MCAT Organic Chemistry Review

Carboxylic Acid Derivatives

Practice Questions

1.    Which of the following would be the best method of producing methyl propanoate?

1.    Reacting propanoic acid and methanol in the presence of a mineral acid

2.    Reacting methanoic acid and propanol in the presence of a mineral acid

3.    Reacting propanoic anhydride with an aqueous base

4.    Reacting propanoic acid with an aqueous base

2.    What would be the product(s) of the reaction below?

1.   

2.   

3.   

4.   

3.    Which of the following undergoes a Fischer esterification most rapidly?

1.   

2.   

3.   

4.   

4.    Each of the acyl compounds listed below contains a six-membered ring EXCEPT:

1.    δ-lactam.

2.    cyclohexane carboxylic acid.

3.    γ-butyrolactone.

4.    the anhydride formed from intramolecular ring closure of pentanedioic acid.

5.    Which of the following would be most reactive toward nucleophiles?

1.    Propyl ethanoate

2.    Propanoic acid

3.    Propanamide

4.    Propanoic anhydride

6.    How might succinic anhydride, shown below, be formed from succinic acid (butanedioic acid)?

1.    Catalytic acid

2.    Catalytic base

3.    Heat

4.    Oxidation

7.    Which of the following would react most readily with a carboxylic acid to form an amide?

1.    Methylamine

2.    Triethylamine

3.    Diphenylamine

4.    Ethylmethylamine

8.    If propanamide were treated with water, what product(s) would be observed?

1.    Propanamide

2.    Propanoic acid

3.    Equal concentrations of propanamide and propanoic acid

4.    Propyl propanoate

9.    β-lactams are:

1.    cyclic forms of the least reactive type of carboxylic acid derivative.

2.    more reactive than their straight-chain counterparts.

3.    molecules with high levels of ring strain.

1.    I only

2.    II only

3.    II and III only

4.    I, II, and III

10.The acid-catalyzed conversion of propyl ethanoate to benzyl ethanoate is likely:

1.    reduction.

2.    hydrolysis.

3.    transesterification.

4.    oxidation.

11.The reaction shown, which is important to breakdown of polypeptides, would be favored under what conditions?

1.    Mild heat

2.    Acid environment

3.    Anhydrous environment

4.    Nonpolar solvent

12.A positive charge on the molecule shown would have greater stability than a positive charge on a straight-chain alkane version of the same molecule. What property most explains this effect?

1.    Steric hindrance

2.    Nitrogen electronegativity

3.    Induction

4.    Conjugation

13.The molecule shown is:

1.    synthesizable from a γ-hydroxycarboxylic acid.

2.    a lactone.

3.    a form of an ester.

1.    I only

2.    I and II only

3.    II and III only

4.    I, II, and III

14.Which reactant could be combined with butanol to form butyl acetate?

1.    (CH3CO)2O and catalytic acid

2.    (CH3CH2CO)2O and catalytic acid

3.    CH3CH2CONH2 and catalytic acid

4.    CH3CONH2 and catalytic acid

15.Why should esterification reactions NOT be carried out in water?

1.    Carboxylic acids, from which esters are made, are generally insoluble in water.

2.    The polar nature of water overshadows the polar nature of the leaving group.

3.    The extensive hydrogen bonding of water interferes with the nucleophilic addition mechanism.

4.    Water molecules would hydrolyze the desired products back into the parent carboxylic acid.

PRACTICE QUESTIONS