Transcript Alcohols Phenols and Ethers

ALCOHOLS, PHENOLS and ETHERS
R-OH
Functional group of
an alcohol molecule
C2H5OH
ethanol
ethyl alcohol
propan-2-ol, 2-propanol,
iso, isopro, isoprop,
C3H7OH
rubbing alcohol, or
the abbreviation IPA – isopropyl alcohol)
Chemistry 21A
Dr. Dragan Marinkovic
ALCOHOLS, PHENOLS and ETHERS
Menthol is a major component of mint.
cholesterol
The best source is probably Mentha arvensis,
Corn Mint, whose oil is up to 85% (-)-menthol.
High-density lipoprotein (HDL)
Chemistry 21A
Dr. Dragan Marinkovic
ALCOHOLS, PHENOLS and ETHERS
Glycerin, glycerine, propane-1,2,3-triol
Bombykol
The sex pheromone of the silk moth
A fatty alcohol with two double bonds, bombykol
(tr-10,cis-12-hexadecadien-1-ol), was also shown
to be excreted as a very strong attractive substance
by the female of silk-worm (Bombyx mori).
The bombyx mori
silk moth
Chemistry 21A
Dr. Dragan Marinkovic
ALCOHOLS, PHENOLS and ETHERS
water
water
water
H O H
H O H
H O H
phenol
alcohol
R O H
O H
phenol group
OH
H3C
C
H2
H2
C
OH
propan-1-ol
Chemistry 21A
-OH
ether group
ether
R O R
O
diethyl ether
(ether)
hydroxyl group
R~
alkyl group
O
diphenyl ether
Dr. Dragan Marinkovic
ALCOHOLS, PHENOLS and ETHERS
Nomenclature of Alcohols
1. Alcohols are named by finding the longest continues carbon chain and changing
the ending to –ol (e.g., methanol, ethanol, propanol, etc.).
2. With unsaturated alcohols, two endings are needed, one for the double or triple
bond and one for the hydroxyl group. The –ol suffix is last and takes precedence in
the numbering.
3. If the hydroxyl group is directly attached to an aromatic ring, the compound is
named as a phenol.
4. If the hydroxyl group occurs in a carboxylic acid, aldehyde, or ketone, it is named
as a substituent (hydroxy) because the former functionalities have higher priority.
5. The common names for the alcohols are the alkane chain named as a substituent
followed by the word alcohol (e.g., methyl alcohol, ethyl alcohol, etc.)
H3C
OH
methanol
methyl alcohol
H3C
H2
C
OH
ethanol
ethyl alcohol
Chemistry 21A
H3C
H2
C
OH
C
H2
OH
propan-1-ol, 1-propanol,
C
H3C H CH3
propan-2-ol, 2-propanol,
Dr. Dragan Marinkovic
ALCOHOLS, PHENOLS and ETHERS
C4H9OH alcohols
H2
C
H3C
C
H2
H2
C
CH3
OH
OH
CH3
C
H3C H C
H2
CH3
C
OH
H3C H C
H2
H3C C OH
CH3
1-butanol
2-butanol
2-methyl-1-propanol
2-methyl-2-propanol
n-butyl alcohol
sec-butyl alcohol
isobutyl alcohol
tert-butyl alcohol
OH
HO
HO
H2
C
C
H2
OH
H2
H2
C H C
OH
C
HO
OH
OH
ethanediol
ethylene glycol
OH
HO
trans-3-methylcyclohexanol
H3C
OH
OH
1,2,3-propanetriol
glycerin
Chemistry 21A
1-methylcyclopentanol
Dr. Dragan Marinkovic
ALCOHOLS, PHENOLS and ETHERS
OH
OH
3-methylphenol
phenol
OH
HO
4-ethylphenol
OH
Cl
Cl
alcohol
Cl
2,4,6-trichlorophenol
Chemistry 21A
benzyl alcohol
Dr. Dragan Marinkovic
ALCOHOLS, PHENOLS and ETHERS
H2
C
H3C
C
H2
H2
C
CH3
OH
OH
CH3
C
OH
H3C H C
H2
CH3
C
H3C H C
H2
H3C C OH
CH3
1-butanol
2-butanol
2-methyl-1-propanol
2-methyl-2-propanol
n-butyl alcohol
sec-butyl alcohol
isobutyl alcohol
tert-butyl alcohol
primary alcohol
tertiary alcohol
primary alcohol
HO
HO
H2
C
C
H2
secondary alcohol
OH
OH
H3C
OH
OH
ethanediol
ethylene glycol
trans-3-methylcyclohexanol
Chemistry 21A
1-methylcyclopentanol
Dr. Dragan Marinkovic
ALCOHOLS, PHENOLS and ETHERS
Water has an unusually high boiling point
because of the hydrogen bonds between the H2O molecules.
