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Alcohols, Phenols and EthersFunc�onal Group- OHSuffix to be used - olHomologous series- Methanol (CH3OH) Ethanol (C2H5OH) Propanol (C3H7OH) Butanol (C4H9OH) Pentanol (C5H11OH) and so on
Markownikoff addi�on1. Boiling Point- * Higher than other organic compounds having equal molecular masses* The boiling point decreases with an increase in branching in alipha�c carbon chains
The rela�ve ease of dehydra�on of alcohols follows the following order: Ter�ary > Secondary > Primary
* Methanol is a colourless liquid and boils at 337 K* It is highly poisonous in nature
* Ethanol is a colourless liquid with boiling point 351 K* It is used as a solvent in paint industry and in the prepara�on of a number of carbon compounds
2. Solubility- * The hydroxyl group in alcohol is involved in the forma�on of intermolecular hydrogen bonding* The solubility of alcohol in water decreases with the increase in the size of the alkyl group
Preparatory Methods Physical Proper�es
R-OH
Chemical Proper�es
Reac�ons involving cleavage of O-H bond
Some Commercially Important Alcohols
Methanol
Ethanol
Reac�on with Metals
Reac�on with phosphorus trihalides
Dehydra�on
Acidity of Alcohols
Acidity of Alcohols
Esterifica�on
Oxida�on
Dehydrogena�on
Reac�on with hydrogen halides
Alcohols: Weaker acids than water
Esterifica�on
Reac�ons involving cleavage of C–O bond
R-CH=CH2 H2O/H⁺H2O2
B2H6H2O2/H2O
N2/H2Na + C2H5OHH2/PdLiAlH4i) LiAlH4ii) H2O
i) RMgXii) H2O/H⁺
An� markownikoff addi�onR-CH=CH2
R-C-Cl
RCHO
R-COOHR-COO-R’
For the prepara�on of - 10 alcohol – HCHO 20 alcohol – RCHO 30 alcohol –
Structure
Methanol
Cyclohexanol 2-MethylcyclopentanolDihydric alcohols
Monohydric alcoholsC2H5OH
Part - 1
CH2OHCH2OH
Compounds containing Csp3 -OH bond
Compounds containing Csp2 -OH bond
NomenclatureClassifica�on
* Primary, secondary and ter�ary alcohols* Allylic alcohols* Benzylic alcohols
* Vinylic alcohol
Trihydric alcohols
CH2OHCHOHCH2OH
Alcohol
O
R-C-RO
Prepara�on
Proper�es
Prepara�on
Proper�es
H
H
142 pm 96 pm
108.90C
:O:
HH
OHOH
CH3
CH3 - CH2 - CH2 - O:
:
HH
H H
HO
O
O
H H
2R-O-H + 2Na 2R-O-Na+H2Sodiumalkoxide
6 CH3-C-OH + 2Al 2 CH3-C-O Al+3H2Aluminiumtert-butoxide
tert-Butyl alcohol
CH3
CH3
CH3
CH3( )3
SecondaryPrimary Ter�ary
R CH2OH > CHOH >> R C- OHR
RR
R
R-O: + H-O:-H R-O-H + :OH
::
::
::
Acid Conjugateacid
Conjugatebase
Base
R-C-OH + H-O-R R-C-O-R’ + H-O-HAcid Alcohol Ester
O OH⁺⥮
ROH + HX → R-X + H2O
RCH2OH RCHOCu573K
R-CH-R’ R-C-R’Cu573K
OH O
R-C-OH CH3-C=CH2Cu573K
CH3
CH3 CH3
RCH2OH R-C=O R-C=OOxida�on
Aldehyde
RCH2OH RCHOCrO3
CH3-CH=CH-CH2OH CH3-CH=CH-CHOPCC
H OH
Carboxylicacid
R-CH-R’ R-C-R’CrO3OH
Sec- alcohol KetoneO
3CH3-CH2-CH2-OH + PCl3 → 3CH3-CH2-CH2-Cl + H3PO3
C2H5OH CH2=CH2+H2O443KH2SO4
CH3CHCH3 CH3-CH=CH2+H2O440K
85%H3PO4OH
CH3
CH3CH3-C-OH CH3-C-CH3+H2O
358K20%H3PO4 CH2
CO + 2H2 CH3OH200-300 atm
573-673 K
ZnO-Cr2O3
C12H22O11 + H2O C6H12O6 + C6H12O6Invertase
C6H12O6 2C2H5OH + 2CO2Zymase
Glucose Fructose
Compound
CH3-OH
Common name IUPAC name
Methyl alcohol Methanol
CH3-CH2-CH2-OH
CH3-CH2-CH2-CH2-OH
HO-H2C-CH2-OH
CH3-CH2-CH2-CH2-OH
n-Propyl alcohol Propan-1-ol
Isopropyl alcohol Propan-2-ol
n-Butyl alcohol Butan-1-ol
sec-Butyl alcohol Butan-2-ol
Isobutyl alcohol 2-Methylpropan-1-ol
tert-Butyl alcohol 2-Methylpropan-2-ol
CH3-CH-CH3OH
CH2-CH-CH2OHOH OH
CH3-CH-CH2-OHCH3
Ethylene glycol
Glycerol
Ethane-1,2-diol
Propane -1,2,3-triol
CH3-C-OHCH3
CH3
Chemical Proper�es
