Question 1

Which of the following statements best explains why aldehydes are generally more reactive than ketones toward nucleophilic addition reactions?

Accepted Answer

Aldehydes have only one alkyl group and one hydrogen, resulting in less steric hindrance and a more electrophilic carbonyl carbon.

Question 2

What is the major organic product when benzaldehyde reacts with methylamine under acidic conditions?

Accepted Answer

N-methylbenzaldimine (Schiff base)

Question 3

Which reagent is required for the Wittig reaction to convert a ketone into an alkene?

Accepted Answer

A phosphonium ylide

Question 4

Which of the following best describes the mechanism of acetal formation from an aldehyde and an alcohol?

Accepted Answer

Nucleophilic addition followed by elimination of water

Question 5

A carboxylic acid reacts with thionyl chloride ($$\mathrm{$$SOCl_2$$}). $$What is the major product?

Accepted Answer

Carboxylic acid chloride

Question 6

Which of the following carboxylic acid derivatives is most reactive toward hydrolysis under acidic conditions?

Accepted Answer

Acid chloride

Question 7

In the aldol condensation reaction, which intermediate is formed after the initial nucleophilic attack of the enolate on the carbonyl compound?

Accepted Answer

A beta-hydroxy carbonyl compound

Question 8

Which of the following statements about enolates is correct?

Accepted Answer

Enolates are formed by the deprotonation of the alpha hydrogen of a carbonyl compound.

Question 9

Which of the following is the correct product of the hydrolysis of an ester under basic conditions?

Accepted Answer

Alcohol and carboxylate ion

Question 10

A student attempts to synthesize an ester from a carboxylic acid and an alcohol. Which reagent is necessary to drive the reaction to completion?

Accepted Answer

A dehydrating agent such as concentrated $$\mathrm{H_2SO_4}$$

Question 11

Which of the following best explains why amides are less reactive than esters toward nucleophilic acyl substitution?

Accepted Answer

The nitrogen in amides donates electron density to the carbonyl carbon, stabilizing it.

Question 12

Which of the following reactions is used in the laboratory to convert a ketone into a secondary alcohol?

Accepted Answer

Reduction with $$\mathrm{$$NaBH_4$$}$$

Question 13

Which of the following is a key step in the mechanism of the Wittig reaction?

Accepted Answer

Formation of a betaine intermediate

Question 14

Which of the following statements about the hydrolysis of amides is correct?

Accepted Answer

Hydrolysis of amides requires more vigorous conditions than esters due to resonance stabilization.

Question 15

Which of the following is the correct product of an aldol condensation between acetone and benzaldehyde under basic conditions?

Accepted Answer

4-Phenyl-3-buten-2-one

Question 16

Which of the following best describes the role of acid in the formation of acetals from aldehydes?

Accepted Answer

Acid protonates the carbonyl oxygen, increasing electrophilicity and facilitating nucleophilic attack.

Question 17

Which of the following is the correct order of reactivity of carboxylic acid derivatives toward nucleophilic acyl substitution?

Accepted Answer

Acid chloride \u003e anhydride \u003e ester \u003e amide

Question 18

Which of the following is a common use of the aldol condensation in pharmaceutical synthesis?

Accepted Answer

Formation of carbon-carbon bonds to build complex drug molecules

Question 19

Which of the following statements about ester enolates is correct?

Accepted Answer

Ester enolates are commonly generated using strong bases such as $$\mathrm{LDA}.$$

Aldehydes, Ketones, Carboxylic Acids, and Derivatives: Structure, Reactivity, and Key Reactions

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