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ALCOHOLPHENOLSETHERS
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OBJECTIVES
Name alcohol compound
Understand the importance of
alcohol Compare and contrast alcohol,
phenol and ether
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Importance
Ethanol is a fuel additive, an
industrial solvent and a
beverage Methanol is a flavoring agent
BHT ( butylated
hydroxytoluene) an
antioxidant food additive
Diethyl ether - anesthetic
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ALCOHOLS
can be classified as primary,
secondary and tertiary
Simple alcohols are namedusing the suffix ol
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ALCOHOLS
Alcohols are compounds in
which an OH group has
replaced one of the hydrogen ofan alkane.
Yet they do not behave like
bases such as sodium
hydroxide and potassiumhydroxide.
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NAMINGALCOHOL
Step 1
Select the longest carbon chain
containing the hydroxyl group,and replace thee ending of
the corresponding alkane with -
ol
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NAMINGALCOHOL
Step 2
Name the carbons of the parent
chain beginning at the endnearer the hydroxyl group
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NAMINGALCOHOL
Step 3
Number all substituents
according to their position onthe chain, and write the name
listing the substituents in
alphabetical order
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Common or Radicofunctional
Nomenclature
The common name of an
alcohol is derived by specifying
the alkyl group to which the
OH group is attached, followed
by the separate word alcohol.
CH OH
Methyl alcohol
CH CH CH
OH
Isopropyl alcohol
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Try this!
OH
CH2
CH2
CH2
CH2
CH2
CH3OH
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Common or Radicofunctional
Nomenclature
Several organic compounds
contains two or more OH
groups.
If compounds contains two
hydroxyl group on adjacent
carbon atoms - glycols
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Common or Radicofunctional
Nomenclature
CH 2 C H C H 2
HH H
CH 2 C H C H
HH 1,2-propanediol (propylene glycol)
1,2, -propanetriol
(glycerol, glycerin)
1,2-ethanediol (ethylene glycol)H CH2
CH2 H
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PHENOL
used to both as the name of
specific substance
( hydroxybenzene) and as thefamily name for all hydroxy-
substituted aromatic
compounds
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Ethers
Simple ethers that contain no
other functional groups are
named by identifying the two
organic groups and adding the
word ether
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Ethers
If more than one ether linkage is
present, or if other functional
groups are present, the ether
part is named as alkoxy
substiuent on the parent
compound
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SubstitutiveNomenclature
The substitutive nomenclature
of alcohols and thiols involves
an important concept of
nomenclature called the
principal group.
The principal group is the
chemical group on which thename is based, and is always
citedas a suffix in the name.
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SubstitutiveNomenclature
For alcohol, theOH is the
principal group and the suffix is
ol while for simple thiols, the
SH is the principal group and its
suffix is thiol.
Note that only certain groups
are cited as principal groups. Ifa compound does not contain a
principal group, it is named as a
substituted hydrocarbon.
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SubstitutiveNomenclature
CH3 CH OH Ethane + ol = ethanol
CH3 CH SHEthane + thiol = ethanethiol
Because the suffix of SH begins with a consonant,
the final e of the alkane is retained
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IUPAC Rules
The parent hydrocarbon isthe longest continuouschain containing thefunctional group.
The parent hydrocarbon isnumbered in the direction
that gives the functional group suffix the lowestpossible number.
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IUPAC Rules
CH31
CH CH3
CH34
OH
CH35
CH4
CH3
CH CH1
CH CH3
OH
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IUPAC Rules
CH3 1
CH2
CH3
CH4
OH
CH5
CH3
CH26
CH27
H
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IUPAC Rules
If there is a functional group
suffix and a substituent, the
functional group suffix gets the
lowest possible number.
Notice that a number is not
needed to designate the
position of a functional groupsuffix in a cyclic compound
because it is assumed to be at
the 1-position.
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IUPAC Rules
OH CH21
CH22
CH23
CH24
CH25
Br
CH 3 1 C H2 C H 23 C H 24
OH
C l
2
1
3
CH 3
O H
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IUPAC Rules
CH3 1
C H2
C H23
CH4
CH 3
C H25 C H 26 C H 37
O H
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IUPAC Rules
If there is more than onesubstituent, the substituents arecited in alphabetical order.
Remember that the name of asubstituent is stated before thename of the parenthydrocarbon, and the functionalgroup suffix is stated afterthename of the parenthydrocarbon.
