Transcript Hein and Arena

Introduction to
Organic Chemistry
Chapter 19
Hein and Arena
Version 1.1
Eugene Passer
Chemistry Department
1 College
Bronx Community
© John Wiley and Sons, Inc.
Chapter Outline
19.2 The Carbon Atom
19.3 Hydrocarbons
19.4 Alkanes
19.5 Structural Formulas and
Isomerism
19.6 Naming Alkanes
19.7 Alkenes and Alkynes
19.8 Naming Alkenes and
Alkynes
19.9 Reactions of Alkenes
19.10 Aromatic Hydrocarbons
19.11 Naming Aromatic
Compounds
19.12 Hydrocarbon Derivatives
19.13 Alkyl Halides
19.14 Alcohols
19.15 Naming Alcohols
19.16 Ethers
19.17 Aldehydes and Ketones
19.18 Naming Aldehydes and
Ketones
19.19 Carboxylic Acids
19.20 Esters
19.21 Polymers–Macromolecules
2
Organic Chemistry
The branch of chemistry that deals with
carbon compounds.
– fats, proteins, carbohydrates
– fabrics
– wood and paper products
– plastics
– medicinals
3
Sources of Organic Compounds
Carbon-containing raw materials
– petroleum and natural gas
– coal
– carbohydrates
– fats and oils
4
The
Carbon Atom
5
• The carbon atom is central to all
organic compounds.
Carbon has two stable isotopes
12
6
C and
13
6
Carbon has several radioactive isotopes.
14
6
The C isotope is used in radiocarbon
dating.
6
C.
Carbon has four valence electrons
C
2
1s ,
2
2s ,
2
2p
7
Carbon forms four single covalent
bonds by sharing electrons with other
atoms.
H
HCH
H
8
Carbon forms four single covalent
bonds by sharing electrons with other
atoms.
H
HCH
H
9
The bonds between carbon and other
atoms are often drawn at right angles.
H
HCH
H
10
Actually the angle between the
bonds is 109.5o
11
19.1 c
The bonds point to the corners of
a tetrahedron.
12
19.1 ba
The bonds point to the corners of
a tetrahedron.
14
19.1 a
19.1 d
Space filling models.
15
19.2
A dash represents a
covalent bond.
One covalent bond can
be formed between two
carbon atoms.
C C
single bond
16
One covalent bond can
be formed between two
carbon atoms.
CC
single bond
17
Two covalent bonds
can be formed between
two carbon atoms.
C C
double bond
18
Two covalent bonds
can be formed between
two carbon atoms.
C C
double bond
19
Three covalent bonds
can be formed between
two carbon atoms.
C C
triple bond
20
Three covalent bonds
can be formed between
two carbon atoms.
C C
triple bond
21
Long chains of carbon atoms form by linking
one carbon atom to another through covalent
bonds.
C
C
C
C
C
C
C
seven carbon chain
22
Long chains of carbon atoms form by linking
one carbon atom to another through covalent
bonds.
C
C
C
C
C C
C
C
C
C
nine carbon chain
C
23
Long chains of carbon atoms form by linking
one carbon atom to another through covalent
bonds.
C
C
C
nine carbon
branched chain
C
C
C
C
C
C
24
Hydrocarbons
25
• Hydrocarbons are compounds composed
entirely of carbon and hydrogen atoms
bonded to each other by covalent bonds.
26
• Saturated hydrocarbons have only
single bonds between carbon atoms.
• Unsaturated hydrocarbons contain a
double or triple bond between two
carbon atoms.
• Aromatic hydrocarbons include
benzene and all compounds resembling
benzene.
27
carbon to carbon
single bonds
carbon to carbon carbon to carbon
double bonds
triple bonds
28
19.3
Alkanes
29
• Alkanes are also known as paraffins or
saturated hydrocarbons.
• They are straight- or branched-chain
hydrocarbons.
• There are only single covalent bonds
between the carbon atoms of alkanes.
30
• Successive members in the alkane
series differ from each other by one
carbon and two hydrogen atoms. They
form a homologous series.
• Each member of a homologous series
differs from the next member by a CH2
group.
• The members of a homologous series
are similar in structure but differ in
formula.
31
The general formula of alkanes is CnH2n+2
n=7
2 x 7 + 2 = 16
C7H16
32
Structural Formulas
and Isomerism
33
• The properties of an organic substance
are dependent on its molecular structure.
