Nitration of Methyl Benzoate
COOCH3
HNO3, H2SO4
COOCH3
NO2
COOCH3COOHCH3OH
H2SO4
Multistep Synthesis
A B C50% 50%
Yield = 25%
(CH3)3COH (CH3)3ClHCl
Nucleophilic Aliphatic Substitution
NO2+
+
H NO2
Electrophilic Aromatic Substitution
ARENE SUBSTITUTION
H EE+
+ H+
The electrophile REPLACES H+
H E - Y H E
+
H E - Y H E
+
H E
+
H E
+
H E
+
E
+ H+
H E
+
H E
+
H E
+
Nitration of BenzeneNO2
HNO3
H2SO4
Nitrobenzene
Nitration Reagent
Nitronium Ion
HONO2 + 2 H2SO4 NO2+ + H3O+ + 2 HSO4
-
HNO2
+ H NO2
+
NO2
+ H+
Multiple SubstituentsG
G G
G
Second Group. Where go? How fast?
Nitration of TolueneCH3
CH3NO2
CH3
NO2
CH3
NO2
HNO3
63% 3% 34%
CH3NO2
H
CH3NO2
H
CH3NO2
H+
+ +
CH3
NO2
H
CH3
NO2
H
CH3
NO2
H
CH3
NO2H
CH3
NO2H
CH3
NO2H
+
+
+
+ ++
ORTHO
META
PARA
G
Electron donating groups favorreaction ORTHO and PARA.
Electron Donating
Ortho
Para
CF3
Nitration of (trifluoromethyl)benzene
HNO3
H2SO4
CF3
NO2
CF3
NO2
CF3
NO2
6% 91% 3%
CF3
Electron Withdrawing group
+ chargehere bad
CF3HNO2
CF3H
NO2
CF3H
NO2
CF3
H
NO2
CF3
H
NO2
CF3
H
NO2
CF3
H NO2
CF3
H NO2
CF3
H NO2
Ortho
Meta
Para
++ +
+
+
+
+ ++
Z
Electron Withdrawing Groups areMeta Directors and DEACTIVATING
ElectronWithdrawingGroup
Meta Product
COOCH3
HNO3, H2SO4
COOCH3
NO2
Main Reaction
Side Products
meta
COOCH3NO2
NO2
COOCH3 COOCH3
NO2O2N
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 roomtemperature 10minutes
5. Pour onto ice
Filter
Wash
Recrystallize frommethanol
Dry
Weigh
m.p.