomplish the following syntheses using amides as intermediates. You may use any necessary reagents.

(a) benzoic acid → benzyldimethylamine

(b) pyrrolidine → N-ethylpyrrolidine

(c) cyclopentanecarboxylic acid → cyclopentanecarbonitrile

Show how you would convert the following starting materials to the indicated nitriles:

(a) phenylacetic acid → phenylacetonitrile

Show how you would convert the following starting materials to the indicated nitriles:

(b) phenylacetic acid → 3-phenylpropionitrile