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IUPAC Rules
CH 3 CH CH CH4
CH3
CH CH 31
B r O H
CH CH3
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IUPAC Rules
1
2
3
4
H CH3
CH3
1
2
3
5
4
H
CH2
CH3
CH3
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General Rules for SubstitutiveNomenclature of Organiccompound
Identify the principal groupWhen a structure has severalcandidates for principal group, thegroup chosen is the one given thehighest priority by the IUPAC:
Carboxylic acid > a nhydride > ester >acid halide > Amide > nitrile > aldehyde> Ketone > alcohol, phenol > thiol >
amine
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General Rules for SubstitutiveNomenclature of Organiccompound
Identify the principal carbonchain.
The principal chain is the carbon chainon which the name is based. Theprincipal chain is identified by applyingthe following criteria in order until adecision can be made:
greatestnumber ofprincipal groups
greatest number of double and triplebonds
greatestlength
greatestnumber ofothersubstituents
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General Rules for SubstitutiveNomenclature of Organiccompound
Number the principal chain
consecutively from one end.
In numbering the principal chain, apply
the f ollowing criteria in order until thereis no ambiguity:
lowest numbers for the principal groups
lowest numbers for multiple bonds, with
double bonds having priority over triplebonds
lowest numbers for other substituents
lowest number for substituent cited first
in the name.
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General Rules for SubstitutiveNomenclature of Organiccompound
Begin construction of the name
with the name of the hydrocarbon
corresponding to the principal
chain. Cite the principal group by its suffix and
number; its number is the last one cited
in the name.
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General Rules for SubstitutiveNomenclature of Organiccompound
Begin construction of the name
with the name of the hydrocarbon
corresponding to the principal
chain. If there is no principal group, name the
compound as a substituted
hydrocarbon.
Cite the names and numbers of theother substituents in alphabetical order
at the beginning of the name.
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Nomenclature ofEthers and Sulfides
Ethers are compounds in which
oxygen is bonded to two alkyl
substituents while sulfides are
compounds in which the sulfur
is bonded to two alkyl
substituents.
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Nomenclature ofEthers and Sulfides
If the alkyl substituent are
identical, the ether/sulfide is a
symmetrical ether/sulfide,
otherwise, it is an
asymmetrical ether/sulfide.
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Nomenclature ofEthers and Sulfides
R O R R S R
Symmetricalether symmetricalsulfide
R O R R S R
Asymmetricalether Asymmetricalsulfide
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Common Nomenclature
The common name of ether isconstructed by citing asseparate words the two groups
attached to the ether oxygen inalphabetical order, followed bythe word ether.
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Common Nomenclature
CH3CH2 O CH2CH3Diethyl ether
CH3 CH2 O CH 3ethyl methyl ether
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Common Nomenclature
CH3 CH
CH3
O CH CH2 CH3
CH3
CH CH2 O C CH3
CH3
CH3
CH3 CH3
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Common Nomenclature
CH CH2
CH3
CH3 CH2 O
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Common Nomenclature
A sulfide is named in a similarmanner, using the word sulfide.( In older literature, the word
thioether was also used
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Common Nomenclature
CH3CH2 S CH3Ethyl methylsulfide
(CH3)2CH S CH(CH3)2diisopropylsulfide
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Substitutive
Nomenclature
CH3O- CH3CH2O - CH3C(CH3)HO-
Methoxy ethoxy isopropoxy
CH3CH2C(CH3)HO - CH3C(CH3)2O
sec-butoxy tertbutoxy
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Substitutive
Nomenclature
C H C HCH 3
O
C H C H C H 3
C H C H 3
CH 3
CH CH3
CH31
CH4
CH CH3
S CH3 -(methylthio) hexane
The parentheses in the name of the sulfide are usedto indicate
that thio is associatedwith methylratherthanwith hexane.
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HeterocyclicNomenclature
A number of important ethers
and sulfides contain an oxygen
or sulfur atom within a ring.
Cyclic compounds with rings
that contain more than one type
of atom are called heterocyclic
compounds.
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HeterocyclicNomenclature
O
CH2CH2
ethylene
oxide
CH2 CH2
ethylene
O
CH2CHPh
styrene oxide
CH CH2Ph
styrene
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HeterocyclicNomenclature
The IUPAC for tetrahydrofuran,
oxolane, is not commonly used
except in indexes such as
Chemical AbstractO
fura
O
ra r furar THF
S
p
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HeterocyclicNomenclature
Oxirane is the parent compound
of a special class of heterocyclic
ethers, called epoxides,that
contain three membered-rings.
A few epoxides are named
traditionally as oxides of the
corresponding alkenes:
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HeterocyclicNomenclature
O
O
1 , 4 - d o x n e
o r s m yd o x n e
O
o x r n e
o r
e h y e n eo x d e
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HeterocyclicNomenclature
However, most epoxides are
named substitutively as
derivatives of oxirane. The
atoms of the epoxide ring are
numbered consecutively with
the oxygen receiving the
number 1 regardless of thesubstituentpresent.