• Structure means the way in which the
atoms bond within the molecule.
34
• Alkane molecules contain only carboncarbon and carbon-hydrogen bonds.
• Each carbon atom is joined to four other
atoms by covalent bonds.
• These bonds are separated by angles of
109.5o.
• Alkane molecules are essentially nonpolar.
35
The majority of organic compounds are
made from relatively few molecules:
carbon, hydrogen, oxygen, nitrogen and
the halogens.
nitrogen
oxygen
hydrogen
iodine
chlorine
bromine
has
has
has
has
142bond
13bonds
bonds
1bond
bonds
bond
fluorine
carbon
has
ClH
F
Br
IN
O
C
36
Structures of
Common Alkanes
37
CH4
There is 1 possible
structure for CH4.
H
line
space
structure
filling
form of
methane
H C H
H
38
19.4
19.4
CH3CH3
There is 1 possible
structure for C2H6.
H H
space
filling
line
structure
form of
ethane
H C C H
H H
39
19.4
CH3CH2CH3
There is 1 possible structure
for C3H8.
line
space
structure
filling
form of
propane
H H H
H C C C H
H H H
40
19.4
CH3CH2CH2CH3
There are 2 possible structures
for C4H10
line structure
space
filling
form
of
form butane
of butane
H H H H
H C C C C H
H H H H
41
unbranched chain
19.4
CH3
CH2CHCH3
H H
H
H C H
space
filling
line
structure
form of 2-methyl
propane
branched chain
branched chain
H C C C H
H H H
There are 2 possible structures
for C4H10.
42
19.4
normal butane
m.p.
0.5oC
(n-butane)
C
b.p.
–138.3oC
4H10
H H H H
H C C C C H
H H H H
Isomers are compounds with
Normal butane and 2-methyl
the same molecular formula but
propane are isomers.
different structural formulas.
2 –methyl propane
m.p.
C4H10–159.5oC
b.p. – -11.7oC
H H
H
H C H
H C C C H
H H H
43
Pentane (C5H12) has 3 isomers.
Hydrogen
This
is the iscarbon
addedskeleton
to each carbon
with theto
longest
form
four
continuous
bonds. carbon chain. It is
the first isomer of pentane.
H H H H H
H C C C C C H
H H H H H
n-pentane
44
Pentane (C5H12) has 3 isomers.
Hydrogen
Add
the fifth
added
carbon
toatom
each
to
carbon
either
toof
To form
theis next
isomer
write
a four
the
form
middle
four
bonds.
carbon atoms.
carbon
chain.
H
H
H
H C H
C H
H C C C C H
H H H H
2-methylbutane
45
Pentane (C5H12) has 3 isomers.
Hydrogen
addedisomer
to each
carbon
To form
Add
the remaining
theis third
two
carbon
write
aatoms
3 to
form
bonds.
carbon
to
thefour
central
chain.
carbon atom.
H
H
H
H C
H C C C H
H C H
H
H
H
2,2-dimethylpropane
46
Condensed structural
formulas are often
used to save time
and space.
structural
formula
condensed
structural formula
H H
H
H C H
H H H H
H C C C H
H C C C C H
H H H
H H H H
CH3
CH
CH
CH
CH
3
2
2
3
CH CHCH
2
3
In a condensed structural formula the atoms
and groups attached to a carbon atom are
written to the right of that carbon atom.
47
Naming Alkanes
48
• Alkyl groups are used to name organic
compounds.
• The general formula of an alkyl group
is CnH2n+1.
The corresponding
alkane has the formula
CnH2n+2
49
The letter “R” is often used in formulas
to represent any of the possible alkyl
groups.
R= CnH2n+1 (any alkyl group)
R = CH3 —
methyl group
R = CH3CH2 — ethyl group
50
51
The naming of organic compounds is now
done in accordance with the IUPAC
system.
52
IUPAC
RULES
International
Unionthe
of Pure
and continuous
Applied Chemistry
RULE
1. Select
longest
chain of
carbon atoms as the parent compound.
– Consider all alkyl groups attached to it as branch
chains or substituents that have replaced hydrogen
atoms of the parent hydrocarbon. If two chains of
equal length are found, use the chain that has the
larger number of substituents attached to it.