Alcohols can form similar hydrogen bonds.
As a result, alcohols have boiling points that
are much higher than alkanes with similar molecular weights.
The boiling point of ethanol, for example, is 78.5ºC, whereas propane,
with about the same molecular weight, boils at -42.1ºC.
The difference in boiling
points between alkanes
and alcohols with the
same number of carbon
atoms decreases when
the total number of carbons increases (i.e. with the increase of hydrophobic character of
alcohols).
CH3CH2OCH2CH3
CH3CH2CH2CH2OH
BP = 34.5ºC
BP = 117.2ºC
d = 0.7138 g/mL
d = 0.8098 g/mL
insoluble in
water
soluble in water
Chemistry 21A
Dr. Dragan Marinkovic
ALCOHOLS, PHENOLS and ETHERS
Solubilities of Alcohols in Water
Solubility in
Formula
Name
Water (g/100 g)
CH3OH
CH3CH2OH
CH3(CH2)2OH
OH
OH
methanol
infinitely soluble
ethanol
infinitely soluble
OH
propanol
infinitely soluble
CH3(CH2)3OH
butanol
9
CH3(CH2)4OH
pentanol
2.7
CH3(CH2)5OH
hexanol
0.6
CH3(CH2)6OH
heptanol
0.18
CH3(CH2)7OH
octanol
0.054
CH3(CH2)9OH
decanol
insoluble in water
Chemistry 21A
OH
hydrophilic part of the molecule
OH
hydrophobic part of the molecule
OH
Dr. Dragan Marinkovic
ALCOHOLS, PHENOLS and ETHERS
As the length of the alcohol increases,
the effect of hydrogen bonding
decreases and hydrophobic forces
become dominant.
The difference in boiling points between
alkanes and alcohols with thw same
number of carbon atoms decreases when
the total number of carbons increases
(i.e. with the increase of hydrophobic
character of alcohols).
Chemistry 21A
Dr. Dragan Marinkovic
ALCOHOLS, PHENOLS and ETHERS
dehydration reaction
synthesis of ethers
H3C
H2
C
C
H2
OH
+
HO
Chemistry 21A
C
H2
H2
C
H2SO4
CH3
H3C
H2
C
C
H2
O
C
H2
H2
C
CH3
Dr. Dragan Marinkovic
ALCOHOLS, PHENOLS and ETHERS
Chemistry 21A
Dr. Dragan Marinkovic
ALCOHOLS, PHENOLS and ETHERS
H3C
C
H2
oxydation
oxydation
H
ethanol
acetaldehyde
Chemistry 21A
H3C
O
H3C
OH
O
OH
acetic acid
Dr. Dragan Marinkovic
ALCOHOLS, PHENOLS and ETHERS
H3C H CH3
C
secondary
alcohol
oxydation
CH3
H3C
O
OH
isopropyl alcohol
(2-propanol)
dimethyl ketone
(acetone)
R
R'
OH
R"
tertiary
alcohol
no reaction
oxydation
CH3
H3C
OH
oxydation
no reaction
CH3
Chemistry 21A
Dr. Dragan Marinkovic
ALCOHOLS, PHENOLS and ETHERS
C2H5OH
ethanol
ethyl alcohol
Made from corn and other crops
(fermentation)
yeast
C6H12O6
→
C2H5OH + O2
Pure 100% ethanol has an
octane rating of 113.
Adding 10% ethanol to
gasoline raises the
overall octane by 2 to 3 points.
Lower BTU value than gasoline
2C2H5OH + 2CO2
→
CH3COOH + H2O
H2C
CH2
ethylene
(ethene)
70 atm
300oC
H3C
C
H2
OH
For most of human history, acetic acid,
in the form of vinegar, has been made
by acetic acid bacteria of the genus Acetobacter.
Chemistry 21A
Dr. Dragan Marinkovic
ALCOHOLS, PHENOLS and ETHERS
Chemistry 21A
Dr. Dragan Marinkovic
ALCOHOLS, PHENOLS and ETHERS
heat, pressure, catalyst
CO + 2H2
CH3OH
CH3OH → H2C=O → HCOOH
methanol formaldehyde
formic acid
Aqueous solution of formaldehyde
is called formalin used for storing
specimens and cadavers.
Methanol is produced naturally
in the anaerobic metabolism of
many varieties of bacteria
common laboratory solvent
traditional denaturant for ethanol,
thus giving the term methylated spirit
About 40% of methanol is converted to
formaldehyde, and from there into
products as diverse as plastics, plywood, paints,
explosives, and permanent press textiles.
Drag racers and mud racers
also use methanol as their
primary fuel source.
