Mcat Organic Chemistry Aldehydes And Ketones

Front 1

Addition Reactions of Aldehydes

Back 1

1. hydration
2. acetal and ketal formations
3. rxn with cyanohydrins
4. condensation w/ ammonia derivatives.

Front 2

Hydration of aldehydes and ketones

Back 2

1.in the presence of water, aldehydes and ketones form gem-diols, where H2O is the nucelophile
2. this slow rxn can be sped up by addition of an acid or base

Front 3

Acetal & Ketal Formation

Back 3

1. hemiacteal is formed from an aldehyde/ketone and an alcohol.
2. acetals are formed when another alcohol is added to the hemiacetal
3. rxn catalyzed by anhydrous acid & convertred back w/aqueous acid

Front 4

Formation of Cyanohydrins

Back 4

1.cyanide ion attacks the carbon atom on the carbonyl of an aldehyde or ketone
2. Cyanohydrins are unstable

Front 5

Condensation with Ammonia Derivatives

Back 5

1.Ammonia and its derivatives are nucleophiles.
2. Simplest form: Imine
3. Rxn can proceed to more compounds after LG leaves tet. intermediate

Front 6

Aldehydes oxidized to carboxylic acid

Back 6

Oxidation reagents used: KMnO4, CrO3, Ag2O, H2O2

Front 7

Aldehydes and Ketones oxidized to alcohols

Back 7

Use oxidation reagent LAH (or NaBH4 when milder conditions are needed)

Front 8

Two methods to reduce aldehydes and ketones to alkanes

Back 8

1. Wolff-Kishner Reduction
2. Clemmensen Reduction

Front 9

Wolff-Kishner Reduction

Back 9

1. only good when product is stable under basic conditions
Aldehyde/Ketone + H2NNH2-> hydrazone + base/heat -> alkane

Front 10

Clemmensen Reduction

Back 10

1. doesn't have base-resrtictions that Wolff-Kishner does
2. Aldehye /Ketone + Hg(Zn), HCl -> alkane

Front 11

Wittig Reaction

Back 11

1. method of forming alkenes from aldehydes and ketones.
2. goes by formation of an ylide/ phosphorane

Front 12

Aldol Condensation

Back 12

1. one aldehyde acts as a nucleophile (enol form) and the other as the target (keto form)
2. Higher temps and stronger bases are need to make a,b- unsaturated aldehydes (lose h2O)

Front 13

Michael Rxn

Back 13

1. Nucelophilic Sn2 rxn between two a,b unsaturated carbonyl compounds
2. catalyzed by a base

Front 14

Physical properties of Aldehydes and Ketones

Back 14

1. carbonyl group has a dipole moment, which elecated the bp, but it is NOT as strong as H-bonding

Front 15

Synthesis of Aldehydes and Ketones

Back 15

1. oxidation of alcohols
2. ozonolysis of alkenes
3. friedal-crafts acylation

Front 16

Oxidation of Alcohols

Back 16

1. aldehydes are made from oxidized primary alcohols
2. ketones are made from oxidized secondary alcohols

Front 17

Ozonolysis of Alkenes

Back 17

double bonds can be oxidatively cleaved by ozone to make aldehyes/ ketones

Front 18

Friedal-crafts acylation

Back 18

produces ketones from an acyl halide and an aromatic compound