Organic Chemistry, 5th ed.
Marc Loudon
Chapter
8
Introduc)on
to
Alkyl
Halides,
Alcohols,
Ethers,
Thiols,
and
Sulfides
Eric J. Kantorowski
California Polytechnic State University
San Luis Obispo, CA
Chapter
8
Overview
•  8.1
Nomenclature
•  8.2
Structures
•  8.3
Effect
of
Molecular
Polarity
and
Hydrogen
Bonding
on
Physical
ProperAes
•  8.4
Solvents
in
Organic
Chemistry
•  8.5
ApplicaAons
of
Solubility
and
SolvaAon
Principles
•  8.6
Acidity
of
Alcohols
and
Thiols
•  8.7
Basicity
of
Alcohols
and
Ethers
•  8.8
Grignard
and
Organolithium
Reagents
•  8.9
Industrial
PreparaAon
and
Use
of
Alkyl
Halides,
Alcohols,
and
Ethers
2
General
Classifica4ons
•  Inspect
the
carbon
bearing
the
halogen
or
hydroxy
group
•  Classify
as
primary,
secondary,
or
terAary
8.1
Nomenclature
3
General
Classifica4ons
•  Carbons
that
contain
two
or
more
hydroxy
groups
on
adjacent
carbons
are
glycols
•  Thiols,
or
mercaptans,
are
the
sulfur
analogs
of
alcohols
•  The
–SH
group
is
called
the
sul=ydryl
or
mercapto
group
8.1
Nomenclature
4
General
Classifica4ons
•  In
an
ether
an
oxygen
is
bonded
to
two
carbon
groups
•  A
thioether,
or
sulfide,
is
the
sulfur
analog
of
an
ether
8.1
Nomenclature
5
IUPAC
Nomenclature
•  Subs4tu4ve
nomenclature:
Most
broadly
applicable
system
•  Common
nomenclature
(aka
radicofunc4onal
nomenclature):
Used
for
simplest
and
most
common
compounds
8.1
Nomenclature
6
Alkyl
Halides
•  The
common
name
uses
the
name
of
the
alkyl
group
followed
by
the
halide
8.1
Nomenclature
7
Alkyl
Halides
•  Other
common
names
to
learn:
8.1
Nomenclature
8
Alkyl
Halides
•  The
subs)tu)ve
name
treats
the
halide
as
a
subsAtuent
8.1
Nomenclature
9
Alcohols
and
Thiols
•  The
common
name
is
derived
by
specifying
the
alkyl
group,
followed
by
“alcohol”
•  A
few
glycols
have
tradiAonal
names
8.1
Nomenclature
10
Alcohols
and
Thiols
•  The
common
name
used
for
a
thiol
is
mercaptan
•  Thiols
readily
combine
with
heavy
metals;
the
name
derives
from
“mercury
capture”
8.1
Nomenclature
11
Alcohols
and
Thiols
•  The
subs)tu)ve
name
is
generated
from
the
principle
group
•  The
principle
group
is
the
chemical
group
on
which
the
name
is
based
and
is
always
the
suffix
in
the
name
•  The
priori)es
of
principle
groups
will
be
given
as
they
are
encountered
in
upcoming
chapters
8.1
Nomenclature
12
Principle
Group
and
Principle
Chain
1.
IdenAfy
the
principle
group
(e.g.,
‐OH
>
‐SH)
2.
IdenAfy
the
principle
chain
which
is
the
chain:
•  With
the
greatest
number
of
principle
groups
•  With
the
greatest
number
of
double
and
triple
bonds
•  Of
greatest
length
•  With
the
greatest
number
of
other
subsAtuents
8.1
Nomenclature
13
Principle
Group
and
Principle
Chain
3.
Number
the
carbons
of
the
principle
chain
giving
the
lowest
numbers:
•  For
the
principle
groups
•  For
mulAple
bonds
(C=C
>
C≡C)
•  For
other
subsAtuents
•  For
the
subsAtuent
cited
first
in
the
name
8.1
Nomenclature
14
Principle
Group
and
Principle
Chain
4.
Begin
construcAon
of
the
name
with
the
name
of
the
hydrocarbon
corresponding
to
the
principle
chain
•  Cite
principle
group
by
suffix
and
number
•  If
there
is
no
principle
group,
name
the
compound
as
a
subsAtuted
hydrocarbon
•  Cite
the
names
and
numbers
of
other
subsAtuents
in
alphabeAcal
order
8.1
Nomenclature
15
Other
Alcohols
•  For
alcohols
with
more
than
one
–OH
group
use
diol,
triol,
etc.
