Download W19 Aldehydes ketones I

Organic chemistry II
Zdeněk Friedl
Chapter 19
Aldehydes and ketones I
Solomons & Fryhle: Organic
Chemistry 8th Ed., Wiley 2004
Nucleophilic addition to carbonyl C=O group
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structure of C=O carbonyl group
physical properties of aldehydes and ketones
reaction scheme of aldehydes and ketones
nucleophilic addition AN to C=O group:
cyanohydrins, hemiacetals, acetals, thioacetals
nucleophilic addition-elimination AN(E) to C=O group:
imines, oximes, hydrazones, enamines
nucleophilic addition of phosphorus ylides
oxidation of aldehydes and ketones
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Aldehydes and ketones
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Physical properties of aldehydes and ketones I
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Physical properties of aldehydes and ketones II
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The structure of C=O carbonyl group
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Electron structure of carbonyl C=O group
an electrostatic potential map of acetaldehyde and acetone
Acetone
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The nomenclature of addition, addition-elimination
and addition-substitution reactions of C=O compounds
AN
AN(E)
AN(S)
O
OH
R C
+
H
NuH
R CH
Nu
O
R C
H
+ NuH2
O
+ NuH
R C
O R1
R CH Nu + H2O
O
+ R1-OH
R C
Nu
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AN, AN(E)
The reaction scheme of aldehydes a ketones
H+
δ−
δ+
H
O C
δ−
δ+
O C
H
H
δ−
δ+
O C
α
CH R
H
B
R1
α
CH R
H
B
δ−
Nu
(AN)
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AN
The nucleophilic addition to C=O bond I
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AN
The nucleophilic addition to C=O bond II
an addition of STRONG nucleophile
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AN
The nucleophilic addition to C=O bond III
the reaction is not stereoselective
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AN
Addition of hydrogen cyanide: CYANOHYDRINS
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Amygdalin
[(6-O-β-D-Glucopyranosyl-β-D-glucopyranosyl)oxy]-2-phenylacetonitrile
HO
O
O
O
O
CN
Cyanogenic glycoside which occurs in bitter almonds and seeds of apricots and peaches
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AN
The nucleophilic addition to C=O bond IV
ACID-catalyzed nucleophilic addition
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AN
Addition of alcohols: HEMIACETALS
ACID-catalyzed nucleophilic addition
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AN
Addition of alcohols :
ACETALS
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AN
Addition of thiols: THIOACETALS
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AN(E)
Addition of derivatives of ammonia
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AN(E)
Addition of 1° and 2° amines: IMINES and ENAMINES
ACID-catalyzed addition followed by elimination of water
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AN(E)
Addition of 1° amines: IMINES
ACID-catalyzed addition followed by elimination of water
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AN(E)
Addition of hydroxylamine: OXIMES I
ACID-catalyzed addition followed by elimination of water
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AN(E)
Addition of hydroxylamine: OXIMES II
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AN(E)
HYDRAZONES
WOLFF-KISHNER reduction
NH2-NH2 +
C=O
NH2-N=C
KOH / DEG
180 °C
CH2 + N2
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AN(E)
ENAMINES I
mostly used 2° amines
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AN(E)
Addition of 2° amines: ENAMINES II
the first step: ADDITION
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AN(E)
Addition of 2° amines: ENAMINES III
the second step: acid-catalyzed ELIMINATION
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AE(E)
ENAMINES IV
enamines as nucleophilic substrates
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AE(E)
ENAMINES V
enamines as nucleophilic substrates : ACYLATION
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AE(E)
ENAMINES VI
enamines as nucleophilic substrates : ALKYLATION
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AE(E)
ENAMINES VII
enamines as nucleophilic substrates : ALKYLATION
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AN
Addition of phosphorus YLIDES I
the WITTIG reaction
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AN
Addition of phosphorus YLIDES II
preparation of phosphorus ylides: (R-X = CH3, 1° and 2° alkyl halides)
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AN
Addition of phosphorus YLIDES III
a mechanism of WITTIG reaction
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Oxidation of aldehydes and ketones I
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Oxidation of aldehydes and ketones II
the BAYER-VILLIGER oxidation (H>Ph>3°>2°>1°>CH3)
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AN , AN(E)
Reactions of carbonyl compounds I
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AN
Reactions of carbonyl compounds II
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AN
Reactions of carbonyl compounds III
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Reactions of carbonyl compounds IV
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