Chem 350 Jasperse Ch. 11 Handouts
1
Summary of Alcohol Reactions, Ch. 11.
1
R OH R ONa
Acid-Base
+ HZ
???
+ NaZ
1. Deprotonation by a base.
2. Controlled by relative stability of
RO versus Z .
3. Consider relative electronegativity and
whether either anion is resonance
stabilized.
2
R OH R ONa
Na
• Potassium (K) analogous.
• Key way to convert alcohol to
alkoxide, reactive as SN2 nucleophile
and E2 base.
3
R OH R O R'
1. Na
2. R'-X
• Alkoxide formation-SN2 route to ether
• The electrophile R'-X must be SN2
reactive, preferably 1º with a good
leaving group
4
R H R H
O
Aldehydes
1º Alcohols Only
PCC
OH
H
• Key access to aldehydes, which are
useful for more Grignard chemistry.
• Note difference between PCC and
H2CrO4
• PCC does not react with 2º alcohols
very rapidly
5
R R R R
O
OH
H2CrO4 = Na2Cr2O7, H2SO4 or CrO3/H2O
Ketones
2º Alcohols Only
H2CrO4
H
• Key access to ketones.
• PCC does not react very fast with 2º
alcohols
6
R OH
O
1º Alcohols Only Acids
H2CrO4
R H
OH
H
• Note difference between
• PCC and H2CrO4 when reacting with
1º alcohols.
7
R H R OH
O
O
Acids
Aldehydes
H2CrO4
8
R OH R Br
Mech: Be able to draw!
3º alcohols
HBr
• HI, HCl analogous
• Converts alcohol into a bromide that
can be used in Grignards, E2 reactions
• Cation mechanism
• Usually not method of choice for 1º, 2º
alcohols