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HeterocyclicNomenclature
O1
CH3
CH22
CH2 CH3
2-ethyl i e
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Properties OfAlcohols,Phenols
And Ethers: Hydrogen Bonding
Alcohols, phenols, and etherscan be thought of as organicderivatives of water in whichone or both of the hydrogenshave been replaced by organicparts: HOH becomes ROH or ROR.
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Properties OfAlcohols,Phenols
And Ethers: Hydrogen Bonding
Thus all three compounds havenearly the same geometry aswater.
Alcohols have higher boilingpoints than alkanes orhaloalkenes of similar molecular
weight.
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Properties OfAlcohols,Phenols
And Ethers:Acidity
Alcohols and phenols, likewater, are both weakly basicand weakly acidic.
As weak acids, alcohols andphenols dissociate to a slightextent in dilute aqueous solution
by donating a proton to water,generating H2O and alkoxideion (RO-) or a phenoxide ion(ArO-).
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Alcohols
Alcohols react with alkali metals
just as water does to yield metal
alkoxides that are themselves
strong bases.
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Methanol
Or methyl alcohol, CH3OH, is
produced commercially from
either carbon monoxide or
carbon dioxide.
It is a colorless liquid, which
boils at 650C
Smells and tastes like ethylalcohol
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Methanol
Is poisonous- breathing the
vapor or drinking the liquid may
cause blindness or death.
Is used in the manufacture of
formaldehyde and other organic
products; as solvent for resins,gums and shellac
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Ethanol
C2H5OH
Called ethyl alcohol, grain
alcohol is the most important
alcohols.
prepared by fermentation of
starch, cellulose, and various
sugars
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Ethanol
Large quantities of ethanol are
synthesized from ethylene and
acetylene
Is a colorless liquid with a
characteristic and somewhat
pleasant odor
It is miscible with water in allproportions
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Ethanol
Boiling point of pure alcohol is
78.370C
It is the least toxic of all the
alcohols and is found in all
alcoholic beverages
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Ethanol
Used as a solvent in tinctures,
essences, and extracts
Preparation of iodoform, ether,
dyes, perfumes, and collodion
Solvent in the lacquer industry
and as motor fuel
Used as additive in some
brands of unleaded gasoline.
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APPLICATION
Ethanol is classified for medical
purposes as a depressant as a
central nervous system (CNS)
depressant.
Increase excitability and
increase in social behavior, but
this results from depression ofinhibition rather than from
stimulation
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APPLICATION
At a blood alcohol concentration
of 0.1% to 0.3%, motor
coordination is affected,
accompanied by loss of balance, slurred speech and
amnesia.
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Application
When blood alcohol
concentration rises to 0.3% to
0.4%,nausea and loss of
consciousness occur.
At concentrations greater than
0.6%, spontaneous respiration
and cardiovascular regulationare affected, ultimately leading
to death.
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Application
The passage of ethanol through
the body begins with its
absorption in the stomach and
small intestines, followed byrapid distribution to all body
fluids and organs.
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Application
In the pituary gland, ethanol
inhibit the production of
hormone that regulates urine
flow, causing increased urineproduction and dehydration.
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Application
In the stomach ethanol, ethanol
stimulates production of acid.
Throughout the body, ethanol
causes blood vessels to dilate,
resulting in flushing of the skin
and a sensation of warmth as
blood moves into capillariesbeneath the surface.
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Application
The result is not warming of the
body, but an increased loss of
heat at the surface.
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Phenols
Aromatic counterparts of alcohol.
The word phenol is used both as
the name of a specific substance
(hydroxyl-benzene) and as the
family name for all hydroxyl-
substituted aromatic compounds.
Phenols are named with phenolused as the parent name rather
than benzene.
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Phenols
Phenols have higher boilingpoints than aromatichydrocarbons.
Phenol itself, for example, boilsat 182oC, whereas toluene boilsat 110.6oC.
Alcohols and phenols haveunusually high boiling pointsbecause, like water, they fromhydrogen bonds in the liquid
state.
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Phenols
Phenols are about a milliontimes more acidic than alcohols.
In fact, some nitro-substituted
phenols approach or surpassthe acidity of carboxylic acids.
One practical consequence ofthis acidity is that phenols aresoluble in dilute aqueousNaOH, but alcohols are not.
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Ethers
Simple ethers that contain no
other functional groups are
named by identifying the two
organic groups and adding theword ether.
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Ethers
If more than one ether linkage is
present, or if other functional
groups are present, the ether
part is named as alkoxysubstituent on the parent
compound.
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Ethers
Ethers, because they lack
hydorxyl groups, cant form
hydrogen bonds and therefore
have lower boiling points.