– The alkane’s name consists of the parent
compound’s name prefixed by the names of the
alkyl groups attached to it.
53
This structure has 2 chains.
This chain has 6 carbon atoms.
1
CH3
2
CH2
3
CH
4
CH2
5
CH2
6
CH3
CH3
54
This chain has 4 carbon atoms.
1
CH3
2
CH2
3
CH
CH2
CH2
CH3
CH3
4
55
This is the longest continuous chain.
Select this chain as the parent compound.
1
CH3
2
CH2
3
CH
4
CH2
5
CH2
6
CH3
CH3
56
1
CH3
2
CH2
3
CH
4
CH2
5
CH2
6
CH3
CH3
This is a methyl group.
It is a branch chain and can be considered
to have replaced a hydrogen on the parent
compound.
57
1
CH3
2
CH2
3
CH
4
CH2
5
CH2
6
CH3
CH3
The name of the compound is 33-methylhexane.
58
1
CH3
2
CH2
3
CH
4
CH2
5
CH2
6
CH3
CH3
The name of the compound is 33-methylhexane.
59
IUPAC RULES
RULE 2. Number the carbon atoms in the parent
carbon chain starting from the end closest to the first
carbon atom that has an alkyl group substituted for a
hydrogen atom.
– If the first subsitutent from each end is on the samenumbered carbon, go to the next substituent to determine
which end of the the chain to start numbering.
60
This is the longest continuous chain for this
structure.
Select this chain as the parent compound.
61
If the chain is numbered left to right, the
isopropyl group is on carbon 5.
1 2
3
isopropyl
group
4
5
6
7
8
62
Use
If
theright
chain to
is numbered
left numbering
right toso
left,that
the the
isopropyl group is
is on
oncarbon
the lowest
4. numbered
carbon.
4-isopropyloctane
8 7
6
isopropyl
group
5
4
3
2
1
63
Use
If
theright
chain to
is numbered
left numbering
right toso
leftthat
the the
isopropyl group is
is on
oncarbon
the lowest
2. numbered
carbon.
2-isopropylpentane
5
4
isopropyl
group
3
2
1
64
IUPAC RULES
RULE 3. Name each alkyl group and designate its
position on the parent carbon chain by a number
(e.g., 2-methyl means group attached to C-2).
5
4
3
2
1
2-isopropyl pentane
65
RULE 4. When the same alkyl-group branch chain appears
more than once, indicate this repetition by a prefix (di-, tri-,
tetra- and so forth) written in front of the alkyl group name
(e.g. dimethyl indicates two methyl groups).
–The numbers indicating the alkyl-group positions are separated by a
comma and followed by a hyphen and are placed in front of the
name (e.g., 2,3-dimethyl).
5
4
The methyl group
appears twice
3
2
1
2,3-dimethylpentane
66
IUPAC RULES
RULE 5. When several different alkyl groups are
attached to the parent compound, list them in
alphabetical order (e.g. ethyl before methyl in 3ethyl-4-methyloctane). Prefixes are not included in
alphabetical ordering (ethyl comes before dimethyl).
67
The
group
is
then
onattached
number
This methyl
Since
There
Ethyl
Use
left
isis
there
are
the
alphabetically
totwo
longest
right
are
alkyl
eight
numbering
continuous
groups
carbons
before
socarbon
in
methyl.
chain
that
thisthe
chain,
forethyl
to
this 4.
structure.
the
octane.
Name
group
compound
is
theonethyl
theislowest
group
an octane.
before
numbered
the methyl
carbon.
group.
1
2
3
4
5
6
7
8
methyl
ethyl
3-ethyl-4-methyloctane
68
Alkenes and Alkynes
69
• Alkenes and alkynes • They contain fewer
are unsaturated.
than the maximum
number of hydrogens.
• Alkenes have two • Alkynes have four
fewer hydrogen
fewer hydrogen atoms
atoms than an alkane. than an alkane.
70
Alkenes contain a carbon-carbon double bond.
General formula for alkenes: CnH2n
Alkynes contain a carbon-carbon triple bond.
General formula for alkynes: CnH2n-2
71
72
Alkene
Alkyne
double
bond
73
19.5
Alkene
Alkyne
triple
bond
74
19.5
Naming
Alkenes and Alkynes
75
IUPAC RULES
RULE 1. Select the longest continuous carbon
chain that contains a double or triple bond.
