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Solutions for Reactions of Alcohols
N
H
N
H
O P
O
Cl
Cl
H
N
O P
O
Cl
Cl
N
O
H
P
O
Cl
Cl
P
O
Cl
ClClO
H
23 good leaving group
E2
This product can react with two 
more alcohols to become leaving 
groups in the E2 elimination.
Cyclohexene was formed
without a carbocation
intermediate.
24
O CH2CH3CH3CH2
O HC
H
H
C
H
H
H
H
C
H
H
C
H
H
O
H
CH3CH2 CH2CH3
H C
H
H
C
H
H
O H
O
H
H C
H
H
C
H
H
H
O HC
H
H
C
H
H
H
H
+ H2O
Both mechanisms begin with protonation of the oxygen.
The other mechanism involves another molecule of ethanol acting as a nucleophile, giving substitution.
One mechanism involves another molecule of ethanol acting as a base, giving elimination.
∆ H2O + CH3CH2OCH3 + CH3OCH3 + CH3CH2OCH2CH3CH3CH2OH + HOCH3
25 An equimolar mixture of methanol and ethanol would produce all three possible ethers. The 
difficulty in separating these compounds would preclude this method from being a practical route to any 
one of them. This method is practical only for symmetric ethers, that is, where both alkyl groups are 
identical.
HO Et
HO Et
HO Et
H A
H2SO4
254