•  Do
not
drop
the
final
e
of
the
alkane
8.1
Nomenclature
16
Ethers
and
Sulfides
•  The
common
name
is
constructed
by
ciAng
the
two
groups
adached
to
O
or
S
8.1
Nomenclature
17
Ethers
and
Sulfides
•  Ethers
and
sulfides
are
never
treated
as
principle
groups
•  The
subs)tu)ve
name
makes
use
of
the
terms
alkoxy
(RO‐)
and
alkylthiol
(RS‐)
8.1
Nomenclature
18
Heterocycles
•  Some
important
ethers
and
sulfides
are
part
of
a
cyclic
structure
•  An
important
subclass
of
heterocyclic
ethers
are
epoxides
8.1
Nomenclature
19
Bond
Angles
and
Lengths
8.2
Structures
20
Boiling
Points
of
Ethers
and
Alkyl
Halides
•  Most
alkyl
halides,
alcohols,
and
ethers
are
polar
molecules
•  They
possess
permanent
dipoles
8.3
Effect
of
Molecular
Polarity
and
Hydrogen
Bonding
on
Physical
Proper)es
21
Boiling
Points
of
Ethers
and
Alkyl
Halides
•  Polarity
leads
to
greater
intermolecular
adracAon
in
the
liquid
state
8.3
Effect
of
Molecular
Polarity
and
Hydrogen
Bonding
on
Physical
Proper)es
22
Boiling
Points
of
Ethers
and
Alkyl
Halides
•  Molecular
size
and
shape
can
dramaAcally
affect
physical
properAes
8.3
Effect
of
Molecular
Polarity
and
Hydrogen
Bonding
on
Physical
Proper)es
23
Boiling
Points
of
Alcohols
•  Alcohols
have
unusually
high
boiling
points
when
compared
to
structurally
similar
compounds
8.3
Effect
of
Molecular
Polarity
and
Hydrogen
Bonding
on
Physical
Proper)es
24
Hydrogen
Bonding
•  An
adracAon
between
the
H
on
one
atom
with
an
unshared
electron
pair
on
another
8.3
Effect
of
Molecular
Polarity
and
Hydrogen
Bonding
on
Physical
Proper)es
25
Hydrogen
Bonding
•  FormaAon
of
a
hydrogen
bond
requires
a
H‐
bond
donor
and
a
H‐bond
acceptor
8.3
Effect
of
Molecular
Polarity
and
Hydrogen
Bonding
on
Physical
Proper)es
26
Hydrogen
Bonding
•  FormaAon
of
a
hydrogen
bond
requires
a
H‐
bond
donor
and
a
H‐bond
acceptor
•  Best
donors:
O,
N,
halogens
•  Best
acceptors:
O,
N,
F
8.3
Effect
of
Molecular
Polarity
and
Hydrogen
Bonding
on
Physical
Proper)es
27
Classifica4on
of
Solvents
•  Pro4c
(H‐bond
donors)
or
apro4c
•  Polar
(high
dielectric
constant)
or
apolar
•  Donor
(Lewis
base)
or
nondonor
8.4
Solvents
in
Organic
Chemistry
28
Solubility
of
Covalent
Compounds
•  Rule
of
thumb:
Like
dissolves
like
8.4
Solvents
in
Organic
Chemistry
29
Solubility
of
Covalent
Compounds
•  A
compound
is
miscible
if
a
soluAon
is
obtained
when
mixed
in
any
proporAon
with
water
8.4
Solvents
in
Organic
Chemistry
30
Solubility
of
Ionic
Compounds
•  Ionic
compounds
in
soluAon
can
exist
as
ion
pairs
or
dissociated
ions
•  In
an
ion
pair,
each
ion
is
closely
associated
with
an
ion
of
opposite
charge
•  Dissociated
ions,
surrounded
by
a
solvent
shell,
move
more
or
less
independently
8.4
Solvents
in
Organic
Chemistry
31
Ions
in
Solu4on
8.4
Solvents
in
Organic
Chemistry
32
Donor
Interac4ons
8.4
Solvents
in
Organic
Chemistry
33
Cell
Membranes
and
Drug
Solubility
•  Solubility
is
crucial
for
drug
acAon
•  Water
solubility
is
important,
but
the
drug
must
also
be
able
to
arrive
at
its
target
site
•  The
drug
must
be
able
to
pass
through
the
cell
membrane
•  Cell
membranes
are
composed
of
phospholipids
8.5
Applica)ons
of
Solubility
and
Solva)on
Principles
34
Lipids
and
Phospholipids
•  A
lipid
is
a
compound
that
shows
significant
solubility
in
apolar
solvents
•  Lipids
are
defined
by
behavior
rather
than
a
precise
structure
•  They
typically
contain
polar
funcAonal
groups,
but
have
significant
hydrocarbon
character
•  Phospholipids
are
lipids
that
contain
the
phosphate
group
8.5
Applica)ons
of
Solubility
and
Solva)on
Principles
35
Lipids
and
Phospholipids
•  Membrane
phospholipids
are
built
on
a
glycerol
“scaffold”
8.5
Applica)ons