This chain
contains 6
carbon atoms
76
IUPAC RULES
RULE 2. Name this compound as you would
an alkane, but change –ane to –ene for an alkene
and to –yne for an alkyne.
This chain
contains 8
carbon atoms
Nameisthe
This
theparent
longest
continuous octene.
compound
chain.
Select it as the parent
compound.
77
IUPAC RULES
RULE 2. Name this compound as you would
an alkane, but change –ane to –ene for an alkene
and to –yne for an alkyne.
This chain contains a
triple bond. Name the
parent compound
octyne.
78
IUPAC RULES
RULE 3. Number the carbon chain of the
parent compound starting with the end nearer to
the double or triple bond. Use the smaller of the
two numbers on the double- or triple-bonded
carbon to indicate the position of the double or
triple bond. Place this number in front of the
alkene or alkyne name.
79
IUPAC RULES
This end of the chain is closest to the
double bond. Begin numbering here.
80
IUPAC RULES
The name of the parent compound is
1-octene.
4
3
2
1
5
6
7
8
81
IUPAC RULES
The name of the parent compound is
1-octyne.
4
3
2
1
5
6
7
8
82
IUPAC RULES
RULE 4. Branched chains and other groups are
treated as in naming alkanes. Name the
substituent group, and designate its position on
the parent chain with a number.
83
IUPAC RULES
The
is attached to carbon 4.
Thisethyl
is an group
ethyl group.
4
3
2
1
5
6
4-ethyl-1-octene
7
8
84
IUPAC RULES
The ethyl group is attached to carbon 4.
4
3
2
1
5
6
4-ethyl-1-octyne
7
8
85
Reactions of Alkenes
86
• Alkenes are more reactive than their
corresponding alkanes.
• This greater reactivity is due to the
carbon-carbon double bonds.
• Addition at the carbon-carbon double
bond is the most common alkene
reaction.
87
Addition Reactions
Addition adds
Bromine
of bromine
across to
the2-pentene
double bond.
double bond breaks
saturated
2,3-dibromopentane
88
Addition Reactions
Hydrogenof chloride
Addition
hydrogenadds
chloride
across
to 1-butene
the double
bond.
double bond breaks
saturated
2-chlorobutane
89
Aromatic
Hydrocarbons
90
• Benzene and all substances with
structures resembling benzene are
classified as aromatic compounds.
• Aromatic originally referred to the
pleasant odor of these molecules, but
this meaning has been dropped.
91
• Benzene was discovered in 1825 by
Michael Faraday.
• Its molecular formula is C6H6
• The determination of a structural
formula for benzene was difficult.
92
• In 1865 August Kekulé proposed that
the carbon atoms in a benzene molecule
are arranged in a six-membered ring
with one hydrogen atom bonded to each
carbon atom and with three carboncarbon double bonds.
93
benzene Kekulé structure
6 carbons in a ring
3 double bonds
benzene space filling model
94
Benzeneofdoes
not react
like an
alkene.
Instead
addition
reactions
it undergoes
substitution reactions.
Fe
C6H6 + Cl2 → C6H5Cl + HCl
Chlorine substituted for a hydrogen.
95
Benzene is a hybrid of these two Kekulé structures.
96
The structure of benzene can be represented in two
abbreviated ways.
CH
CH
The corner of each hexagon represent a carbon and
97
a hydrogen atom.
Naming Aromatic
Compounds
98
• A substituted benzene is derived by
replacing one or more of benzene’s
hydrogen atoms with atom or group of
atoms.
• A monosubstituted benzene has the formula
C6H5G where G is the group that replaces a
hydrogen atom.
• All hydrogens in benzene are equivalent.
• It does not matter which hydrogen is
replaced by G.
99
Monosubstituted Benzenes
100
• Some monosubstituted benzenes are
named by adding the name of the
substituent group as a prefix to the
word benzene.
• The name is written as one word.
101
nitro group
nitrobenzene
102
ethyl group
ethylbenzene
103
• Certain monosubstituted benzenes have
special names.
• These are parent names for further substituted
compounds.
104
methyl group
toluene
105
hydroxy group
phenol
106
carboxyl group
benzoic acid
107
amino group
aniline
108
• C6H5— is the phenyl group.
• It is used to name compounds that cannot be
easily named as benzene derivatives.
