Transcript Ch. 16: Solutions - Quynh Nguyen Official Website

Ch. 14: Carboxylic
Acids, Esters,
Amines and Amides
Chem 20
El Camino College
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Carboxylic Acids, Esters,
Amines
O
O
H
H3C
O
CH3
H3C
carboxylic acid
O
ester
N
H3C
H3C
CH3
amine
O
C
OH
carboxyl group
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Naming Carboxylic Acids
Name the longest carbon chain containing the
carboxyl group.
 Use the suffix “oic acid”
 # the chain to give the carboxyl gp the lowest #
 Give the location and name of other substituents
in alphabetical order, using numbers, hyphens,
and commas between numbers

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4
Name These
H
O
O
O
C
C
C
OH
H3C
OH
methanoic acid
(formic acid)
ethanoic acid
(acetic acid)
H3CH2C
O
OH
OH
propanoic acid
3-methylpentanoic acid
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Benzoic Acid

Benzoic acid is an important carboxylic acid
O
H
C
O
O
C
HC
C
HC
CH
OH
OH
OH
C
H
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Carboxylic Acid Properties
Carboxylic acids are extremely polar
 They have higher boiling pts than alcohols,
ketones, and aldehydes of similar mass

propanal, bp = 49 oC
 1-propanol, bp = 97 oC
 acetic acid, bp = 118 oC


Carboxylic acids with 4 C or less are water
soluble
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Esterification
Carboxylic acids react with alcohols in the
presence of heat and acid (H+) to form esters
and water
 The OH comes off the carboxylic acid, and the
H comes off the alcohol
 A new bond forms to make the ester

O
O
H
H3C
O
+
O
H
CH2CH3
CH2CH3
H3C
O
+
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H2O
Draw the Ester Product
O
O
H
+
OH
H+, heat
O
H
CH3
CH3
H
O
O
O
H+, heat
OH
CH2CH3
O
+
O
H
CH2CH3
O
O
OH
+
H+, heat
O
H
CH3
CH3
O
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Naming Esters
Name the the part that came from an alcohol
(directly connected to an oxygen) first, use “yl”
 Then name the part that came from a carboxylic
acid, use the “oate” suffix

O
O
C
H3C
C
CH3
O
methyl ethanoate
O
H3CH2C
CH3
O
methyl propanoate
C
H3CH2C
CH2CH3
O
ethyl propanoate
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Properties of Esters

The scents of many flowers and fruits are esters
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Types of Amines

Amines are classified as primary (1o), secondary
(2o), or tertiary (3o)
In 1o amines, the N is attached to 1 carbon
 In 2o amines, the N is attached to 2 carbons
 In 3o amines, the N is attached to 3 carbons

:
:
:
:
N
N
N
N
H
H
H3C
H
H
H
ammonia
1o amine
H3C
H3C
2o amine
H H3C
H3C
CH2CH3
3o amine
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Naming of Amines
Name the carbon attachments in alphabetical
order, use the word “amine”
 Use di- and tri- for identical substituents

:
:
:
N
N
N
H 3C
H
H
methylamine
H3C
H3C
H
dimethylamine
H3C
H3C
CH2CH3
ethyldimethylamine
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Properties of Amines
Amines tend to be bad-smelling compounds
 Amines are polar, they have relatively high
boiling points
 Small amines are water soluble.

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Amide
Amides are derivative of carboxylic acids, in
which a nitrogen group replaces the hydroxyl
group. Amide is formed when a salt of carboxylic
with ammonia or amine is heated; a molecule of
water is eliminated.
 Amide can be hydrolyzed back to carboxylic acid
and ammonium salt in acidic solution, or to a salt
of carboxylic acid and ammonia or amine in basic
solution.

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