Transcript Chapter 25 Alt Notes 0910

Chapter 25
Organic Chemistry I: Compounds
Chapter Goals
Saturated Hydrocarbons
1. Alkanes and Cycloalkanes
2. Naming Saturated Hydrocarbons
Unsaturated Hydrocarbons
3. Alkenes
4. Alkynes
Aromatic Hydrocarbons
5. Benzene
6. Other Aromatic Hydrocarbons
7. Hydrocarbons: A Summary
2
Chapter Goals
Functional Groups
8. Organic Halides
9. Alcohols and Phenols
10.Ethers
11.Aldehydes and Ketones
12.Amines
13.Carboxylic Acids
14.Some Derivatives of Carboxylic Acids
15.Summary of Functional Groups
3
Chapter Goals
Fundamental Classes of
Organic Reactions
16.Substitution Reactions
17.Addition Reactions
18.Elimination Reactions
19.Polymerization Reactions
4
Saturated Hydrocarbons
 Hydrocarbons are chemical
compounds that contain only C and H
atoms.
 Saturated hydrocarbons contain
only single or sigma () bonds.
 There are no double or triple bonds in
these compounds.
 The primary source of hydrocarbons
is petroleum and natural gas.
5
Alkanes and Cycloalkanes
 The simplest saturated hydrocarbons
are called alkanes.
 Methane, CH4, is the simplest alkane.
 The alkanes form a homologous
series.
 Each member of the series differs by
a specific number and kind of atoms.
H
C H
H
H
or CH4
6
Alkanes and Cycloalkanes
 The alkanes differ from each other by a CH2
or methylene group.
 All alkanes have this general formula.
CnH2n+2
 For example ethane, C2H6 , and propane,
C3H8 , are the next two family members.
H
H
H C
H
H
H
H
C
C
H
H
C2H6
H
H
H
H
H
C
C
C
H
H
H
H
H
H C
H
H
C3H8
7
Alkanes and Cycloalkanes
 Isomers are chemical compounds that
have the same molecular formulas but
different structures.
 Two alkanes have the molecular formula C4H10.
 They are a specific type of isomer called
structural isomers.
H H H
H
H
H
H
H
C
C
C
C
H
H
H
H
H
C
C
C
H
H
H
H
H
C
H
H
H C
H
H
n-butane
H
H
H C
H
H
2-methylpropane
8
Alkanes and Cycloalkanes
 Three alkanes have the formula C5H12.
 There are three structural isomers of pentane.
H3C
H2
C
C
H2
H2
C
CH3
n-pentane
9
Alkanes and Cycloalkanes
 Three alkanes have the formula C5H12.
 There are three structural isomers of pentane.
H3C
H2
C
C
H2
H2
C
n-pentane
CH3
CH3
CH3
C
H3C H C
H2
2-methylbutane
10
Alkanes and Cycloalkanes
 Three alkanes have the formula C5H12.
 There are three structural isomers of pentane.
H2
C
H3C
C
H2
H2
C
H
H C
H
H
CH3
CH
CH3
H3C
C
H2
CH3
CH3
H
n-pentane
H C
H
H
C
H3C
CH3
CH3
H
2-methylbutane
H C
H
H
2,2-dimethylpropane
11
Alkanes and Cycloalkanes
 There are five isomeric hexanes, C6H14.
You draw them!
H3C
H2
C
C
H2
H2
C
C
H2
CH3
n-hexane
12
Alkanes and Cycloalkanes
 There are five isomeric hexanes, C6H14.
H3C
H2
C
C
H2
H2
C
CH3
C
H2
n-hexane
CH3
C
H3C H C
H2
H2
C
CH3
2-methylpentane
13
Alkanes and Cycloalkanes
 There are five isomeric hexanes, C6H14.
H3C
H2
C
C
H2
H2
C
CH3
C
H2
n-hexane
CH3
C
H3C H C
H2
H2
C
CH3
2-methylpentane
H2
H2
C H C
CH3
C
H3C
CH3
3-methylpentane
14
Alkanes and Cycloalkanes
 There are five isomeric hexanes, C6H14.
H3C
H2
C
C
H2
H2
C
CH3
C
H2
CH3
n-hexane
C
H3C H C
H2
H2
C
CH3
2-methylpentane
H2
H2
C H C
CH3
C
H3C
CH3
3-methylpentane
CH3
C H2 CH3
C
H3C
CH3
2,2-dimethylbutane
15
Alkanes and Cycloalkanes
 There are five isomeric hexanes, C6H14.
H3C
H2
C
C
H2
H2
C
CH3
C
H2
CH3
C
H3C H C
H2
H2
C
CH3
n-hexane
2-methylpentane
CH3
C H2 CH3
C
H3C
CH3
CH3
C H CH3
H3C H C
2,2-dimethylbutane
2,3-dimethylbutane
H2
H2
C H C
CH3
C
H3C
CH3
3-methylpentane
CH3
16
Alkanes and Cycloalkanes
 The number of structural isomers increases
rapidly with increasing numbers of carbon
atoms.
 The boiling points of the alkanes increase with
molecular weight.
17
Alkanes and Cycloalkanes
 Cyclic saturated hydrocarbons are called
cycloalkanes.
 They have the general formula CnH2n.
 Some examples are:
H2
C
H2C
CH2
C C
H2 H2
cyclopentane
18
Alkanes and Cycloalkanes
 Cyclic saturated hydrocarbons are called
cycloalkanes.
 They have the general formula CnH2n.
 Some examples are:
H2
C
H2C
CH2
C C
H2 H2
cyclopentane
H2C
H2C
H2
C
C
H2
CH2
CH2
cyclohexane
19
Alkanes and Cycloalkanes
 Cyclic saturated hydrocarbons are called
cycloalkanes.
