Buha Harnish 130270105003 Chemical Engineer

Nitration of Methyl Benzoate

Multistep Synthesis 50% 50% C B A Yield = 25%

Ortho Meta Para Ortho Meta Para

Nomenclature 6 2 3 5 4

Nucleophilic Aliphatic Substitution Electrophilic Aromatic Substitution

The electrophile REPLACES H+ ARENE SUBSTITUTION E+ + H+ The electrophile REPLACES H+

Mechanism E - Y

E - Y Mechanism + H+

Charge o and p

Reaction Coordinate

Nitration of Benzene Nitrobenzene

Nitration Reagent HONO2 + 2 H2SO4 NO2+ + H3O+ + 2 HSO4- Nitronium Ion

Multiple Substituents G Second Group. Where go? How fast?

Nitration of Toluene HNO3 63% 3% 34%

ORTHO + + + META + + + PARA + + +

Electron donating groups favor reaction ORTHO and PARA.

Nitration of (trifluoromethyl)benzene HNO3 H2SO4 6% 91% 3%

Electron Withdrawing group + charge here bad

Ortho + + + Meta + + + Para + + +

Electron Withdrawing Groups are Meta Directors and DEACTIVATING Meta Product

Ortho-Para Directors Very Activating -NH2 -NHR -OH -OR O -NHCR O -OCR

Deactivating -Halogens Ortho-Para Directors Activating -R Activating

Meta Directors O -SO3H -CR O -NO2 -COH -CN

Main Reaction meta Side Products

Procedure 1. Dissolve methyl benzoate in H2SO4 2. Mix HNO3 and H2SO4 at 0oC 3. Add HNO3 / H2SO4 dropwise to methyl benzoate at 0oC

Procedure 4. Let stand at room temperature 10 minutes 5. Pour onto ice

Filter

Wash Recrystallize from methanol Dry Weigh m.p.