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Nitration of Methyl Benzoate COOCH 3 HNO 3 , H 2 SO 4 COOCH 3 NO 2 COOCH 3 COOH CH 3 OH H 2 SO 4

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Page 1: Nitration of Methyl Benzoate - University of Illinois Archives Archives/1505050... · Z Electron Withdrawing Groups are Meta Directors and DEACTIVATING Electron Withdrawing Group

Nitration of Methyl Benzoate

COOCH3

HNO3, H2SO4

COOCH3

NO2

COOCH3COOHCH3OH

H2SO4

Page 2: Nitration of Methyl Benzoate - University of Illinois Archives Archives/1505050... · Z Electron Withdrawing Groups are Meta Directors and DEACTIVATING Electron Withdrawing Group

Multistep Synthesis

A B C50% 50%

Yield = 25%

Page 3: Nitration of Methyl Benzoate - University of Illinois Archives Archives/1505050... · Z Electron Withdrawing Groups are Meta Directors and DEACTIVATING Electron Withdrawing Group

(CH3)3COH (CH3)3ClHCl

Nucleophilic Aliphatic Substitution

NO2+

+

H NO2

Electrophilic Aromatic Substitution

Page 4: Nitration of Methyl Benzoate - University of Illinois Archives Archives/1505050... · Z Electron Withdrawing Groups are Meta Directors and DEACTIVATING Electron Withdrawing Group

ARENE SUBSTITUTION

H EE+

+ H+

The electrophile REPLACES H+

Page 5: Nitration of Methyl Benzoate - University of Illinois Archives Archives/1505050... · Z Electron Withdrawing Groups are Meta Directors and DEACTIVATING Electron Withdrawing Group

H E - Y H E

+

Page 6: Nitration of Methyl Benzoate - University of Illinois Archives Archives/1505050... · Z Electron Withdrawing Groups are Meta Directors and DEACTIVATING Electron Withdrawing Group

H E - Y H E

+

H E

+

H E

+

H E

+

E

+ H+

Page 7: Nitration of Methyl Benzoate - University of Illinois Archives Archives/1505050... · Z Electron Withdrawing Groups are Meta Directors and DEACTIVATING Electron Withdrawing Group

H E

+

H E

+

H E

+

Page 8: Nitration of Methyl Benzoate - University of Illinois Archives Archives/1505050... · Z Electron Withdrawing Groups are Meta Directors and DEACTIVATING Electron Withdrawing Group
Page 9: Nitration of Methyl Benzoate - University of Illinois Archives Archives/1505050... · Z Electron Withdrawing Groups are Meta Directors and DEACTIVATING Electron Withdrawing Group

Nitration of BenzeneNO2

HNO3

H2SO4

Nitrobenzene

Page 10: Nitration of Methyl Benzoate - University of Illinois Archives Archives/1505050... · Z Electron Withdrawing Groups are Meta Directors and DEACTIVATING Electron Withdrawing Group

Nitration Reagent

Nitronium Ion

HONO2 + 2 H2SO4 NO2+ + H3O+ + 2 HSO4

-

Page 11: Nitration of Methyl Benzoate - University of Illinois Archives Archives/1505050... · Z Electron Withdrawing Groups are Meta Directors and DEACTIVATING Electron Withdrawing Group

HNO2

+ H NO2

+

NO2

+ H+

Page 12: Nitration of Methyl Benzoate - University of Illinois Archives Archives/1505050... · Z Electron Withdrawing Groups are Meta Directors and DEACTIVATING Electron Withdrawing Group

Multiple SubstituentsG

G G

G

Second Group. Where go? How fast?

Page 13: Nitration of Methyl Benzoate - University of Illinois Archives Archives/1505050... · Z Electron Withdrawing Groups are Meta Directors and DEACTIVATING Electron Withdrawing Group

Nitration of TolueneCH3

CH3NO2

CH3

NO2

CH3

NO2

HNO3

63% 3% 34%

Page 14: Nitration of Methyl Benzoate - University of Illinois Archives Archives/1505050... · Z Electron Withdrawing Groups are Meta Directors and DEACTIVATING Electron Withdrawing Group

CH3NO2

H

CH3NO2

H

CH3NO2

H+

+ +

CH3

NO2

H

CH3

NO2

H

CH3

NO2

H

CH3

NO2H

CH3

NO2H

CH3

NO2H

+

+

+

+ ++

ORTHO

META

PARA

Page 15: Nitration of Methyl Benzoate - University of Illinois Archives Archives/1505050... · Z Electron Withdrawing Groups are Meta Directors and DEACTIVATING Electron Withdrawing Group

G

Electron donating groups favorreaction ORTHO and PARA.

Electron Donating

Ortho

Para

Page 16: Nitration of Methyl Benzoate - University of Illinois Archives Archives/1505050... · Z Electron Withdrawing Groups are Meta Directors and DEACTIVATING Electron Withdrawing Group

CF3

Nitration of (trifluoromethyl)benzene

HNO3

H2SO4

CF3

NO2

CF3

NO2

CF3

NO2

6% 91% 3%

Page 17: Nitration of Methyl Benzoate - University of Illinois Archives Archives/1505050... · Z Electron Withdrawing Groups are Meta Directors and DEACTIVATING Electron Withdrawing Group

CF3

Electron Withdrawing group

+ chargehere bad

Page 18: Nitration of Methyl Benzoate - University of Illinois Archives Archives/1505050... · Z Electron Withdrawing Groups are Meta Directors and DEACTIVATING Electron Withdrawing Group

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

++ +

+

+

+

+ ++

Page 19: Nitration of Methyl Benzoate - University of Illinois Archives Archives/1505050... · Z Electron Withdrawing Groups are Meta Directors and DEACTIVATING Electron Withdrawing Group

Z

Electron Withdrawing Groups areMeta Directors and DEACTIVATING

ElectronWithdrawingGroup

Meta Product

Page 20: Nitration of Methyl Benzoate - University of Illinois Archives Archives/1505050... · Z Electron Withdrawing Groups are Meta Directors and DEACTIVATING Electron Withdrawing Group

COOCH3

HNO3, H2SO4

COOCH3

NO2

Main Reaction

Side Products

meta

COOCH3NO2

NO2

COOCH3 COOCH3

NO2O2N

Page 21: Nitration of Methyl Benzoate - University of Illinois Archives Archives/1505050... · Z Electron Withdrawing Groups are Meta Directors and DEACTIVATING Electron Withdrawing Group

Procedure

1. Dissolve methyl benzoate in H2SO4

2. Mix HNO3 and H2SO4 at 0oC

3. Add HNO3 / H2SO4 dropwise to methyl benzoate at 0oC

Page 22: Nitration of Methyl Benzoate - University of Illinois Archives Archives/1505050... · Z Electron Withdrawing Groups are Meta Directors and DEACTIVATING Electron Withdrawing Group

4. Let stand at roomtemperature 10minutes

5. Pour onto ice

Page 23: Nitration of Methyl Benzoate - University of Illinois Archives Archives/1505050... · Z Electron Withdrawing Groups are Meta Directors and DEACTIVATING Electron Withdrawing Group

Filter

Page 24: Nitration of Methyl Benzoate - University of Illinois Archives Archives/1505050... · Z Electron Withdrawing Groups are Meta Directors and DEACTIVATING Electron Withdrawing Group

Wash

Recrystallize frommethanol

Dry

Weigh

m.p.