109
diphenylmethane
4-phenyl-2-pentyne
110
Disubstituted Benzenes
111
• Three isomers are possible when two
substituents replace hydrogen in a benzene
molecule.
• The prefixes ortho-, meta- and para- (o-, mand p-) are used to name these disubstituted
benzenes.
112
ortho disubstituted benzene
substituents on adjacent carbons
ortho-dichlorobenzene
(1,2-dichlorobenzene)
mp –17.2oC, bp 180.4oC
113
meta disubstituted benzene
substituents on adjacent carbons
meta-dichlorobenzene
(1,3-dichlorobenzene)
mp –24.82oC, bp 172oC
114
para disubstituted benzene
substituents are on opposite sides of
the benzene ring
para-dichlorobenzene
(1,4-dichlorobenzene)
mp 53.1, bp 174.4oC
115
When one substituent corresponds to a
monosubstituted benzene with a special name,
the monosubstituted compound becomes the
parent name for the disubstituted compound.
nitrophenol
phenol
116
When one substituent corresponds to a
monosubstituted benzene with a special name,
the monosubstituted compound becomes the
parent name for the disubstituted compound.
m-nitrotoluene
toluene
117
Tri- and Polysubstituted
Benzenes
118
• When a benzene ring has three or more
substituents, the carbon atoms in the
ring are numbered.
• Numbering starts at one of the
substituent groups.
• The numbering direction can be
clockwise or counterclockwise.
• Numbering must be in the direction
that gives the substituent groups the
lowest numbers.
119
6-chloro
clockwise
numbering
1-chloro
6
4-chloro
5
1
4
2
3
1,4,6-trichlorobenzene
120
counterclockwise
numbering
2-chloro
chlorine substituents
have lower numbers
1-chloro
2
4-chloro
3
1
4
6
5
1,2,4-trichlorobenzene
121
• When a compound is named as a
derivative of a special parent
compound, the substituent of the parent
compound is considered to be on C-1
of the ring.
122
11
66
22
55
33
44
toluene
2,4,6-trinitrotoluene
(TNT)
123
Hydrocarbon
Derivatives
124
• Hydrocarbon derivatives are compounds
that can be synthesized from a
hydrocarbon.
• In addition to carbon, they contain such
elements as oxygen, nitrogen, or a
halogen.
• The compounds can be grouped into
several classes. The compounds in each
class have similar properties.
125
126
Alkyl
Halides
127
• An alkyl halide has the formula RX
where X = Cl or Br.
• They are formed in a substitution
reaction in which a halogen replaces
hydrogen.
128
uv
RH + X2 → RX + HX
light
When a specific halogen is used the name
reflects this: chlorination
uv
CH3CH3 + Cl2 → CH3CH2Cl + HCl
light
129
Alcohols
130
• Alcohols are organic molecules whose
molecules contain the –OH functional
group.
• The general formula for alcohols is ROH.
131
• Alcohols do not dissociate in water
yielding OH- as do metallic hydroxides.
• The –OH group is attached to the carbon
by a covalent bond and not an ionic bond
as in metallic hydroxides.
• Alcohols form a homologous series.
• Alcohols are classified as primary (1o),
secondary (2o) or tertiary (3o).
132
Primary Alcohol
The carbon to which the – OH
group is attached is bonded to
one carbon.
134
Secondary Alcohol
The carbon to which the –OH
group is attached is bonded to
two carbons.
135
Tertiary Alcohol
The carbon to which the –OH
group is attached is bonded
to three carbons.
136
137
19.6
Polyhydroxy Alcohols
• Alcohols that contain more than one OH
group attached to different carbons are called
polyhydroxy alcohols.
• Monohydroxy: one OH group per molecule.
• Dihydroxy: two OH groups per molecule.
• Trihydroxy: three OH groups per molecule.
138
139
Naming Alcohols
140
IUPAC RULES
1. Select the longest continuous chain of carbon
atoms containing the hydroxyl group.
2. Number the carbon atoms in this chain so
that the one bonded to the –OH group has
the lowest possible number.
141
IUPAC RULES
3. Form the parent alcohol name by replacing
the final –e of the corresponding alkane
name by –ol. When isomers are possible,
locate the position of the –OH by placing
the number (hyphenated) of the carbon atom
to which the –OH is bonded immediately
before the parent alcohol name.