Chemistry 21A
Dr. Dragan Marinkovic
ALCOHOLS, PHENOLS and ETHERS
propan-2-ol, 2-propanol,
iso, isopro, isoprop,
C3H7OH
rubbing alcohol, or
the abbreviation IPA – isopropyl alcohol)
Ethylene glycol
Monoethylene glycol
MEG
1,2-ethanediol
widely used as an
automotive antifreeze
odorless, colorless, syrupy,
sweet tasting, toxic liquid
propylene glycol, 1,2-propanediol,
1,2-Dihydroxypropane, methyl ethyl glycol (MEG),
methylethylene glycol, PG, Sirlene, Dowfrost
moisturizer in medicines,cosmetics, food,
toothpaste, mouth wash, and tobacco products
Chemistry 21A
Dr. Dragan Marinkovic
ALCOHOLS, PHENOLS and ETHERS
Glycerin, glycerine, propane-1,2,3-triol
In foods and beverages,
glycerol serves as a humectants,
solvent and sweetener, and may
help preserve foods. It is also
used as filler in commercially
prepared low-fat foods (e.g.,
cookies), and as a thickening
agent in liqueurs. Glycerol also
serves as a way, along with water,
to preserve certain types of leaves.
Glycerol is also used as a sugar substitute. In this regard, it has approximately 27 calories per
teaspoon and is 60% as sweet as sucrose. Although it has about the same food energy as table
sugar, it does not raise blood sugar levels, nor does it feed the bacteria that form plaques and
cause dental cavities. As a food additive, glycerol is also known as E number E422.
Example of an unsaturated fat triglyceride.
Chemistry 21A
Dr. Dragan Marinkovic
ALCOHOLS, PHENOLS and ETHERS
CH4 < NH3 < HCCH < ROH < H2O < phenols < H2CO3 < RCOOH < HF
ONa
OH
+ NaOH
SB
SA
water insoluble
+ H2O
WB
WA
water soluble
OH
+ NaHCO3
Chemistry 21A
NR
phenol < H2CO3
Dr. Dragan Marinkovic
ALCOHOLS, PHENOLS and ETHERS
Joseph Lister, 1st Baron Lister, (1827 – 1912) was
an English surgeon who promoted the idea of sterile
surgery while working at the Glasgow Royal Infirmary.
He successfully introduced carbolic acid (phenol) to
sterilize surgical instruments and to clean
wounds, which led to reduced post-operative
infections and made surgery safer for patients.
2-Phenylphenol, or ortho-phenylphenol,
is an ingredient in Lysol, and is
an agricultural fungicide.
Chemistry 21A
2-Benzyl-4-chlorophenol
is an ingredient in Lysol.
Dr. Dragan Marinkovic
ALCOHOLS, PHENOLS and ETHERS
4-Chloro-3,5-dimethylphenol, or chloroxylenol,
is a nonirritating topical antiseptic used in
a number of antibacterial soaps.
2,6-di-tert-butyl-4-methylphenol;
2,6-di-tert-butyl-p-cresol (DBPC);
butylated hydroxytoluene; BHT
Chemistry 21A
Butylated hydroxytoluene (BHT),
also known as butylhydroxytoluene,
is a organic compound that is primarily
used as an antioxidant food additive
(E number E321) as well as in cosmetics,
pharmaceuticals, jet fuels, rubber,
petroleum products, and embalming fluid
Dr. Dragan Marinkovic
ALCOHOLS, PHENOLS and ETHERS
4-Hexylresorcinol is a chemical compound with
anaesthetic, antiseptic and antihelmintic properties.
It can be used topically on small skin infections,
or as an ingredient in throat lozenges.
Anthelmintics or antihelminthics are drugs that expel
parasitic worms (helminths) from the body, by either
stunning or killing them. They may also be called
vermifuges (stunning) or vermicides (killing).
4-hexylbenzene-1,3-diol
Raspberry ketone is a natural phenolic
compound that is the primary aroma compound
of red raspberries. It is used in perfumery, in
cosmetics, and as a food additive to impart a
fruity odor.
Chemistry 21A
Dr. Dragan Marinkovic
ALCOHOLS, PHENOLS and ETHERS
PHENOLS are next-generation anti-oxidant found throughout nature
in some of the healthiest foods.
PHENOLS are the common health-giving link that ties together foods
such as Red Wine, Green Tea, Dark Chocolate, and Super-Berries.
Molecular structure of apigenin,
a polyphenol antioxidant
Chemistry 21A
A polyphenol antioxidant is a type of
antioxidant containing a polyphenolic
substructure. In human health these
compounds, numbering over 4000 distinct
species, are thought to be instrumental in
combating oxidative stress, a process
associated with some neurodegenerative
diseases and some cardiovascular diseases.
