Download Carboxylic Acids Acid Chlorides

Carboxylic Acids
Nitriles
Natural Products
Nomenclature
Acidity
Preparation
Reactions
Analgesics
CO2H O
OCCH3
(S)(+)ibuprofin
acetyl salicylic acid
HO2C
Fats and Fatty Acids
CO2H
palmitic acid (a fatty acid)
O
CH2
OCR
O
CH
OCR
O
CH2
OCR
a triglyceride
R = n-C 15H31
Prostaglandins
cycloCO2H oxygenase
O
CO2H
HO
arachadonic acid
a prostaglandin
OH
natural mediators of inflammation
Penicillins from mold
Penicillium chrysogenum
O
PhCHCNH
R
S
N
O
CO2H
R = H penicillin G
R= NH 2 ampicillin
From Ergot Fungus
HO2C
CH3
N
H
(+) lysergic acid
NH
Common Nomenclature
Prefix
form
HCO2H
acet
CH3CO2H
propion
butyr
valer
CO2H
CO2H
CO2H
prefix + ic + _acid


Cl
CO2H


-chlorovaleric acid
capro
enanth
capryl
pelargon
capr
CO2H
CO2H
CO2H
CO2H
CO2H
CO2H
Cl Cl
dichloro- -phenylcaprylic acid
I.U.P.A.C. Nomenclature
drop e from alkan e and add "oic acid"
O
OH
heptanoic acid
CO2H
(Z) 2-methyl-2-pentenoic acid
CH2CO2H
CO2H
cyclopentanecarboxylic acid
Br
p-bromophenylethanoic acid
p-bromophenylacetic acid
Dicarboxylic Acids
oxalic acid
HO 2CCO2H or ethanedioic acid
malonic acid
HO 2CCH2CO2H
succinic acid
HO 2CCH2CH2CO2H
glutaric acid
  '
HO 2CCH2CH2CH2CO2H
adipic acid
HO 2CCH2CH2CH2CH2CO2H
pimelic acid
  
HO 2CCH2CH2CH2CH2CH2CO2H
A Diacid
O
OH
HO
Br
Cl
O
-bromo-'-chloroadipic acid
2-bromo-4-chlorohexanedioic acid
Unusually High Melting and
Boiling Points
Boiling Points
o
b.p. C
O
CH3COH
CH3CH2CH2OH
118
97
O
CH3CH2CH
49
CH3CH2OCH3
8
Acidity is due to Delocalization of
the Charge in the Conjugate Base
Alcohol vs. Acid
e
Withdrawing Groups
Enhance Acidity
Benzoic acids
CO2H
CO2H
CO2H
CO2H
CO2H
NO2
CHO
Cl
H
OCH3
3.75
4.0
4.19
4.46
pKa: 3.41
most deactivated
most activated
Deprotonation
O
O
COH
CO Na
+ NaHCO3
pKa 4.2
+ H2CO3
pKa 6.5
Ester Formation
O
O
COH 1) NaOH
COCH2CH2CH2CH3
2) CH3CH2CH2CH2Br
p.t.c.
Carboxylic Acid Preparations
• Oxidation of 1o alcohols and aldehydes with
Na2Cr2O7/H2SO4
• KMnO4 oxidation of alkylbenzenes
• Grignard reaction with CO2 (Carboxylation)
• Hydrolysis of a carboxylic derivative:
e.g. acid chloride, acid anhydride, ester,
amide, nitrile
Grignard Reaction with CO2
Br
1) Mg, ether
2) CO 2, -78 oC
+
3) H 3O
CO2H
Mechanism
Br
CO2H
1) Mg, ether
2) CO2, -78oC
+
3) H3O
Mg

 MgBr
+
H
O
O
C
C
O
O MgBr
Hydrolysis of a Nitrile
Br
KCN
SN2
+
H3O
CN
or 1) NaOH
+
2) H3O
CO2H
Reduction of Carboxylic Acids
Naming Nitriles
CH3
CH3CHCH2CH2CN
4-methylpentanenitrile
CN
cyclohexanecarbonitrile
CN
CN
5-hexynenitrile
Cl
p-chlorobenzonitrile
Dehydration of an Amide
use strong dehydrating agent
or SOCl 2
+ H2O
Reduction of Nitriles
1) LiAlH 4
CN
2) H2O
CH2NH2
Grignard Addition to a Nitrile
CN
O
1) CH3MgBr
+
CH3
2) H3O , heat
heptanenitrile
2-octanone
+ NH3
Partial Mechanism
C N
1) CH3MgBr
O
+
2) H3O , heat
pH = 4-5
CH3
+ NH3
CH3
C
H
N
H3O
+
H3O
CH3
C
an imine
imine hydrolysis
N H
+
The Rest of the Mechanism
CH3
CH3
+
H3O
N H
O
+
H
CH3
CH3
N H
H
H2O
CH3
H
O
H2O
intermolec.
+
H transfer
CH3
NH2
O
H
NH3
O
H
H