 They have the general formula CnH2n.
 Some examples are:
H 2C
H2C
CH 2
CH 2
H
H C
H
H
H2 H2
C C
H2
C
H2
C
H2C
CH 2
H2C
H2C
CH 2
H2C
H2C
C
H2
H
cyclopentane
H C
H
H
CH 2
CH 2
CH 2
H
cyclohexane
H C
H
H
cyclooctane
20
Naming Saturated Hydrocarbons
 The International Union of Pure and Applied Chemistry (IUPAC)
names for the first 12 "straight-chain" or "normal" alkanes are
given in this table.
Number of carbon
atoms in chain
Name
1
Methane
2
Ethane
3
Propane
4
Butane
5
Pentane
6
Hexane
21
Naming Saturated Hydrocarbons
Number of carbon
atoms in chain
Name
7
Heptane
8
Octane
9
Nonane
10
Decane
11
Unidecane
12
Dodecane
22
Naming Saturated Hydrocarbons
 Other organic compounds are named as
derivatives of the alkanes.
 Branched-chain alkanes are named by the
following rules.
1. Choose the longest continuous chain of carbon
atoms which gives the basic name or stem.
23
Naming Saturated Hydrocarbons
2
3
Number each carbon atom in the basic chain, starting at the
end that gives the lowest number to the first group attached
to the main chain (substituent).
For each substituent on the chain, we indicate the position
in the chain (by an Arabic numeric prefix) and the kind of
substituent (by its name).
 The position of a substituent on the chain is indicated by the lowest
number possible.
 The number precedes the name of the
substituent.
24
Naming Saturated Hydrocarbons
4 When there are two or more substituents of a given kind, use
prefixes to indicate the number of substituents.
 di = 2, tri = 3, tetra = 4, penta = 5, hexa = 6, hepta = 7, octa = 8,
and so on.
5 The combined substituent numbers and names serve as a
prefix for the basic hydrocarbon name.
6 Separate numbers from numbers by commas and numbers
from words by hyphens.
 Words are "run together".
25
Naming Saturated Hydrocarbons
 Alkyl groups (represented by the symbol R) are common
substituents.
 Alkyl groups are fragments of alkanes in which one H
atom has been removed for the connection to the main
chain.
 Alkyl groups have the general formula CnH2n+1.
 In alkyl groups the -ane suffix in the name of the parent
alkane is replaced by -yl.
 A one carbon group is named methyl.
 A two carbon group is named ethyl.
 A three carbon group is named propyl.
26
Unsaturated Hydrocarbons
 The three classes of unsaturated hydrocarbons
are:
1. alkenes and cycloalkenes, CnH2n
2. alkynes and cycloalkynes, CnH2n-2
3. aromatic hydrocarbons
27
Alkenes
 The simplest alkenes contain one C=C bond per
molecule.
 The general formula for simple alkenes is CnH2n.
 The first two alkenes are:
 ethene, C2H4
H
H
C C
H
H C
H
H
H
H
28
Alkenes
 The simplest alkenes contain one C=C bond per
molecule.
 The general formula for simple alkenes is CnH2n.
 The first two alkenes are:
 and propene, C3H6
H
H
H
H C
H
H
C
H
C
H
H
C
H
29
Alkenes
 Each doubly bonded C atom is sp2 hybridized.
 The sp2 hybrid consists of:
 two  bonds (single bonds) and
 one  and one p bond (double bond)
30
Alkenes
 The systematic naming system for alkenes uses the
same stems as alkanes.
 In the IUPAC system, the -ane suffix for alkanes is
changed to -ene.
 Common names for the alkenes have the same stem but use
the suffix -ylene is used.
 In chains of four or more C atoms, a numerical prefix
shows the position of the lowest-numbered doubly
bonded C atom.
 Always choose the longest chain that contains the C=C bond.
31
Alkenes
 Polyenes contain two or more double bonds per
molecule.
 Indicate the number of double bonds with suffixes:
 -adiene for two double bonds.
 -atriene for three double bonds, etc.
 The positions of the substituents are indicated as for
alkanes.
 The position of the C=C bond(s) is/are given the lowest
number(s) possible.
32
Alkenes
H
H
C
C
H
H
C
H
C
H
H
C
H
C
H
H
1,3-hexadiene
33
Alkenes
H
H
C
C
H
H
H C
H
H
H
H
C
C
H
H
C
H
C
H
H
1,3-hexadiene
H
H
H C
H
H
H
H
H
C
C
C
C
C
C
H
H
H
H
1,3,5-hexatriene
34
Alkenes
H
H
C
C
H
H
C
H
C
H
H
C
H
C
H
H
H
C
H
H
H
H
C
C
C
C
H
C
H
H
1,3,5-hexatriene
1,3-hexadiene
H
H H C H H
H
C
H
C
C
C
C
C
H
H H C H
H
2,3-dimethyl-1,3,5-hexatriene
35
Cycloalkenes
 Cycloalkenes have the general formula CnH2n-2.
 Examples are:
 cyclopentene
H
H
H
C
C H
H
C C H
H
H
C
36
Cycloalkenes
 cyclohexene
H
H
H
C
C
H
C H
C
C H
C
H
H
H
H
37
Cycloalkenes
 cycloheptene
H H
H
H
C C
H
C
H
C
H
C
H
C C H
H H H
38
Alkynes
 Alkynes contain CC bonds.
 The simplest alkyne is C2H2, ethyne, or acetylene.
 Alkynes with only one C  C bond have the formula
CnH2n-2.
 Each carbon atom in a C  C bond is sp hybridized.
 Each sp hybrid contains two  bonds and two p bonds.
