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Table of Ka Values
Acid-Dissociation Constants of
Representative Alcohols
Alcohol
Structure
methanol
ethanol
2-chloroethanol
2-2-trichloroethanol
isopropyl alcohol
t-butyl alcohol
cyelohexanol
phenol
Comparison with
other acids
water
acetic acid
hydrocholric acid
Ka
pKa
METHODS FOR THE SYNTHESIS OF ALCOHOLS (to date)
ELECTROPHILIC AND NUCLEOPHIC CARBON
Methylmagnesium bromide Methyl lithium
Methyl chloride
TYPICAL ELECTROPHILES
Methyl chloride
acetone
Alcohols, carbonyl compounds and carboxylic acids:
REDUCTION
Reduction: Addition of H2 (or H-), loss of O or O2; loss of X2
Primary alcohol
Aldehyde
Carboxylic acid
must convert OH to
leaving group
Secondary alcohol
Ketone
must convert OH to
leaving group
Teritiary alcohol
Lithium aluminium Sodium borohydride
hydride
aldehyde
reduces
Comparison of
Reducing Agents
ketone
reduces
ester
Acid (anion)
ease of
reduction
• LiAlH4 is stronger.
• LiAlH4 reduces more
stable compounds
which are resistant to
reduction.