4. Name each alkyl branch chain (or other
group) and designate its position by number.
142
This is the longest continuous chain that
contains an hydroxy group.
Select this chain as the parent compound.
143
This end of the chain is closest to the
OH. Begin numbering here.
144
4
3
2
1
145
4
3
2
1
The corresponding alkane is 3-methylbutane
146
4
3
2
1
3-methyl-2-butanol
147
This is the longest continuous chain that
contains an hydroxy group.
Select this chain as the parent compound.
148
This end of the chain is closest to the
OH. Begin numbering here.
149
5
4
3
2
1
150
5
4
3
2
1
The corresponding alkane is 3-methylpentane
151
5
4
3
2
1
3-methyl-2-pentanol
152
Ethers
153
• An ether has the formula ROR´.
• R and R´ can be the same or different
groups.
• R and R´ can be saturated, unsaturated
or aromatic.
• Saturated ethers have little chemical
reactivity but are often used as
solvents.
154
• Alcohols and ethers are isomeric.
• They have the same molecular formula but
different structural formulas.
• An alcohol and its isomeric ether have
different chemical and physical properties.
155
C2H6O
C2H6O
CH3CH2OH
CH3–O–CH3
ethanol
B.P. 78.3oC
hydrogen bonds
soluble in water
dimethyl ether
B.P. –27.3oC
does not hydrogen bond
insoluble in water
156
Naming Ethers
157
Common Names
Common names of ethers are formed
from the names of the groups attached to
the carbon atom in alphabetical order
followed by the word ether.
CH3CH2CH2 — O — CH2CH3
propyl
ether
ethyl
ethyl propyl ether
158
IUPAC RULES
• RO– is an alkoxy group.
• Ethers are named as alkoxy derivatives
of the longest carbon-carbon chain in
the molecule
159
IUPAC RULES
1. Select the longest carbon-carbon chain and
label it with the name of the corresponding
alkane.
2. Change the –yl ending of the other
hydrocarbon group to –oxy to obtain the
alkoxy group name.
3. Combine the names from steps 1 and 2,
giving the alkoxy name first, to form the
ether name.
160
This is the longest carbon-carbon chain.
Change
Label
it the
withname
the name
of theofother
the corresponding
hydrocarbon
alkane.to –oxy.
group
CH3CH2CH2 — O — CH2CH3
propane
ethoxy
ethyl
3-methyl-2-butanol
161
This is the longest carbon-carbon chain.
Change
Label
it the
withname
the name
of theofother
the corresponding
hydrocarbon
alkane.to –oxy.
group
CH3CH2CH2 — O — CH2CH3
propane
ethoxy
ethyl
ethoxypropane
162
Aldehydes
and Ketones
163
carbon is
carbonyl
double bonded
group
to the oxygen
Aldehydes and ketones contain
the carbonyl group.
164
Aldehydes have at least one hydrogen
bonded to the carbonyl group. The other
group bonded to the carbonyl group is an
alkyl (R) or aromatic (Ar) group.
165
Ketones have two alkyl (R) or aromatic
(Ar) groups bonded to the carbonyl
group.
166
Naming Aldehydes
and Ketones
167
Naming Aldehydes
168
The IUPAC names of aldehydes are
obtained by dropping the –e and adding
-al to the name of the parent hydrocarbon.
butane
butanal
al
169
• The parent hydrocarbon is the longest
chain that carries the –CHO group.
• This chain has 4 carbon atoms.
3
2
1
4
170
• The parent hydrocarbon is the longest
chain that carries the –CHO group.
• This chain has 5 carbon atoms.
5
4
3
2
1
171
• This
The –CHO
is the longest
group is
continuous
always at chain.
the
beginning
of
the
carbon
chain.
The
• Select this chain as the parent compound.
carbonyl carbon is numbered as carbon 1.
5
4
3
2
1
3-methylpentenal
172
• The common names of aldehydes are
derived from the common names of the
carboxylic acids.
• The –ic acid or –oic acid ending of the
acid name is dropped and is replaced
with the suffix –aldehyde.
butyric acid
butyraldehyde
173
Naming Ketones
174
• The IUPAC name of a ketone is
derived from the name of the alkane
corresponding to the longest carbon
chain that contains the ketone-carbonyl
group.