of
Solubility
and
Solva)on
Principles
36
Structure
of
Phospholipids
•  Polar
head
group:
A
hydrophilic
group
that
interacts
favorably
with
water
•  Nonpolar
tail:
A
hydrophobic
group
that
is
not
well
solvated
by
water;
oienAmes
referred
to
as
a
“greasy
group”
•  Molecules
that
contain
these
two
discrete
regions
are
called
amphipathic
8.5
Applica)ons
of
Solubility
and
Solva)on
Principles
37
Structure
of
Phospholipids
8.5
Applica)ons
of
Solubility
and
Solva)on
Principles
38
Structure
of
Cell
Membrane
Bilayer
8.5
Applica)ons
of
Solubility
and
Solva)on
Principles
39
Ca4on‐Binding
Molecules
•  Ionophores
are
molecules
that
form
strong
complexes
with
specific
ions
•  Crown
ethers
are
heterocyclic
ethers
with
regularly
spaced
oxygen
atoms
8.5
Applica)ons
of
Solubility
and
Solva)on
Principles
40
[18]‐Crown‐6
and
Potassium
Ion
8.5
Applica)ons
of
Solubility
and
Solva)on
Principles
41
Ca4on‐Binding
Molecules
•  Cryptands
are
nitrogen‐containing
analogs
of
the
crown
ethers
8.5
Applica)ons
of
Solubility
and
Solva)on
Principles
42
Acidity
of
Alcohols
and
Thiols
•  Alcohols
and
thiols
are
weak
acids
•  pKa
(ROH)
≈
16;
pKa
(RSH)
≈
10
•  The
conjugate
bases
of
alcohols
are
alkoxides
•  The
conjugate
bases
of
thiols
are
mercap4des
8.6
Acidity
of
Alcohols
and
Thiols
43
Forma4on
of
Alkoxides
•  An
alcohol
cannot
be
fully
converted
into
an
alkoxide
with
aqueous
hydroxide
•  Sodium
hydride
or
sodium
metal
must
be
used
8.6
Acidity
of
Alcohols
and
Thiols
44
Forma4on
of
Mercap4des
•  Thiols
are
much
more
acidic
and
can
be
deprotonated
with
hydroxide
or
alkoxide
8.6
Acidity
of
Alcohols
and
Thiols
45
Polar
Effects
on
Alcohol
Acidity
•  SubsAtuted
alcohols
and
thiols
show
the
same
type
of
polar
effect
on
acidity
seen
for
carboxylic
acids
8.6
Acidity
of
Alcohols
and
Thiols
46
Role
of
Solvent
in
Alcohol
Acidity
•  Alkoxide
basicity:
TerAary
>
secondary
>
primary
•  This
trend
is
reversed
in
the
gas
phase
8.6
Acidity
of
Alcohols
and
Thiols
47
Acidity
of
Alcohols
•  Alcohols
and
ethers
have
the
similar
basicity
•  Thiols
are
much
less
basic
8.7
Basicity
of
Alcohols
and
Ethers
48
Organometallic
Compounds
•  Compounds
that
contain
carbon‐metal
bonds
•  Organomagnesium
and
organolithium
are
two
of
the
most
useful
types
•  Grignard
reagents
(R‐Mg‐X):
•  Organolithium
reagents
(R‐Li):
8.8
Grignard
and
Organolithium
Reagents
49
Forma4on
of
Organometallic
•  Grignard:
•  Organolithium:
8.8
Grignard
and
Organolithium
Reagents
50
Charge
Distribu4on
for
C‐M
•  Carbon
is
more
electronegaAve
than
Mg
or
Li
•  This
places
nega)ve
charge
at
the
carbon
8.8
Grignard
and
Organolithium
Reagents
51
Protonolysis
of
Organometallic
Compounds
•  Therefore,
carbon
may
be
conceptually
viewed
as
a
carbanion
8.8
Grignard
and
Organolithium
Reagents
52
Free‐Radical
Halogena4on
of
Alkanes
•  SubsAtuAon
of
a
hydrogen
by
a
halogen
8.9
Industrial
Prepara)on
and
Use
of
Alkyl
Halides,
Alcohols,
and
Ethers
53
Uses
of
Halogen‐Containing
Compounds
•  Alkyl
halides
and
other
halogen‐containing
compounds
have
important
uses
•  Solvents:
CH2Cl2,
CH3Cl
•  Monomers
for
PVC,
Teflon,
Kel‐F
•  Herbicides
and
pesAcides:
8.9
Industrial
Prepara)on
and
Use
of
Alkyl
Halides,
Alcohols,
and
Ethers
54
Produc4on
and
Use
of
Alcohols
and
Ethers
8.9
Industrial
Prepara)on
and
Use
of
Alkyl
Halides,
Alcohols,
and
Ethers
55
Produc4on
and
Use
of
Alcohols
and
Ethers
8.9
Industrial
Prepara)on
and
Use
of
Alkyl
Halides,
Alcohols,
and
Ethers
56
Safety
Hazards
of
Ethers
•  Ethers
undergo
autoxidaAon
in
the
presence
of
oxygen
from
air
•  The
resultant
peroxides
and
hydroperoxides
are
explosive
8.9
Industrial
Prepara)on
and
Use
of
Alkyl
Halides,
Alcohols,
and
Ethers
57