 The carbon atom will have one single bond and one
triple bond.
39
Alkynes
 Alkynes are named like the alkenes except that
the suffix -yne is used with the characteristic
stem
 The alkyne stem is derived from the name of the
alkane with the same number of carbon atoms.
H
H
H
C
C
H
H
C
C
H
H
H
C
C
C
H
H
H
H
H C
H
H
H
H
H
C
C
H
C
H
H
H
H
H
C
C
C
C
C
H
H
H
H
H
H
H
3-heptyne
H C
H
H
2-octyne
40
Alkynes
 Acetylene is an important industrial chemical.
 It is prepared by the reaction of calcium carbide
with water.
CaC2 s   H 2O   C2 H 2 g   CaOs 
41
Alkynes
 Acetylene burns in a highly exothermic reaction
 The combustion produces temperatures of about 3000°C.
 Acetylene is used in cutting torches for welding.
2C2 H 2 g   5O2 g   4CO2 g   2 H 2Og 
 Alkynes are very reactive
 The two p bonds are sights of special reactivity.
 Addition reactions, such as hydrogenation, are common.
C2 H 2 g   2H 2 g   C2 H 6 g 
42
Hydrocarbons: A Summary
Carbon Atom
Hybridization
sp3
tetrahedral
sp2
trigonal planar
sp linear
C uses
C forms Example
4
bonds
CH4
3
hybrids
& 1p orbital
3
bonds
1 p bond
C2H 4
2 sp hybrids
& 2 p orbitals
2
bonds
2p
bonds
C2H 2
4 sp3 hybrids
sp2
43
Aromatic Hydrocarbons
 Historically, aromatic was used to describe
pleasant smelling substances.
 Now it refers to benzene, C6H6, and derivatives
of benzene.
 Other compounds that have similar chemical
properties to benzene are also called aromatic.
44
Benzene
 The structure of benzene, C6H6, is:
H
H
H
H
H C
H
H
C
C
C
C
C
C
H
H
H
45
Other Aromatic Hydrocarbons
 Coal tar is the common source of benzene and
many other aromatic compounds.
 Some aromatic hydrocarbons that contain fused
rings are:
H
H
 napthalene
H
H
H
H C
H
H
C
C
C
C
H
C
C
C
C
C
C
H
H
H
46
Other Aromatic Hydrocarbons
 phenanthrene
H
H
H
H
C
C
C
C
H
H
C
C
C
C
C
C
C
C
C
C
H
H
H
H
47
Other Aromatic Hydrocarbons
 Many aromatic hydrocarbons contain alkyl
groups attached to benzene rings (as well as to
other aromatic rings).
 The positions of the substituents on benzene
rings are indicated by the prefixes:
 ortho- (o-) for substituents on adjacent C atoms
 meta- (m-) for substituents on C atoms 1 and 3
 para- (p-) for substituents on C atoms 1 and 4
48
Other Aromatic Hydrocarbons
CH 3
CH 3
CH 3
CH 3
CH 3
H
H C
H
H
m-xylene
CH 3
H
H C
H
H
o-xylene
H
H C
H
H
p-xylene
49
Functional Groups
 Functional groups are groups of atoms that
represent potential reaction sites.
 Compounds that contain a given functional
group usually undergo similar reactions.
 Functional groups influence physical properties
as well.
50
Organic Halides
 A halogen atom may replace almost any hydrogen
atom in a hydrocarbon.
 The functional group is the halide (-X) group.
 Examples include:
 chloroform, CHCl3
Cl
Cl
C
H
Cl
51
Organic Halides
 1,2-dichloroethane, ClCH2CH2Cl
H Cl
H C C H
H
H C
H
H
Cl H
52
Organic Halides
 para-dichlorobenzene
Cl
Cl
53
Alcohols and Phenols
 The functional group in alcohols and phenols is
the hydroxyl (-OH) group.
 Alcohols and phenols can be considered
derivatives of hydrocarbons in which one or more
H atoms have been replaced by -OH groups.
 Phenols are derivatives of benzene in which one H
has been replaced by replaced by -OH group.
54
Alcohols and Phenols
 Ethyl alcohol (ethanol), C2H5OH, is the most
familiar alcohol.
H H
H C C OH
H
H C
H
H
H H
55
Alcohols and Phenols
 Phenol, C6H5OH, is the most familiar phenol.
OH
56
Alcohols and Phenols
 Alcohols are considered neutral compounds
because they are only very slightly acidic.
 Alcohols can behave as acids but only in the presence of
very strong bases.
 Phenols are weakly acidic.
 Ka  1.0 x 10-10 for phenol
 Although phenols are very weakly acidic, they
are also very corrosive.
57
Alcohols and Phenols
 Alcohols can be classified into three classes:
1. Primary (1°) alcohols like ethanol have the -OH
group attached to a C atom that has one bond to
another C atom.
H3C
C OH
H2
58
Alcohols and Phenols
2. Secondary(2°) alcohols have the –OH group
attached to a C atom that has bonds to 2 other C
atoms.
 For example,2-propanol:
H3C
HC OH
H3C
59
Alcohols and Phenols
3. Tertiary (3°) alcohols have the –OH group
attached to a C atom that is bonded to 3 other C
atoms.
 For example, 2-methyl-2-propanol
OH
H3C C CH3
CH3
60
Alcohols and Phenols
 The stem for the parent hydrocarbon plus an -ol
suffix is the systematic name for an alcohol.
 A numeric prefix indicates the position of the -OH
group in alcohols with three or more C atoms.
 Common names are the name of the appropriate alkyl
group plus alcohol.
61
Alcohols and Phenols
 Alcohols are named using the stem for the parent
hydrocarbon plus an -ol suffix in the systematic
nomenclature.
