Nitration of Methyl Benzoate
COOCH3
COOH
CH3OH
H2SO4
COOCH3
COOCH3
HNO3, H2SO4
NO2
Multistep Synthesis
A
50%
B
50%
Yield = 25%
C
Nucleophilic Aliphatic Substitution
HCl
(CH3)3COH
(CH3)3Cl
Electrophilic Aromatic Substitution
H
+
NO2
+
NO2
ARENE SUBSTITUTION
E
H
E+
+ H+
The electrophile REPLACES H+
H
E-Y
H
E
+
E-Y
H
H
E
+
H
H
E
E
H
+
+
+
E
+ H+
E
H
H
E
H
E
+
+
+
E
Nitration of Benzene
NO2
HNO3
H2SO4
Nitrobenzene
Nitration Reagent
HONO2 + 2 H2SO4
NO2+ + H3O+ + 2 HSO4-
Nitronium Ion
H
NO2
H
+
NO2
+
NO2
+ H+
Multiple Substituents
G
G
G
G
Second Group. Where go? How fast?
Nitration of Toluene
CH3
HNO3
CH3
CH3
CH3
NO2
NO2
NO2
63%
3%
34%
ORTHO
CH3
CH3
+
CH3
NO2
NO2
NO2
H
H
H
+
META
CH3
+
CH3
CH3
+
+
NO2
H
PARA
NO2
NO2
H
H
+
CH3
CH3
CH3
+
+
H
NO2
+
H
NO2
H
NO2
Electron donating groups favor
reaction ORTHO and PARA.
Electron Donating
G
Ortho
Para
Nitration of (trifluoromethyl)benzene
CF3
HNO3
H2SO4
CF3
CF3
CF3
NO2
NO2
6%
91%
NO2
3%
Electron Withdrawing group
CF3
+ charge
here bad
Ortho
CF3
+
CF3
CF3
H
NO2
+
Meta
H
H
CF3
NO2
+
CF3
CF3
+
+
H
NO2
+
CF3
Para
NO2
H
H
NO2
NO2
CF3
CF3
+
+
H
NO2
+
H
NO2
H
NO2
Electron Withdrawing Groups are
Meta Directors and DEACTIVATING
Electron
Withdrawing
Group
Z
Meta Product
Main Reaction
COOCH3
COOCH3
HNO3, H2SO4
meta
NO2
Side Products
COOCH3
COOCH3
COOCH3
NO2
O2N
NO2
NO2
Procedure
1. Dissolve methyl
benzoate in H2SO4
2. Mix HNO3 and
H2SO4 at 0oC
3. Add HNO3 / H2SO4
dropwise to methyl
benzoate at 0oC
4. Let stand at room
temperature 10
minutes
5. Pour onto ice
Filter
Wash
Recrystallize from
methanol
Dry
Weigh
m.p.