ETHERS

R-O-REthersEthers

C2H5-O-C2H5

Diethyl ether

Diethyl Ether

Check the “fine print”

PEROXIDES!!PEROXIDES!!

R-O-RO2

R-O-O-R RCH-OR

OOH

EXPLOSIVE

Ethyl methyl ether

methoxy group

CH3CHCH2CH3

OCH3

What is the name of this compound?

2-methyoxybutane

Ethylene Oxide

O

Tetrahydrofuran

OFuran

THF

Dioxane

Dioxin Dioxin

18-Crown-6

K+

X-

Williamson Ether SynthesisWilliamson Ether SynthesisWilliamson Ether SynthesisWilliamson Ether Synthesis

ROH

NaRONa

RONa + R’X ROR’

Nucleophilic Substitution Reaction

Why is this compound discussed on TV news?

How could you make this ether?

CH3-C-OH

CH3

CH3

CH3-C-O

CH3

CH3

KK

CH3IC-O-CH3

CH3

CH3

CH3

CH3OHNa CH3ONa

C CH2

CH3

CH3

Dimethyl sulfate

RONaCH3O-SO2-OCH3

R-O-CH3

Cleavage of EthersCleavage of Ethers

R-O-R 2 RBr HBr

CH3CH2

OCH3CH2

CH3CH2

OCH3CH2

H+

Br-

CH3CH2Br + CH3CH2OH

HBr

CH3CHCH2CH3

OCH3

EXAMPLE

CH3CHCH2CH3

Br

CH3Br+

HBr

EPOXIDESEPOXIDES

RCO3H

RO- + R’X R-O-R’

C CH

CH3

CH3H

Br

HO

Br2

H2O

C C

CH3H CH3

H

O

NaOH

RMgX + RCH2CH2OH

CH3OCH2CH2OH

CH3ONa +

CH3ONa +

?CH3OH

Unsymmetrical Epoxide

CH3ONa +CH3OH

C CH

H

OCH3

OH

CH3CH3

Basic

Least Hindered

CH3OH +

ACIDIC CONDITIONSACIDIC CONDITIONS

??H+

H+

C C

O

HH

CH3CH3

H

C C

OH

HH

CH3

CH3

C C

OH

HHCH3O

CH3

CH3

Most Substituted

CH2 CH2

O

CH2 CH2

O

H

+

OH H

CH2 CH2

OH

HO

H3O+

HCl

What is the product of this reaction?

HCl

C C

OH

HHCl

CH3

CH3

Summary

Nomenclature

Williamson Ether Synthesis

Cleavage of Ethers

Epoxides

RONa + R'X ROR' + NaX

ROR' + HBr RBr + R'Br

CH2CCH3

CH3O

CH3ONaCC

OCH3

HHHO

CH3CH3

CH2CCH3

CH3O

HClCC

OH

Cl HH

CH3CH3