chapter 6: aldehydes and ketones I

What can aldehydes be oxidized to?

Aldehydes can be oxidized to carboxylic acids.

What oxidizing agents can oxidize aldehydes?

KMnO4, CrO3, Ag₂O, H₂O₂

How can aldehydes be reduced?

Aldehydes can be reduced to primary alcohols using hydride reagents.

What hydride reagents reduce aldehydes?

LiAlH₄ and NaBH₄

What happens to ketones during oxidation?

Ketones cannot be further oxidized.

How can ketones be reduced?

Ketones can be reduced to secondary alcohols using hydride reagents.

What is the structure suffix for aldehydes?

Aldehydes have the suffix -al.

What is the structure suffix for ketones?

Ketones have the suffix -one.

What reactions do carbonyls undergo?

Carbonyls undergo nucleophilic addition reactions.

What contributes to the higher boiling points of aldehydes and ketones?

Higher boiling points are due to dipole interactions.

What are hemiacetals and acetals?

Hemiacetals and acetals are formed from reactions involving carbonyls.

What are aldehydes and their characteristics?

Terminal functional groups with a carbonyl ((C=O)) bonded to at least one hydrogen. Nomenclature uses the suffix -al and the prefix oxo-.

How are aldehydes indicated in rings?

They are indicated by the suffix -carbaldehyde.

What are ketones and their characteristics?

Internal functional groups with a carbonyl bonded to two alkyl chains. Nomenclature uses the suffix -one and the prefix oxo- or keto-.

What dictates the reactivity of a carbonyl ((C=O))?

The polarity of the double bond; the carbon has a partial positive charge making it electrophilic.

Why do carbonyl-containing compounds have higher boiling points?

Due to dipole interactions; they are higher than equivalent alkanes but lower than alcohols (which have hydrogen bonding).

How are aldehydes and ketones commonly produced?

By the oxidation of primary and secondary alcohols, respectively.

What is needed to synthesize aldehydes without over-oxidation?

Weaker, anhydrous oxidizing agents like Pyridinium chlorochromate (PCC).

What oxidizing agents are used for ketones?

Dichromate, chromium trioxide, or PCC.

What occurs during a nucleophilic addition reaction?

A nucleophile attacks the carbonyl carbon, forming a bond and pushing electrons to the oxygen.

What happens if there's no good leaving group in carbonyl reactions?

The carbonyl remains open and is protonated to form an alcohol.

What do hydration reactions form when water adds to a carbonyl?

A geminal diol.

What is formed when one equivalent of alcohol reacts with an aldehyde?

A hemiacetal.

What is formed when one equivalent of alcohol reacts with a ketone?

A hemiketal.

What is produced when another equivalent of alcohol reacts with a hemiacetal?

An acetal.

What is produced when another equivalent of alcohol reacts with a hemiketal?

A ketal.

What do nitrogen derivatives form when they react with carbonyls?

They form imines, oximes, hydrazones, and semicarbazones.

What can imines tautomerize to form?

Enamines.

What happens when hydrogen cyanide reacts with carbonyls?

It forms cyanohydrins.

what are aldehydes oxidized to

carboxylic acids

what are aldehydes reduced to

primary alcohols