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Chapter
Alcohol and Ether
Nomenclature of Ethers
The functional group of ether is an oxygen atom bonded to two carbon atoms
R—O—R
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The simplest ether is dimethyl ether, CH3OCH3
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The most common ether is diethyl ether CH3CH2OCH2CH3
Although ethers can be named according to the IUPAC system, chemists almost invariably use common names for
low-molecular-weight ethers.
◦
◦
E.g
Common names are derived by listing the alkyl groups bonded to oxygen in alphabetical order and adding
the word "ether”.
Alternatively, name one of the groups on oxygen as an alkoxy group (RO- ).
Name the following molecule
E.g Use bond-line to draw
Isopropyl methyl ether
4-ethoxy-2-methyl-1-hexene
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Substitution of Alcohols (ROH  RX)
CH3Cl
+
CH3OH +
-
OH  CH3OH
Cl-
 CH3Cl
+
+
Cl-
OH

-

Must convert into a weaker base, in the protonated form (
ROH + NaCl  NR (no LG)
ROH + HCl  RCl + H2O
ROH + HBr  RBr + H2O
ROH + HI  RI + H2O
OH is strongly basic, unstable, not a good LG
)
Explain why (S)-2-butanol forms a racemic mixture when it is heated in aqueous sulfuric acid?
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E.g
Predict the product and provide a mechanism
Elimination reactions of Alcohols
 Aka dehydration of alcohol  lost of H2O
 Required strong acid catalyst
 Formation of alkene follows Zaitsev’s rule: More substituted alkene is the major product
 More stable carbocation will be formed faster
Benzylic/allylic/3o ROH > 2oROH >> 1oROH
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Ether is also obtained; it is the product of a competing SN2 reaction
E.g
Give the major product formed when each of the following alcohols is heated in presence of H2SO4
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Oxidation of Alcohols
Oxidation: increases # C-O bonds and decreases the # of C-H bonds
Reduction: decreases # C-O bonds and increases the # C-H bonds
Common reagents: chromic acid, chromate salt, dichromate salt, permanganate
 Oxidation of a 1° alcohol to a carboxylic acid is commonly carried out using potassium dichromate, K2Cr2O7, in
aqueous sulfuric acid.
 Or using pyridium chlorochromate (PCC) as the oxidizing agent in an anhydrous solvent
◦ Oxidation of a 2° alcohol and cyclic alcohol gives a ketone.
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 Tertiary alcohols are resistant to oxidation
Consider the following reaction
Predict the product(s)
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