 A numeric prefix indicates the position of the -OH group in
alcohols with three or more C atoms.
 Common alcohol names are the name of the appropriate
alkyl group plus the word alcohol.
H2C
H22
C
OH
C
H22
H22
H
C
C
OH
OH
CH33
CH
1-pentanol
1-pentanol
alcohol
1-pentyl alcohol
C
C
H C
H
H33C
C H
C
H
H22
H
H22
C
C
CH
CH33
2-pentanol
2-pentanol
2-pentyl
2-pentyl alcohol
alcohol
H2
H2
C H C
H3C
C
CH3
OH
3-pentanol
62
3-pentyl alcohol
Alcohols and Phenols
 There are several isomeric monohydric acyclic
(contains no rings) alcohols that contain more
than three C atoms.
 There are four isomeric four-carbon alcohols.
63
Alcohols and Phenols
OH
H2
C
HO
H
H C
H
H
H2
C
C
H2
CH
H3C
CH3
CH 3
H
1-butanol
H C
H
H
2-butanol
OH
HO
CH 2
H3C
CH
H3C
CH 2
C
CH 3
CH 3
CH 3
H
H
H C
H
H
2-methyl-1-propanol
H C
H
H
2-methyl-2-propanol
64
Alcohols and Phenols
OH
H2
C
H2
C
H2
C
H2
H2
C H C
CH3
C
H3C
 There are eight isomeric
C five-carbon alcohols.
CH
C
C
CH
HC H C
H
H
OH
You Hdo it!
HO
3
3
3
2
2
2
1-pentanol
2-pentanol
CH3
HO
2-methyl-1-butanol
CH3
C
H3C H C
H2
H2
C
CH3
CH3
CH3
C
C HC
H2
H2
H3C
3-pentanol
C
CH2
OH CH3
2-methyl-2-butanol
C H CH3
H3C H C
OH
3-methyl-2-butanol
CH3H
2
OH
3-methyl-1-butanol
H3C
C
C
CH3 OH
2,2-dimethyl-1-propanol
65
Alcohols and Phenols
 Polyhydric alcohols contain more than one -OH
group per molecule.
OH
OH
C
H2C H CH2
OH
OH
glycerin
HO
OH
OH
C H C H CH2
C H C H C
H2
OH OH
sorbitol
66
Alcohols and Phenols
 Phenols are usually called by their common (trivial)
names.
OH
OH
resorcinol
67
Alcohols and Phenols
 Phenols are usually called by their common (trivial)
names.
OH
OH
CH3
OH
resorcinol
o-cresol
68
Alcohols and Phenols
 Phenols are usually called by their common (trivial)
names.
OH
OH
OH
CH3
CH3
OH
resorcinol
o-cresol
m-cresol
69
Alcohols and Phenols
 Phenols are usually called by their common (trivial)
names.
OH
OH
OH
OH
CH3
CH3
OH
resorcinol
o-cresol
m-cresol
CH3
p-cresol
70
Alcohols and Phenols
 Because the -OH group is quite polar, the properties of
alcohols depend upon the number of -OH groups per
molecule and the size of the organic group.
 The boiling points of monohydric alcohols increase with
increasing molecular weight.
 The solubility of monohydric alcohols in water decrease
with increasing molecular weight.
 Polyhydric alcohols are more soluble in water because of
the two or more polar groups (-OH).
71
Ethers
 Ethers may be thought of as derivatives of water in
which both H atoms have been replaced by alkyl or
aryl groups.
H
O
H
water
72
Ethers
 Ethers may be thought of as derivatives of water in
which both H atoms have been replaced by alkyl or
aryl groups.
H
O
H
water
H3C
O
H
an alcohol
73
Ethers
 Ethers may be thought of as derivatives of water in
which both H atoms have been replaced by alkyl or
aryl groups.
H
O
H
water
H3C
O
H
an alcohol
H3C
O
CH3
an ether
74
Ethers
 Ethers are not very polar and not very reactive.
 They are excellent solvents.
 Common names are used for most ethers.
H3C
O
C
H2
CH3
H3C
O
CH3
H2
C
H3C
O
H2
C
CH3
H
H
H C
H
H
ethylmethyl ether
H C
H
H
dimethyl ether
H
H C
H
H
diethyl ether
75
Aldehydes and Ketones
 The functional group in aldehydes and ketones is
the carbonyl group.
O
R1
R2 or H
carbonyl group
76
Aldehydes and Ketones
 Except for formaldehyde, aldehydes have one H
atom and one organic group bonded to a carbonyl
group.
O
H3C
H
H C
H
H
O
O
H
ethanal
or
acetaldehyde
H
H
H C
H
H
H 3C
H
methanal
or
formaldehyde
H
H C
H
H
C
H2
H
propanal
or
propionaldehyde
77
Aldehydes and Ketones
 Ketones have two organic groups bonded to a
carbonyl group.
O
O
C
C
H3C
H
H C
H
H
O
H2C
CH 3
propanone
or
acetone
C
CH 3
H 2C
CH 3
H
H C
H
H
2-butanone
or
ethylmethylketone
CH 3
H
H C
H
H
CH 2
CH 3
3-pentanone
or
diethylketone
78
Aldehydes and Ketones
 Common names for aldehydes are derived from the
name of the acid with the same number of C atoms.
 IUPAC names are derived from the parent
hydrocarbon name by replacing -e with -al.
H3C
C
H2
H2
C
O
C
H2
C
H
pentanal
or
pentyl aldehyde
79
Aldehydes and Ketones
 Common names for aldehydes are derived from the
name of the acid with the same number of C atoms.