It is a white crystalline compound that has a dis�nc�ve odour
Alcohols, Phenols and EthersStructure
Monohydric Phenol
Part - 2
NomenclatureClassifica�on
Dihydric Phenol
Trihydric Phenol
Electrophilic aroma�c subs�tu�on Reimer-Tiemann Reac�on
Oxida�on
Reac�on of Phenol with zinc dust
Kolbe’s reac�on
Phenols
1) Nitra�on
2) Halogena�on
OH OH
136 pm
1090
::
OH OHCH3
OHOH
OH
OHOH
OHOH
CH3
OHOH
OH
CH3
OH
OH
OH
CH3
OH
OH
PhenolPhenol
CatecholBenzene-1,2-diol
Hydroquinone or quinolBenzene-1,4-diol
o-Cresol2-Methylphenol
m-Cresol3-Methylphenol
p-Cresol4-Methylphenol
Prepara�on
From Haloarenes
From Benzenesul-phonic acid
From Diazonium salts
From Cumene
OH O-Na+ OH
+NaOH
+N2+HCl
623 K300 atm
HCl
NH2-+
N2Cl OHNaNO2+HCl Warm
H2O
O-Na+ OHOleum (i) NaOH
(ii) H⁺
+CH3COCH3
CH3-CHCH3
CH3-C-O-O-HCH3
OHO2
H2OH⁺
1. Boiling Point- * Phenols have higher boiling points in comparison to other organic compounds having equal molecular masses
2. Solubility- * The hydroxyl groups are responsible for the solubility of phenol in water * The solubility of phenol decreases with the increase in the size of the aryl group
Physical Proper�es
H - O - H - O - H - O -
R - O - H - O - H - O - H - O -H H
R
R
R
O OHH
ORH O
R
OHNO2
OH
NO2
OHDilute HNO3
o-Nitrophenol
+
p-Nitrophenol
OHBr
OH
Br
OHBr2 in CS2
Minor
+
Major
273 K
OH ONa OHCOOHNaOH
2-Hydroxybenzoic acid(salicylic acid)
(i) CO2(iI) H⁺
OHCHCl2
O Na⁺CHCl3 + aq NaOH
Intermediate
benzoquinne
Salicylaldehyde
NaOH CHOO Na⁺
H⁺ CHOOH
OH
OH
+ Zn
H2SO4Na2Cr2O7
+ ZnO
O
O
Phenol
Benzene diazonium chloride
Aniline
Cumene hydroperoxide
Cumene
Chemical Proper�es
Cleavage of C–O bond in ethers
Nitra�on
Friedel-Cra�s reac�on
Halogena�on
Electrophilic subs�tu�on
Alcohols, Phenols and EthersStructure
Symmetrical Ethers
Part - 3
NomenclatureClassifica�on
Unsymmetrical Ethers
1. Miscibility Miscibility with water resembles those of alcohols of the same molecular mass
1. By dehydra�on of alcohol
2. Williamson synthesis
2. Boiling Points * Lower than alcohols * This is due to the presence of hydrogen bonding in alcohols which is absent in ethers
Prepara�on Physical Proper�es
Methoxymethane
H
H HH
H141 pm
sp3 hybridised
111.70C
:O:
CH
CH3 CH2 - O - CH2 CH3diethyl ether tetrahydrofuran
methyl phenyl ether
O
O CH3
CH3CH2OH
CH2=CH2
C2H5OC2H5
H2SO4443 K
H2SO4413 K
R-X+R’-ONa⁺::
R-O-R’+Na X::
:OH
:
:O Na
:
:O-R
:
+ NaOH R - X
+-
R:O:
RH O H:
:
R-OH+HX → R-X + H2O
+H-X
R-O-R + HX → RX + R-OH
O-R OH
+R-X
OCH3NO2
OCH3
NO2
OCH3H2SO4
2- Nitroanisole(Minor)
4- Nitroanisole(Major)
+HNO3
OCH3CH3
OCH3
CH3
OCH3
+CH3Cl
2- methoxy-toluene(Minor)
Methyl chloride
4- methoxy-toluene(Major)
+CS2
Anhyd. AlCl3
OCH3COCH3
OCH3
COCH3
OCH3
+CH3COCl
2- methoxy-acetophenone
(Minor)
Ethanoylchloride
4- methoxy-acetophenone
(Major)
+Anhyd. AlCl3
OCH3Br
OCH3
Br
OCH3
Br2 in
p - Bromoanisole(major)
+Ethanoic acid
o - Bromoanisole(minor)
:OR
:
+OR
:
↔-
+OR
:
↔-
OR
:
↔-
OR
:
↔
+
Compound
CH3OCH3
Common name IUPAC name
Dimethyl ether Methoxymethane
C2H5OC2H5 Diethyl ether Ethoxyethane
CH3OCH2CH2CH3 Methyl n-propyl ether 1-Methoxypropane
C6H5OCH3 Methyl phenyl ether(Anisole)
Methoxybenzene(Anisole)
C6H5OCH2CH3 Ethyl phenyl ether(Phenetole)
Ehoxybenzene
C6H5O(CH2)6-CH3
CH3-O-CH2-CH2-OCH3
Heptyl phenyl ether 1-Phenoxyheptane
Methyl isopropyl ether 2-MethoxypropaneCH3O-CH-CH3CH3
Phenyl isopentyl ether 3-Methylbutoxybenzene
1,2-Dimethoxyethane
2-Ethoxy--1,1-dimethylcyclohexane
C6H5-O-CH2-CH2-CH-CH3CH3
H3C CH3OC2H5
Ether
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