Reactions of carbonyl compounds, which include aldehydes and ketones, are primarily characterized by their ability to undergo nucleophilic addition due to the electrophilic nature of the carbonyl carbon. In these reactions, nucleophiles attack the carbonyl carbon, leading to the formation of tetrahedral intermediates. Common reactions include the addition of Grignard reagents, which convert carbonyls into alcohols, and the formation of hemiacetals and acetals when carbonyls react with alcohols. Additionally, carbonyl compounds can participate in oxidation and reduction reactions; aldehydes can be oxidized to carboxylic acids, while both aldehydes and ketones can be reduced to their corresponding alcohols. Other notable reactions include the Cannizzaro reaction for aldehydes lacking α-hydrogens, and condensation reactions such as aldol condensation, which involve the formation of β-hydroxy carbonyl compounds. Overall, the reactivity of carbonyl compounds is central to many organic synthesis pathways.
What is the primary type of reaction that carbonyl compounds undergo?
Carbonyl compounds primarily undergo nucleophilic addition reactions due to the electrophilic nature of the carbonyl carbon.
How do aldehydes and ketones differ in their reactivity towards oxidation?
Aldehydes are more easily oxidized to carboxylic acids, while ketones are generally resistant to oxidation under mild conditions.
What is the product formed when a carbonyl compound reacts with a Grignard reagent?
When a carbonyl compound reacts with a Grignard reagent, it forms an alcohol after subsequent hydrolysis of the resulting alkoxide intermediate.
What is the Cannizzaro reaction, and which carbonyl compounds participate in it?
The Cannizzaro reaction involves the disproportionation of aldehydes that lack α-hydrogens in the presence of a strong base, resulting in the formation of an alcohol and a carboxylic acid.
What happens when an aldehyde reacts with Tollen's reagent?
When an aldehyde reacts with Tollen's reagent, it is oxidized to a carboxylic acid, and the reagent is reduced to metallic silver, resulting in a silver mirror effect.
What type of reaction do carbonyl compounds primarily undergo?
a) Elimination
b) Nucleophilic addition
c) Substitution
d) Rearrangement
Answer: b) Nucleophilic addition
Which reagent is commonly used to oxidize aldehydes to carboxylic acids?
a) Sodium borohydride
b) Tollen's reagent
c) Grignard reagent
d) Hydrogen gas
Answer: b) Tollen's reagent
What is the product of the reaction between an aldehyde and a Grignard reagent?
a) Ketone
b) Alcohol
c) Acetal
d) Hemiacetal
Answer: b) Alcohol
Which of the following carbonyl compounds can undergo the Cannizzaro reaction?
a) Acetaldehyde
b) Benzaldehyde
c) Propanone
d) Butanone
Answer: b) Benzaldehyde
What is formed when an aldehyde reacts with alcohol in the presence of an acid catalyst?
a) Ketone
b) Hemiacetal
c) Carboxylic acid
d) Aldol
Answer: b) Hemiacetal