Dr. Dragan Marinkovic
ALCOHOLS, PHENOLS and ETHERS
dimethyl ether,
an aerosol spray propellant
ether group
ether
R O R
O
diethyl ether
(ether)
A common low boiling solvent
(b.p. 34.6°C), and
an early anaesthetic.
Polyethylene glycol has a low toxicity and is used in a variety of
products. It is the basis of a number of laxatives (such as
Movicol and polyethylene glycol 3350, or MiraLax or GlycoLax).
Polyethylene glycol (PEG) It is the basis of many skin creams, as cetomacrogol, and
sexual lubricants,
Anisole (methoxybenzene)
O
diphenyl ether
Chemistry 21A
An aryl ether and a major
constituent of the essential
oil of anise seed.
Dr. Dragan Marinkovic
ALCOHOLS, PHENOLS and ETHERS
Physical Properties:
The polar nature of the C-O bond (due to the electronegativity difference
of the atoms ) results in intermolecular dipole-dipole interactions.
An ether cannot form hydrogen bonds with other ether molecules since there
is no H to be donated (no -OH group)
Ethers can be involved in H-bonding with systems able to donate H (e.g. water).
The implications of these effects are:
lower melting and boiling points compared to analogous alcohols
solubility in aqueous media similar to analogous alcohols.
CH3CH2OCH2CH3
CH3CH2CH2CH2OH
BP = 34.5ºC
BP = 117.2ºC
d = 0.7138 g/mL
d = 0.8098 g/mL
insoluble in
water
soluble in water
Chemistry 21A
Dr. Dragan Marinkovic
ALCOHOLS, PHENOLS and ETHERS
Ethers can act as a hydrogen-bond acceptor, as shown in the figure
below. But, they can't act as hydrogen-bond donors. As a result, ethers
are less likely to be soluble in water than the alcohol with the same
molecular weight.
The absence of an -OH group in an ether also has important
consequences for its chemical properties.
Unlike alcohols, ethers are essentially inert to chemical reactions.
They don't react with most oxidizing or reducing agents, and they are
stable to most acids and bases, except at high temperatures.
They are therefore frequently used as solvents for chemical reactions.
However, ethers are generally extremely FLAMMABLE and tend,
If exposed to air for longer periods of time, to form EXPLOSIVE
PEROXIDES.
Chemistry 21A
Dr. Dragan Marinkovic
ALCOHOLS, PHENOLS and ETHERS
A thiol is a compound that contains the functional group
composed of a sulfur atom and a hydrogen atom (-SH).
Being the sulfur analogue of an alcohol group (-OH), this
functional group is referred to either as a thiol group or a sulfhydryl group.
More traditionally, thiols are often referred to as mercaptans.
The preferred method (used by the IUPAC) is to add the suffix -thiol to
the name of the alkane. The method is nearly identical to naming an
alcohol. Example: CH3SH would be methanethiol.
An older method, the word mercaptan replaces alcohol in the name of
the equivalent alcohol compound. Example: CH3SH would be methyl
mercaptan. (CH3OH would be methyl alcohol)
Chemistry 21A
Dr. Dragan Marinkovic
ALCOHOLS, PHENOLS and ETHERS
Many thiols are colorless liquids having an odor resembling that of garlic.
The odor of thiols is often strong and repulsive, particularly for those of
low molecular weight
Natural gas distributors began adding various forms of pungent thiols, originally ethanthiol,
to natural gas, which is naturally odorless, after the deadly 1937 New London School
explosion in New London, Texas. Most gas odorants utilized in the world contain mixtures H3C
of mercaptans and sulfides, with t-butyl mercaptan as the main odor constituent.
Cysteine
Chemistry 21A
(oxydation)
CH3
SH
CH3
Cystine,
showing
disulfide
bond
Dr. Dragan Marinkovic
ALCOHOLS, PHENOLS and ETHERS
Diallyl disulfide (4,5-dithia-1,7-octadiene)
is an organosulfur compound, along with
diallyl trisulfide and diallyl tetrasulfide it is one of the
principal components of the distilled oil of garlic.
Chemistry 21A
Dr. Dragan Marinkovic
ALCOHOLS, PHENOLS and ETHERS
2R-SH + (O) → R-S-S-R + H2O
2CH3SH + (O) → CH3-S-S-CH3
thiol
disulfide
2CH3SH + Pb2+ → CH3-S-Pb-S-CH3 + 2H+
Coenzyme A (CoA, CoASH, or HSCoA) is a
coenzyme, notable for its role in the synthesis
and oxidation of fatty acids, and the oxidation
of pyruvate in the citric acid cycle.
Chemistry 21A
Dr. Dragan Marinkovic
ALCOHOLS, PHENOLS and ETHERS
Chemistry 21A
Dr. Dragan Marinkovic
ALCOHOLS, PHENOLS and ETHERS
Chemistry 21A
Dr. Dragan Marinkovic