Carboxylic Acids And Their Derivatives
1435-1436
2014-2015
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Carboxylic Acids And Their Derivatives
Chapter nine introduces carboxylic acids and their derivatives. The
chemistry is very similar to that of aldehydes and ketones because of the
presence of the carbonyl group . The main topics in this chapter that the
students should know and understand include:
The structure of carboxylic acids
The common and IUPAC nomenclature of carboxylic acids
The physical properties of carboxylic acids
The Factors affecting acidity of carboxylic acids.
The different ways to make carboxylic acids
Salt formation reactions of carboxylic acids
The nucleophilic substitution reactions at the carbonyl carbon and
the specific products formed in each case.
 The chemistry of carboxylic acid derivatives
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Carboxylic Acids And Their Derivatives
Structure Of Carboxylic Acids
 Carboxylic acids are organic acids contain one or more carboxyl
group, which is a combination of carbonyl group C=O and hydroxyl
group O-H
 It is often written in condensed form as –CO2H or –COOH
Carboxylic acids are classified as aliphatic R-COOH or aromatic
Ar-COOH depending on the group bonded to the carboxylic group.
 The simplest acid is formic acid R= H
 The fatty acid is long chain aliphatic acids CH3-(CH2)16-COOH
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Carboxylic Acids And Their Derivatives
Nomenclature Of Carboxylic Acids
Common Nomenclature
Some carboxylic acids are called after characteristic properties or their origin.
All common names ending -ic acid
Formula
HCOOH
CH3COOH
CH3CH2COOH
CH3 (CH2)2COOH
CH3 (CH2)3COOH
Common name
formic acid
acetic acid
propionic acid
butyric acid
valeric acid
origin of name
Latin for ant
Latin for vinegar
Greek for milk
Latin for butter
valerian root
The positions of the carbons present on the acid chain, are located by the
Greek letters α indicating the carbon atom next to COOH group (C2), β (C3),
etc.
5 4 3 2 1
-C—C—C—C—COOH
δ γ β α
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Carboxylic Acids And Their Derivatives
 Example of dicarboxylic acids
HOOC
COOH
Succinic acid
 Some aromatic acids have common names
COOH
COOH
OH
Benzoic acid
Salicylic acid
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Carboxylic Acids And Their Derivatives
IUPAC Nomenclature
Find the longest continuous carbon chain contains the COOH group to get the
root name of the parent hydrocarbon, then replace the ending -e by the suffix –
oic acid.
 Number the chain starting with the carbon of COOH group as C-1
 If there are substituents identify their names, positions and list them as prefixes
in alphabetical order.
Examples:
(CH3)2CH - CH(CH3) - CH2 - CH2 - COOH is called
4,5-Dimethylhexanoic acid
O
C3H7
O
OH
Butanoic acid
C4H9
OH
Pentanoic acid
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Carboxylic Acids And Their Derivatives
Br
NH2 O
O
OH
HOOC
OH
COOH
OH
3-Bromo-2-hydroxy-4-hexenoic acid 3-Aminobutanoic acid
1,4-Butandioic acid
 Cyclic compounds containing one or more COOH groups attached to the ring
are named by identifying the name of the ring followed by the word carboxylic
acid or dicarboxylic acids etc. The carbon atom bearing the carboxylic group is
numbered 1 and the substituents are numbered relative to it.
COOH
COOH
Cyclopropanecarboxylic acid
CH(CH3)2
2-Isopropyl-cyclobutanecarboxylic acid
COOH
Br
Cl
2-Bromo-4-chloro-cyclopentanecarboxylic acid
COOH
NH2
3-Amino-cyclohexanecarboxylic acid 7
Carboxylic Acids And Their Derivatives
 Some aromatic compounds have common names accepted by the
IUPAC also they can be named as benzene carboxylic acids
COOH
COOH
OH
Benzene carboxylic acid
2-Hydroxybenzene carboxylic acid
COOH
COOH
Benzene-1,2-dicarboxylic acid
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Carboxylic Acids And Their Derivatives
Physical Properties OF Carboxylic Acids
1) Boiling Points
 Carboxylic acids have exceptionally high boiling points than alcohols
of identical relative molecular masses, For example:
Propanol
Ethanoic acid
M.F.
M.W
bp / °C
C 3H 8O
60.01
97.2
C 2 H 4 O2
60.05
118
Carboxylic acids have higher boiling points than alcohols and aldehydes,
because their dimeric structures.
Hydrogen-bonded acid dimer
O
R
HO
C
C
OH
O
R
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Carboxylic Acids And Their Derivatives
2)Solubility
Carboxylic acids are polar, they can form hydrogen bonds with water
molecules

