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Alcohols and Ethers can be regarded as derivatives of water in which one or two of the H atoms has been replaced by an alkyl group

Saturated molecules are sp3

hybridized

OH H

104.5o

0.96 AoWater, H2OO

C H

108.5o

0.96 Ao

Methanol, CH3OH

HH

H

1.43 Ao

OC C

111.7o

Methoxymethane, CH3OCH3

HH

H

1.43 Ao

H

HH

109.5o1.10 Ao

Rantai utama adalah rantai karbon terpanjang yang mengandung –OH

Nama alkohol dinamai dengan nama alkana dengan mengganti akhiran -a dengan -ol

Posisi gugus –OH diberi nomor

CH3OH : metanol = metil alkohol

CH3CH2OH : etanol = etil alkohol

CH3CH2CH2OH : 1-propanol = n-propil alkohol   : 2-propanol = isopropil alkohol

: 2-metil-1-propanol = isobutil alkohol

OH

CH3CH CH3

Letak gugus -OH menunjukkan derajat alkoholnya

ALKOHOL 1 ALKOHOL 2 ALKOHOL 3

H

C OHH3C

H

CH3

C OHH3C

H

CH3

C OHH3C

CH3

Primary (1o) AlcoholSecondary (2o) Alcohol

Tertiary (3o) Alcohol

Polyhydroxy alcohols are alcohols that possess more than one hydroxyl group

CH2 CH2

HO OH

1,2-Ethanediol (ethylene glycol)

1,2-Propanediol (propylene glycol)

1,2,3-Propanetriol (glycerol)

CH CH2

OH

CH3

HO

CH CH2

OH

CH2

HOHO

Extremely Toxic

Harmless

Methanol and Ethanol are classed as Polar Molecules (Hydrophilic)

OH3C H

Electronegativity of oxygen causes an unsymmetrical distribution of charge

R

OH

HO

R

R

OH

Alcohols are found to have much higher boiling point than those of alkanes or haloalkanes in homologues series

H

OH

HO

H

H

OH

They are Soluble in Water

Hyd

rog

en

B

on

din

g

As R-group increases in size, so does the solubility in non-polar solventsAs the number –OHs increases so does solubility in waterBpt increase with chain length and number of –OHs Methanol, CH3OH

- Solvent in varnishes, paint- Racing Car Fuel (easy to put out flames)- Highly Toxic

Ethanol, CH3OH

-Drinking Alcohol

- 50% Ethanol is flammable

C O

H

H

H

C

H

H

H C O

H

H

H

C

H

H

C

H

H

C

H

H

C

H

H

H

Hydrophobic end

Hydrophilic end1-PentanolEthanol

Alcohols are very weak Acids

R O H

H

O H R O +

H

O HH

AlcoholAlkoxide

Relative Acidity ; H2O > ROH > C CR H > RH

CH3CH2OH + Na CH3CH2 O Na + H2

Vigorous Reaction

2 2 2

Hidrasi katalisis dari alkena (proses industri) Fermentasi gula menggunakan

katalis enzim

CH3CH2OH

H

H

H

H

H3PO4 , 300C

H2O

C6H12O6enzim

2CH3 CH2OH + 2CO2

Beer, 3-9% Wine, 11-13% Whisky, 40-45% Vanilla Extracts, 35% Night Nurse, 25% Listerine, 25%

Phenols are stronger acids than alcohols

OH OH

pKa = 18 pKa = 10

OHO O O

Resonance Stabilised Phenoxide anion

ETHERS, RO-ORCH3CH2 O CH2CH3

CH3CH2 O

H3C O

Ethoxy group

Methoxy group

Diethyl Ether

1-Propoxypropane

Methoxybenzene (anisole)

Methoxycyclohexane

OTetrahydrofuran (THF) O

OFuran Pyran

Cyclic Ethers

H3CO O

OCH3

Boiling point are similar to alkanes

No H-bonding to one another Soluble in water (H-bonding to

water) Polar Flammable – Ether can cause

flash fires Low Reactivity – Make Good

Reaction Solvents