Medicinal & Pharmaceutical Chemistry: Aldehydes and Ketones Part 2

These flashcards cover key concepts from the lecture on aldehydes and ketones, including their reactions, structures, and significance in medicinal chemistry.

What is the outcome of an aldol reaction?

The formation of an aldol from aldehydes or ketones.

What is required for an aldol reaction to occur?

At least one hydrogen on the alpha carbon and a strong base.

How does collagen structure relate to aldol reactions?

Collagen has intramolecular cross-links formed by aldol condensations.

What is the primary reducing agent in the reduction of aldehydes and ketones?

NADH or NADPH.

What does the Tollens' reagent test for?

It distinguishes aldehydes from ketones by oxidizing aldehydes.

How does Fehling's solution differentiate between aldehydes and ketones?

It oxidizes aldehydes to carboxylic acids, producing a brick red precipitate.

What is the result of oxidizing a primary alcohol?

It yields an aldehyde and can further oxidize to a carboxylic acid.

What stabilizes an enolate during deprotonation?

Resonance.

What is a characteristic of the α-carbon in carbonyl compounds?

The hydrogen on the α-carbon is weakly acidic.

What happens during the dehydration of aldol products?

It can lead to the formation of enals at higher temperatures.

How is the oxidation level of carbon determined?

By counting the number of bonds between carbon and atoms other than hydrogen.

What is the main biochemical method for producing alcohols?

Reduction of aldehydes or ketones.

What happens when a ketone is oxidized with Tollens' reagent?

No reaction occurs; ketones are not oxidized.

What is the mechanism of nucleophilic addition in the aldol reaction?

An enolate ion acts as the nucleophile and reacts with a carbonyl compound.

What defines the structure of aldehydes?

They have at least one hydrogen atom bonded to the carbonyl carbon.

Why is the presence of hydrogen on the α-carbon significant?

It allows the carbon to participate in aldol condensation.

What is produced from the dehydration of an aldol product?

An enal.

What role does Lysyl Oxidase play in collagen structure?

It oxidizes lysine side chains to aldehydes, forming cross-links.

Can ketones be oxidized to carboxylic acids?

No, ketones cannot be oxidized by Tollens' or Fehling's reagents.

What type of alcohol is produced when an aldehyde is reduced?

Primary alcohol.

What is a common oxidizing agent used to convert primary alcohols to aldehydes?

Pyridinium chlorochromate (PCC).

What is the effect of increased cross-linking in collagen?

It enhances the mechanical strength of collagen.

Aldehydes contain which functional group?

The carbonyl group (C=O) at the end of a carbon chain.

How does an increase in oxidation level during a reaction correlate?

It corresponds to an oxidation reaction.

What type of reaction does an enolate undergo?

Nucleophilic addition to a carbonyl compound.

What distinguishes aldol reactions from other reactions?

They involve the formation of β-hydroxy carbonyl compounds.

What can be prepared from the oxidation of secondary alcohols?

Ketones.

What does the term 'aldol' refer to?

A compound formed from an aldol reaction; it contains both aldehyde and alcohol functional groups.

What is the difference in the reactions of aldehydes and ketones with Fehling's solution?

Aldehydes are oxidized; ketones are not.

What structural feature is characteristic of ketones?

They have two carbon groups attached to the carbonyl carbon.

What type of cross-link is formed from aldol condensation in collagen?

Intramolecular and intermolecular cross-links.

What is formed by the reaction of aldehydes with Tollens' reagent?

Carboxylic acid and metallic silver.

What structural modifications occur in collagen due to aldol reactions?

Formation of cross-links between tropocollagen molecules.

What can trigger the dehydration of an aldol product?

Increased temperature or enzymatic activity.

In a carbonyl compound, which carbon is referred to as the volatility center?

The carbonyl carbon.

What stipulates the requirement for a carbon to be oxidized?

Increased bonds to more electronegative atoms.

What does the term 'nucleophilic addition' describe in the context of aldehydes and ketones?

The addition of a nucleophile to a carbonyl carbon.

Aldol condensation involves which types of compounds?

Aldehydes and ketones.

What is a key feature of the product from aldol condensation?

It typically has a β-hydroxy carbonyl structure.

What makes the hydrogen on the α-carbon (next to the carbonyl) slightly acidic?

Resonance stabilization of the resulting enolate.

What effect does a strong base have on aldehydes in an aldol reaction?

It promotes the formation of the enolate ion.

What is the outcome when aldehydes are treated with Fehling's solution?

A color change to brick red due to the formation of cuprous oxide.

What is the primary catalyst used in the aldol reaction?

A strong base, such as hydroxide ions.

How do you classify the oxidation levels of carbon based on bonds?

Higher oxidation levels correlate with more bonds to electronegative elements.

What product is formed when aldehydes react with reducing agents?

Primary alcohols.

In which part of the lecture are the oxidation and reduction reactions of aldehydes discussed?

Slides covering the reduction of aldehydes and ketones.

What is required for dehydration of the aldol product?

Higher temperatures or specific enzyme activity.

What defines a carbonyl compound?

A compound containing a carbon-oxygen double bond.

What is the significance of studying aldehydes and ketones in medicinal chemistry?

They are crucial in the synthesis of various pharmaceuticals.

What type of reaction occurs between compounds in aldol condensation?

Nucleophilic addition followed by elimination.

What does the silver mirror test detect?

The presence of aldehydes due to oxidation.

What occurs during the oxidation of ketones?

Ketones are not oxidized in standard tests.

What substance do reducing agents provide during reduction?

A hydride ion.

How are woody plants' cross-links formed?

Via aldol condensations involving lysine residues.

How can aldehydes and ketones be prepared from alcohols?

Through oxidation processes.

What type of functional transformation occurs for secondary alcohols during oxidation?

Conversion to ketones.

In the aldol reaction, what role does the enolate play?

It acts as a nucleophile for electrophilic attack.

What aspect of carbon atom oxidation is emphasized in the lecture?

Counting bonds to determine oxidation state.

What compound is formed when an enal results from aldol dehydration?

An unsaturated carbonyl compound.

How are collagen mechanical properties regulated?

By the extent of cross-linking through aldol reactions.

Who is the professor leading the MEDCHEM lecture?

Prof. Marc Devocelle.

What structural feature makes aldehydes distinct from ketones?

The presence of at least one hydrogen atom on the carbonyl carbon.

What educational resource is suggested for further reading on organic chemistry?

Organic Chemistry with Biological Applications by John McMurry.

What are the implications of knowing the oxidation level of a compound?

It helps to determine the possibility of reactions, like oxidation or reduction.