 IUPAC names are derived from the parent
hydrocarbon name by replacing -e with -al.
H3C
C
H2
H2
C
O
O
C
H2
C
pentanal
or
pentyl aldehyde
H3C
H
H3C
C
C
H
CH3
2,3-dimethylproponal
or
2,3-dimethylpropionaldehyde
80
Aldehydes and Ketones
 Common names for aldehydes are derived from the
name of the acid with the same number of C atoms.
 IUPAC names are derived from the parent
hydrocarbon name by replacing -e with -al.
H3C
C
H2
H2
C
O
C
H2
C
pentanal
or
pentyl aldehyde
H3C
H
H3C
C
O
O
C
C
H
H
CH3
2,3-dimethylproponal
or
2,3-dimethylpropionaldehyde
benzanal
or
benzyl aldehyde
81
Aldehydes and Ketones
 The IUPAC name for a ketone is the characteristic stem
for the parent hydrocarbon plus the suffix -one.
 A numeric prefix indicates the position of the carbonyl
group in a chain or on a ring.
H3C
C
H2
H2
C
O
C
H2
C
CH3
2-hexanone
or
methyl pentyl ketone
82
Aldehydes and Ketones
 The IUPAC name for a ketone is the characteristic stem
for the parent hydrocarbon plus the suffix -one.
 A numeric prefix indicates the position of the carbonyl
group in a chain or on a ring.
H3C
C
H2
H2
C
O
C
H2
C
CH3
2-hexanone
or
methyl pentyl ketone
H3C
H2
C
O
C
H2
C
C
H2
CH3
3-hexanone
or
ethyl propyl ketone
83
Aldehydes and Ketones
 The IUPAC name for a ketone is the characteristic stem
for the parent hydrocarbon plus the suffix -one.
 A numeric prefix indicates the position of the carbonyl
group in a chain or on a ring.
O
H3C
C
H2
H2
C
O
C
H2
C
CH3
2-hexanone
or
methyl pentyl ketone
H3C
H2
C
O
C
H2
C
C
H2
C
CH3
CH3
3-hexanone
or
ethyl propyl ketone
acetophenone
or
methyl phenyl ketone
84
Aldehydes and Ketones
 Many aldehydes and ketones occur in nature.
H
HC
C
O
CH3 OH
CH
CH3
O
cinnamaldehyde
testosterone
85
Amines
 Amines are derivatives of ammonia in which one or
more H atoms have been replaced by organic groups
(aliphatic or aromatic or a mixture of both).
 There are three classes of amines.
H
N
H
H
ammonia
86
Amines
 Amines are derivatives of ammonia in which one or
more H atoms have been replaced by organic groups
(aliphatic or aromatic or a mixture of both).
 There are three classes of amines.
H
N
H
H
ammonia
H3C
N
H
H
primary
amine
87
Amines
 Amines are derivatives of ammonia in which one or
more H atoms have been replaced by organic groups
(aliphatic or aromatic or a mixture of both).
 There are three classes of amines.
H
N
H
H
ammonia
H3C
N
H
primary
amine
H
H3C
N
H
CH3
secondary
amine
88
Amines
 Amines are derivatives of ammonia in which one or
more H atoms have been replaced by organic groups
(aliphatic or aromatic or a mixture of both).
 There are three classes of amines.
H
N
H
H
ammonia
H3C
N
H
primary
amine
H
H3C
N
H
CH3
secondary
amine
H3C
N
CH3
CH3
tertiary
amine
89
Amines
 Aniline is the simplest aromatic amine. It is much
less basic than NH3.
 Aniline is a very important industrial chemical.
NH 2
H
H C
H
H
aniline
90
Amines
 Heterocylic amines have one or more N atoms in
a ring structure.
 Many are important in living systems.
N
pyridine
91
Amines
 Heterocylic amines have one or more N atoms in
a ring structure.
 Many are important in living systems.
N
N
pyridine
N
pyrimidine
92
Amines
 Heterocylic amines have one or more N atoms in
a ring structure.
 Many are important in living systems.
N
N
pyridine
N
N
N
pyrimidine
N
N
purine
93
Carboxylic Acids
 Carboxylic acids contain the carboxyl functional
group.
O
C
OH
 The general formula for carboxylic acids is:
 R represents an alkyl or an aryl group
O
C
R1
OH
94
Carboxylic Acids
 IUPAC names for a carboxylic acid are derived
from the name of the parent hydrocarbon.
 The final -e is dropped from the name of the
parent hydrocarbon
 The suffix -oic is added followed by the word
acid.
 Many organic acids are called by their common
(trivial) names which are derived from Greek or
Latin.
95
Carboxylic Acids
O
O
C
C
H
H
H C
H
H
H3C
OH
methanoic acid
or
formic acid
H
H C
H
H
OH
ethanoic acid
or
acetic acid
O
H3C
H
H C
H
H
O
H2
C
C
C
H2
OH
propanoic acid
or
propionic acid
H3C
H
H C
H
H
C
C
H2
OH
butanoic acid
or
butyric acid
96
Carboxylic Acids
 Positions of substituents on carboxylic acid chains
are indicated by numeric prefixes as in other
compounds
 Begin the counting scheme from the carboxyl
group carbon atom.
 They are also often indicated by lower case Greek
letters.
  = 1st C atom
  = 2nd C atom
  = 3rd C atom, etc.