 O
H

H
H-Bonds

O
C
R  O H

H
O
H


 The first four aliphatic acids are completely miscible in water. Higher
members are less soluble
 Aromatic acids are insoluble in water
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Carboxylic Acids And Their Derivatives
3) Acid Strength
Carboxylic acids are stronger acids compared to alcohols and phenols
Electron withdrawing substituents near the carboxyl group increase the acidity
 Whereas electron donating substituents decrease the acidity .
 HCOOH > CH3COOH > CH3CH2COOH > CH3CH2CH2CH2COOH ( size of R group)
 Cl3CCOOH > Cl2CHCOOH > ClCH2COOH > CH3COOH ( number of e.w.g.)
COOH
COOH
>
O2 N
NO2
COOH
>
COOH
>
>
COOH
NO2
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Carboxylic Acids And Their Derivatives
Preparation Of Carboxylic acids
1- Oxidation Of Primary Alcohols or aldehydes
R CH2OH
K2Cr2O7/H+
O
R COH
or KMnO4/heat
Primary alcohol
O
R CH
aldehyde
carboxylic acid
O
K2Cr2O7/H+
or KMnO4/heat
R COH
carboxylic acid
2- Oxidation Of Alkyl Benzenes
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Carboxylic Acids And Their Derivatives
3- Carboxylation Of Grignard Reagents
4- Hydrolysis Of Nitriles
or i) KOH
ii) H3O+
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Carboxylic Acids And Their Derivatives
Reactions Of Carboxylic Acids
1- Salts Formation
COOH
COO Na
NaHCO3
+ CO2
+ H2O
Sodium benzoate
OH
NaHCO3
N. R
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Carboxylic Acids And Their Derivatives
2- Nucleophilic Substitution Of Hydroxyl Group
O
O
+
R
L
+
Nu
R
L
Nu
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Carboxylic Acids And Their Derivatives
Carboxylic Acid Derivatives
Acid Chloride
Ester
Amide
Acid anhydride
 The derivatives of carboxylic acids are compounds in which
the -OH of carboxylic acid is replaced by nucleopile (-X for
acid halide, -OR for ester, -NH2, -NHR, -NR2 for amids, OOCR for anhydride).
 Carboxylic acids derivatives can converted to carboxylic
acids by simple acidic or basic hydrolysis.
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Carboxylic Acids And Their Derivatives
1-Nomenclature Of Acid Chlorides
Replace the -ic acid ending in the name of the parent acid by –yl
chloride.
O
H3C
Cl
IUPAC: Ethanoyl chloride
Common : Acetyl chloride
O
O
Cl
Benzoylchloride
CH3CH2
C
Cl
Propanoyl chloride
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Carboxylic Acids And Their Derivatives
2- Nomenclature of esters
 The alkyl group (R’) is written first followed by the name of the parent acid
with replacing of the ending –ic acid by –ate :
(IUPAC) Ethyl ethanoate
(common) Ethyl acetate
Methyl benzoate
O
CH3CH2
C
O
OCH3
HO
O
(IUPAC) Methyl propanoate
145 Chem
Isopropyl-4-hydroxy-5-methyl-5- hexenoate
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Carboxylic Acids And Their Derivatives
3- Nomenclature of amide
 Replace the ending oic acid of the parent acid’s by the word amide
 If there is R group on the nitrogen atom, it is listed first and designated with –N.
O
CH3CH2
(IUPAC) Ethanamide
(common) Acetamide
Benzamide
(IUPAC) N,N-Dimethylmethanamide
(Common) N,N-Dimethylformamide
145 Chem.
C
NHCH3
N-Methylpropanamide
N-Methylpropionamide
N-Ethyl-N-methylbenzamide
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Carboxylic Acids And Their Derivatives
4- Nomenclature of anhydride
 An anhydride is named by replacing the word acid
corresponding acid by the word anhydride.
(IUPAC) Ethanoic anhydride
Benzoic anhydride
(Common) Acetic anhydride
O
in the
Butandioic anhydride
Succinic anhydride
O
OH
heat
O
OH
O
145 Chem
O
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Carboxylic Acids And Their Derivatives
Preparation of acid derivatives from acid chloride
O
CH3OH
OCH3
O
O
CH3NH2
Cl
NH-CH3
O
O
O
O
ONa
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Carboxylic Acids And Their Derivatives
Reaction of Derivatives of carboxylic acid
On hydrolysis (reaction with H2O) all carboxylic acid derivatves convert to
carboxylic acid.
O
R
H3O+
O
O
R
O
H3O+
R
O
O
R
O
R
O
H
H3O+
NH2
or eq NaOH/H3O+
O
R
Cl
H3O+
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145 Chem.
Carboxylic Acids And Their Derivatives
Questions
MgBr
1- Reaction of
with CO2 under heat and pressure gives:
COOH3
A)
COOH
B)
CH2OH
C)
COOH
D)
2- Oxidation of C6H5CH2OH with KMnO4 gives:
COOH
A)
CH2OH
COOH
B)
c)
CH2OH
D)
OH
NO2
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145 Chem.
Carboxylic Acids And Their Derivatives
3- The most acidic compound is?
A) CH3CH2CH2COOH
Cl
B) CH3CH2CH COOH
Cl
C) CH3CHCH2COOH
D) CH3CH2HC2COOH
O
4- The common name of this compound
CH3CH2
C
CH3
N
is?
CH3
A) N,N-Dimethylacetamide
C) N,N-Dimethylpropionamide
B) N,N-Dimethyl propanamide
D) N,N-Dimethylbutanamide
5- Acid halide react with ammonia to give?
A) Amines
B)Amides
145 Chem
C) Phenols
D) Alcohols
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Carboxylic Acids And Their Derivatives
Thank You for your kind attention !
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