• The parent name is formed by
changing the –e ending of the alkane
to -one.
propane
propanone
one
175
• If the carbon chain is longer than 4
carbons, it’s numbered so that the
carbonyl carbon has the smallest
number possible, and this number is
prefixed to the name of the ketone.
This end of the chain is closest to
C=O. Begin numbering here.
176
• If the carbon chain is longer than 4
carbons, it’s numbered so that the
carbonyl carbon has the smallest
number possible, and this number is
prefixed to the name of the ketone.
1
2
3
4
3-hexanone
5
6
177
• Other groups bonded to the parent
chain are named and numbered
according to the carbon to which they
are attached.
1
2
3
4
5
6
4-methyl-3-hexanone
178
• The common names of ketones are
derived by naming the alkyl or aryl
groups attached to the carbonyl carbon
followed by the word ketone.
ethyl
propyl
ethyl propyl ketone
179
Carboxylic Acids
180
carbonyl group
OH bonded to
a carbonyl
carbon.
Carboxylic acids contain the
carboxyl group.
181
The carboxyl group can also be
written as
or
182
• Open-chain carboxylic acids form a
homologous series.
• The carbonyl group (
) is always
at the beginning of a carbon chain.
• The carbonyl carbon atom is always
designated as C-1.
3
2
1
183
• The IUPAC name of a carboxylic acid
is derived from the name of the alkane
corresponding to the longest carbon
chain that contains the carboxyl group.
• The parent name is formed by
changing the –e ending of the alkane
to –oic acid.
methane
methanone
oic acid
184
• The IUPAC name of a carboxylic acid
is derived from the name of the alkane
corresponding to the longest carbon
chain that contains the caroxyl group.
• The parent name is formed by
changing the –e ending of the alkane
to –oic acid.
propane
propanone
oic acid
185
• Organic acids are usually known by
common names.
• These names usually refer to a natural
source of the acid.
ethanoic
acetic acid
acid
common
IUPAC name
186
• Organic acids are usually known by
common names.
• These names usually refer to a natural
source of the acid.
methanoic
formic acid
acid
common
IUPAC name
187
• This is the simplest aromatic acid.
benzoic acid
188
189
Esters
190
An ester is an organic compound derived
from a carboxylic acid and an alcohol.
carbonyl group
OR´ bonded to
a carbonyl
carbon.
The ester functional group is –COOR.
191
Esterification is the reaction of an acid
and an alcohol to form an ester.
acetic acid
(ethanoic acid)
ethyl alcohol
(ethanol)
ethyl acetate
(ethyl ethanoate)
192
• According to the IUPAC system the
alcohol part of the ester (R΄) is named
first.
ethyl alcohol
193
• According to the IUPAC system the
alcohol part of the ester (R΄) is named
first.
ethyl
194
• According to the IUPAC system the
alcohol part of the ester (R΄) is named
first.
• This is followed by the name of the
acid where the –ic ending of the acid
has been changed to –ate.
ethanoic acid
195
• According to the IUPAC system the
alcohol part of the ester (R΄) is named
first.
• This is followed by the name of the
acid where the –ic ending of the acid
has been changed to –ate.
ethanoate
196
• According to the IUPAC system the
alcohol part of the ester (R΄) is named
first.
• This is followed by the name of the
acid where the –ic ending of the acid
has been changed to –ate.
ethyl ethanoate
197
• The common names of esters are derived
by adding –ate to the name of the acid.
acetic acid
198
• According to the IUPAC system the
alcohol part of the ester (R΄) is named
first.
• This is followed by the name of the
acid where the –ic ending of the acid
has been changed to –ate.
acetate
199
• According to the IUPAC system the
alcohol part of the ester (R΄) is named
first.
• This is followed by the name of the
acid where the –ic ending of the acid
has been changed to –ate.
ethyl acetate
200
201
PolymersMacromolecules
202
• A polymer (macromolecule) is a
natural or synthetic giant molecule
formed from smaller molecules
(monomers).
• Monomers are the small units that
undergo polymerization to form a
polymer.
• Polymerization is the process of
forming very large, high molar-mass
molecules from monomers.
203
Formation of Polyethylene
polyethylene
ethylene monomer
nCH2=CH2 → CH2 CH2[CH2 CH2]n CH2 CH2 CH2 CH3
• n = the number of monomer units.
• n ranges from 2,500 to 25,000
204
205
206