97
Carboxylic Acids
O
H3C H C
C
OH
CH3
2-methylpropanoic acid
or
-methylpropanoic acid
98
Carboxylic Acids
O
H3C H C
C
OH
CH3
CH3
O
C
C
OH
H3C H C
H2
2-methylpropanoic acid 3-methylbutanoic acid
or
or
-methylpropanoic acid -methylbutanoic acid
99
Carboxylic Acids
O
H3C H C
C
OH
CH3
CH3
O
C
C
OH
H3C H C
H2
2-methylpropanoic acid 3-methylbutanoic acid
or
or
-methylpropanoic acid -methylbutanoic acid
O
H2
H3C H C
C
C
C
OH
H2
CH3
4-methylpentanoic acid
or
-methylpentanoic acid
100
Carboxylic Acids
 Dicarboxylic acids contain two carboxyl groups per
molecule.
O
OH
C C
HO
O
oxalic acid
101
Nomenclature of Carboxylic Acids
 Dicarboxylic acids contain two carboxyl groups per
molecule.
O
O
O
OH
C C
HO
O
oxalic acid
HO
C
C
H2
C
OH
malonic acid
102
Nomenclature of Carboxylic Acids
 Dicarboxylic acids contain two carboxyl groups per
molecule.
O
O
O
H2
O
OH
OH
C
C
C
C
C C
C
C
HO
OH
C
HO
H2
HO
O
H2
O
succinic acid
malonic acid
oxalic acid
103
Carboxylic Acids
 Aromatic acids are usually called by their common
names.
 Sometimes, they are named as derivatives of
benzoic acid which is considered to be the "parent"
aromatic acid.
104
Carboxylic Acids
HO
HO
O
O
benzoic acid
Cl
p-chlorobenzoic acid
105
Carboxylic Acids
HO
HO
benzoic acid
HO
O
O
O
Cl
p-chlorobenzoic acid
OH
O
OH
CH3
p-toluic acid
O
phthalic acid
106
Carboxylic Acids
 Acid strengths of simple carboxylic acids vary
little with chain length.
 However, substituents on a carbon atom in the
chain can cause large variations in acid
strengths .
107
Carboxylic Acids
Compound
Name
Ka
formic acid
1.8 x 10-4
acetic acid
1.8 x 10-5
propionic acid
1.4 x 10-5
O
H
C
OH
O
H3C
C
OH
O
H3C
C
H2
C
OH
108
Carboxylic Acids
Compound
O
H3C
C
Name
Ka
acetic acid
1.8 x 10-5
monochloroacetic acid
1.5 x 10-3
dichloroacetic acid
5.0 x 10-2
trichloroacetic acid
2.0 x 10-1
OH
O
Cl
C
H2
C
OH
O
Cl
H C
C
OH
Cl
O
Cl
Cl
C
C
OH
Cl
109
Carboxylic Acids
 The -OH group in the carboxyl group of carboxylic
acids, is displaced in many of their reactions.
 The non -OH portion of a carboxylic acid is called
an acyl group.
R1
O
O
C
C
OH
carboxyl group
R1
acyl group
110
Some Derivatives of
Carboxylic Acids
 Four important classes of compounds contain
acyl groups
 They are all considered to be derivatives of
carboxylic acids.
 In these structures R's may represent either
alkyl or aryl groups.
111
Some Derivatives of
Carboxylic Acids
R1
O
O
O
C
C
C
O
R1
acid anhydride
R1
Cl
acid chloride
112
Some Derivatives of
Carboxylic Acids
R1
O
O
O
C
C
C
O
R1
acid anhydride
R1
acid chloride
O
O
R1
C
Cl
O
ester
R2
R1
C
NH2
amide
113
Some Derivatives of
Carboxylic Acids
 Acid anhydrides are related to their parent acids as
follows:
 The word anhydride means without water.
O
2
H3C
C
O
O
OH
acetic acid
H3C
O
CH3
+
H2O
acetic anhydride
114
Some Derivatives of
Carboxylic Acids
 Acyl halides are much more reactive, and more
volatile, than their parent acids.
 They react with water to form their parent acids and a
hydrohalic acid.
O
H3C
C
O
Cl
acetyl chloride
+
H2O
H3C
OH
+
HCl
acetic acid
115
Some Derivatives of
Carboxylic Acids
 Acyl halides are prepared by reacting their parent acids
with PCl3, PCl5, or SOCl2.
 The more volatile acid halide is then distilled out of the
reaction mixture.
HO
O
Cl
O

+
benzoic acid
PCl5
benzoyl chloride
116
Some Derivatives of
Carboxylic Acids
 Esters are prepared by heating a carboxylic acid with
an alcohol in the presence of a small amount of an
inorganic acid.
 The reaction mixture will contain some ester and water, as
well as unreacted acid and alcohol.
O
H3C
C
OH
ethanoic acid
or
acetic acid
+
H3C
C
H2
OH
ethanol
or
ethyl alcohol
H2SO4
O
H3C
C
O
H2
C
+
H2O
CH3
ethyl ethanoate
or
ethyl acetate
117
Some Derivatives of
Carboxylic Acids
 Esters are usually called by their common names.
 Many simple esters occur naturally and have pleasant
odors.
 Esters are frequently used in fragrances and as artificial
flavors.
H3C
H2
C
O
C
H2
C
O
H2
C
O
CH3
ethyl butanoate
or
ethyl butyrate
odor of pineapples
H3C
O
H2
C
C
H2
H2
C
C
H2
H2
C
C
H2
H2
C
CH3
octyl ethanoate
or
octyl acetate
odor of oranges
118
Some Derivatives of
Carboxylic Acids
 Fats are solid esters of glycerol and (mostly) saturated
acids at room temperature.
 Oils are liquid esters of glycerol and primarily unsaturated
acids at room temperature.
 The "acid" parts of fats and oils usually contain even
numbers of C atoms in naturally occurring fats and oils.
 16 and 18 carbon chains are the most commonly found
chain sizes in nature.
