Ethers, Epoxides and Sulfides

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Chapter 14 Ethers, Epoxides and Sulfides
1. Common names - use alkyl name ether
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2. IUPAC nomenclature - name the most complicated
part as the alkane and add the rest as an
alkoxy substituent (in alkyl name - drop yl
add oxy). Remember the alkoxy name is only a
higher priority than the halides. It is even
lower than the alkyl substiuent.
(actually the S,R enantiomer as drawn)
3. Cyclic ethers a. common names
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b. IUPAC - two ways(!)
Name as an epoxide
Name as an oxirane
Best
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B. Uses 1. solvents - have moderate polarity and
are unreactive (for the most part).
2. feedstock chemicals
3. polymers
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4. biological - well see some more later
Juvenile hormone - prevents maturation of insect
larvae
Phermone for the American cockroach
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5. forming complexes a. 6 electron reagents -
storage
b. crown ethers, etc.
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C. Spectra 1. IR- nothing!! - BUT--if you know O
is present AND there are no CO or O-H
peaks 2. NMR
1H
d 3.5 - 4.0 ppm
d 65 - 90 ppm
13C
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D. Synthesis of ethers 1. Industrial -
bimolecular dehydration a. overall reaction
(Rs must be the same)
b. mechanism
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2. Williamson Synthesis a. overall reaction
NOTE RX really needs to be 1
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3. Oxymercuration-demercuration a. overall
reaction
And so using ROH in place of H2O
b. mechanism issues
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c. examples
E. Reactions of ethers - not many! 1. Cleavage
by strong acids a. overall
b. mechanism
(could be SN1 In some cases)
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c. examples
2. Autoxidation a. overall reaction
b. partial mechanism
Stable free radical
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NOW
heat given off!!!
BE VERY CAREFUL IN STORING ETHERS!!!
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F. Sulfides 1. Nomenclature a. common - drop
ether add sulfide
b. IUPAC - replace alkoxy name with
alkylthio
2. Reactions a. oxidation
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b. preparation - using thiols
c. reactions - substitution (SN2)
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G. Epoxides 1. Preparation a. Reaction of
olefins with peracids
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b. Reaction with halohydrins
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2. Reactions of epoxides - ring strain

• Acid catalyzed ring opening
• general-

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Note orientation
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b. Ring opening under basic conditions
Note orientation
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An aside into the land of bar-be-que!!
Bad reaction
arene oxides
OK reaction
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H. Summary 1. Ethers a. nomenclature
spectroscopy b. preparation i. Williamson
synthesis ii. alkoxymercuration-demecuration
c. reactions i. acid catalysed cleavage ii.
auto-oxidation 2. Sulfides a.
nomenclature b. oxidation reactions to
sulfones, sulfoxides c. preparation - analog to
Williamson synthesis d. sulfides as
nucleophiles
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3. Epoxides - synthesis a. reaction of olefins
with peracids b. cyclization of halohydrins 4.
Epoxides - reactions a. acid catalyzed ring
opening b. nucleophilic ring opening under basic
conditions