119
Some Derivatives of
Carboxylic Acids
 Some acids that are found (as their esters) in fats
and oils include:
H3C
H2
C
C
H2
H2
C
C
H2
H2
C
C
H2
H2
C
C
H2
H2
C
C
H2
H2
C
C
H2
H2
C
O
C
H2
C
OH
palmitic acid CH3(CH2)14COOH
120
Some Derivatives of
Carboxylic Acids
 Stearic acid is often found in beef fat.
H3C
H2
C
C
H2
H2
C
C
H2
H2
C
C
H2
H2
C
C
H2
H2
C
C
H2
H2
C
C
H2
H2
C
C
H2
H2
C
O
C
H2
C
OH
stearic acid CH3(CH2)16COOH
121
Some Derivatives of
Carboxylic Acids
 Triglycerides are the triesters of glycerol.
 The common name for triglycerides is tri (acid stem)
plus an -in suffix.
 For example, tripalmitin.
(CH2)14CH3
O
OH
C
O
H2C
CH
HO
OH
+
3
CH3(CH2)14COOH
H2C
CH
CH 2
O
glycerin
palmitic acid
O
H
H C
H
H
C
O
CH 2
C
(CH2)14CH3
O
(CH2)14CH3
tripalmitin
122
Some Derivatives of
Carboxylic Acids
 Waxes are esters of long chain fatty acids and
alcohols other than glycerol.
 Commonly, waxes are derived from monohydric
alcohols.
 Beeswax and carnauba wax are esters of myricyl
alcohol, C30H61OH.
123
Some Derivatives of
Carboxylic Acids
 Carnauba wax is often used in car waxes.
O
C25H51
C
O
C30H61
carnauba wax
124
Some Derivatives of
Carboxylic Acids
 Dihydric alcohols (2 –OH’s per molecule) can react
with dicarboxylic acids (2 –COOH’s per molecule) to
form polyesters.
 Ester linkages are formed at both ends of both
molecules to give polymeric esters with very high
molecular weights.
OH
O
C
+
C
O
HO
terephthalic acid
dicarboxylic acid
H2 H2
C C
HO
OH
ethylene glycol
dihydric alcohol
125
Some Derivatives of
Carboxylic Acids
*
n
*
O
O
O
C
CH2
H2C
C
O
O
dacron
126
Some Derivatives of
Carboxylic Acids
 Amides are derivatives of organic acids and primary or
secondary amines.
 The functional groups of amides are:
O
R1
C
O
N
H
H
or
R1
C
O
N
H
R2
or
R1
C
N
R3
127
R2
Some Derivatives of
Carboxylic Acids
 Amides are also named as derivatives of carboxylic
acids.
 The suffix -amide is substituted for -ic acid or -oic
acid.
O
O
H3C
C
N
C
NH2
H
H
ethanamide
or
acetamide
benzamide
128
Some Derivatives of
Carboxylic Acids
 When an aryl or alkyl substituent is present on the N
atom, the letter N and the name of the substituent are
prefixed to the name of the unsubstituted amide.
H2C
O
O
H3C
C
N
C
N
CH3
CH3
CH3
H
N-ethylethanamide
or
N-ethylacetamide
N-ethyl-N-methylbenzamide
129
Some Derivatives of
Carboxylic Acids
 Acetaminophen – “Tylenol” - is an amide.
O
C
HN
CH 3
OH
H
H C
H
H
acetaminophen
130
Summary of the
Functional Groups
 A summary of the functional groups is:
131
132
Substitution Reactions
 In a substitution reaction an atom or group of
atoms attached to a carbon atom is replaced
(substituted for) by another atom or group of
atoms.
 There is no change in the degree of saturation at
the reactive carbon atom.
 Halogenation reactions are an important class of
substitution reactions.
 Chlorine reacts with alkanes in free radical
chain reactions (also substitution reactions).
133
Substitution Reactions
 Free radical chain reactions
 The halogenation of methane is one example.
·· ··
·· Cl ·· Cl ··
·· ··
heat or
uv light
·· .
·
2 · Cl
··
free radicals
134
Substitution Reactions
·· ··
·· Cl ·· Cl ··
·· ··
H
··
H ·· C ·· H
··
H
heat or
uv light
+
··
2 ·· Cl .
··
free radicals
·· .
·· Cl
··
H
··
H ·· C . +
··
H
methyl radical
··
·· Cl ·· H
··
135
Substitution Reactions
heat or
uv light
·· ··
·· Cl ·· Cl ··
·· ··
H
··
H ·· C ·· H
··
H
H
··
H ·· C .
··
H
+
+
··
2 ·· Cl .
··
free radicals
·· .
·· Cl
··
·· ··
·· Cl ·· Cl ··
·· ··
H
··
H ·· C . +
··
H
methyl radical
··
·· Cl ·· H
··
H
·· ··
H ·· C ·· Cl ··
·· ··
H
methyl chloride
+
·· .
·· Cl
··
136
Substitution Reactions
Free radical chain reactions
 Many substitution reactions of alkanes produce more
than one product.
H
H C Cl
H
H
+
Cl
Cl
Cl
C Cl
+
HCl
H
137
Substitution Reactions
H
H C Cl
H
+
Cl
Cl
Cl
H
C Cl
H
+
HCl
H
H
Cl
C Cl
H
+
Cl
Cl
Cl
C Cl
+
HCl
Cl
138
Substitution Reactions
H
H C
H
Cl
+
Cl
Cl
Cl
H
Cl
C
Cl
Cl
+
Cl
Cl
Cl
C
Cl
H
Cl
Cl
HCl
H
H
C
+
H
H
Cl
C
Cl
+
Cl
Cl
Cl
C
Cl
+
HCl
Cl
+
HCl
Cl
139
Substitution Reactions
Nitration reaction of an aromatic hydrocarbon
replaces an H atom attached to an aromatic ring with
a nitro, -NO2, group.
NO
+
HNO
2
H2SO4
2
140
Addition Reactions
An addition reaction involves an increase in
the number of groups attached to carbon.
 The degree of saturation of the molecule is increased.
H
+
C C
H
H H
H
H
Cl
2
H C C H
Cl Cl
141
Addition Reactions
 Hydrogenation is a very important kind of addition reaction.
 Hydrogenation is used to convert unsaturated fats and oils to
saturated fats or oils.
H
+
C C
H
H H
H
H
H
2
H C C H
H H
142
Elimination Reactions
An elimination reaction involves the removal of
groups attached to carbon.
 The degree of unsaturation increases.
Br
Br
HC CH
CH3
H3C
Zn in
H
H
C C
CH3
H
+
C C
acetic acid H C
CH3
H
H3C
3
or ethanol
mixture of cis & trans-2-butene
+
ZnBr
143
2
Elimination Reactions
Dehydration is an important kind of elimination
reaction.
H
OH
H
H
concentrated
HC CH
C C
H
H SO4
H
H
H
2
+
H2O
144
Polymerization Reactions
A polymer is a large molecule that consists of a
high-molecular weight chain of small molecules.
 The small molecules that have been joined to form
the polymer are called monomers.
Synthetic polymers are a relatively new class of
molecules.
 The first one, bakelite, was discovered in 1909.
 Nylon, which is still extensively used, was
discovered in 1930’s.
145
Polymerization Reactions
Addition polymerization is a large commercial
process in the United States.
Polyethylene is the addition polymer made in the
largest quantities in the United States.
 Polyethylene is used to make Coke bottles, plastic bags,
etc.
146
Polymerization Reactions
Addition polymerization
 Polyethylene formation
n H2C CH2
ethylene
catalyst
*
CH2
CH2
n
*
polyethylene
147
Polymerization Reactions
Addition polymerization
 Teflon is the material used in nonstick frying pans and
other kitchen utensils.
F
F
n
C C
F
F
catalyst
heat
tetrafluoroethylene
*
F
F
C
C
n
*
F F
polytetrafluoroethylene
or
Teflon
148
Polymerization Reactions
Formation of rubber
 Natural rubber is a polymer made of isoprene (2-methyl1,3-butadiene) units that form a unique stereoisomeric
structure.
CH3
CH3 H
H3C
H
2
C C
2n
CH2 n *
C
C
C
CH2 CH CH2 CH
*
CH2
H2C
isoprene
natural rubber
149
Polymerization Reactions
Vulcanization of rubber
 Natural rubber is a sticky, soft compound when heated
which limited its commercial potential.
Charles Goodyear discovered in 1839 that heating
rubber with sulfur removed the stickiness and made
the substance elastic.
 This is the basis of modern tire production.
Vulcanization provides disulfide cross-linking bonds
between the isoprene units.
150
Polymerization Reactions
Copolymers
 If two different monomers are mixed and the polymerized,
copolymers are formed.
Styrene butadiene rubber - SBR - is an important
copolymer used in tire production.
151
Polymerization Reactions
Copolymers
H
H
H
3
H
H
C C
C C
H
H
butadiene
C
C
H
+
H
styrene
152
Polymerization Reactions
H
*
H
C
CH2 C
H2C
H
CH2
C
H2
C
C
C
C H2 CH2 H
H
CH2
C
C
n
*
H
H
Styrene - butadiene rubber (SBR)
153
Polymerization Reactions
Condensation Polymers
 Condensation polymers occur when two molecules react
and eliminate a small molecule.
 Molecules eliminated commonly are water and HCl.
Important condensation polymers include nylon,
dacron, and kevlar.
 Dacron is used in clothing to make it wrinkle free.
 Blood does not clot in contact with dacron thus it is used
in artificial arteries.
154
Polymerization Reactions
Condensation Polymers
 Dacron formation
HO
H2 H2
C C
OH
HO
+
O
ethylene glycol
C
O
OH
terephthalic acid
155
Polymerization Reactions
O
O
H O
C C O
H2 H2
C
C
OC C O
H2 H2
n
H
+
H2O
Dacron is a polyester
156
Polymerization Reactions
Condensation Polymers
Nylon was first made by Wallace Carothers in the
1930’s.
 Nylon is widely used in a variety of commercial products
including stockings, rope, guitar strings, fire-proof
clothing.
157
Polymerization Reactions
Condensation Polymers
 Nylon 66 formation
O
HO
C
C
H2
H2
C
C
H2
adipic acid
H2
C
C
O
OH
+
H2N
H2
C
C
H2
H2
C
C
H2
H2
C
C
H2
NH2
hexamethylene diamine
158
Polymerization Reactions
O
H2N
C
C
H2
H2
C
C
H2
H2
C
C
O
H
N
C
H2
H2
C
C
H2
H2
C
C
H2
H2
C
O
N
H
C
n
OH
+
H2O
Nylon is a polyamide
159
Synthesis Question
 TNT, the explosive ingredient in
dynamite, has the correct name of
2,4,6-trinitrotoluene. Draw the
structure of TNT.
160
Synthesis Question
CH3
O N
2
NO
NO
2
2
TNT or 2,4,6-trinitrotoluene
161
Group Question
 Aerobic respiration produces carbon
dioxide and water as its end products.
Anaerobic respiration has different
end products. What are the end
products of anaerobic respiration?
How could you easily detect that
someone has switched from aerobic
to anaerobic respiration?
162
End of Chapter 27
 There are more organic compounds
than any other type of chemical
species.
163