Nitration of Methyl Benzoate
Introduction:
In this experiment, you will do an aromatic nitration experiment. You will use methyl benzoate
as the starting material. Because methyl benzoate only has one group on the benzene ring, you
have the possibility of three products: ortho-, meta-, and para-. You will use melting point as the
primary method to determine the identity of your product.
Reaction Scheme:
C
OCH
3
O
C
OCH
3
O
NO
2
HNO
3
, H
2
S O
4
i c e b a t h
M e t h y l B e n z o a t e M e t h y l X - n i t r o b e n z o a t e
Precautions:
Nitric acid is a strong acid and a powerful oxidizing agent. Sulfuric acid is a strong acid. Wear
gloves. If you spill any of these, wipe them up with wet paper towels. If you spill these on you,
wash the affected areas with lots and lots of soap and water.
Procedure:
Reaction:
Place 3 mL of concentrated sulfuric acid in a 50 mL Erlenmeyer flask, and cool it in an ice-water
bath for about 10 minutes. Also, prepare a mixture of 1 mL of concentrated nitric aicd and 1 mL
of concentrated sulfuric acid in a test-tube, and cool it in your ice-water bath. Measure out 1.4
grams of methyl benzoate into another test tube (how will you do this?), and use a pipette to add
it slowly to the sulfuric acid, while swirling the flask. Keeping the Erlenmeyer flask in the ice-
bath, add the cold mixture of nitric and sulfuric acids dropwise to the Erlenmeyer flask, while
swirling the flask. After you have added the nitric and sulfuric acids, continue to swirl the flask
occasionally over the next 10-15 minutes.
Product Isolation:
Pour the reaction mixture, with stirring, into about 10 grams of ice in a small beaker. The product
should precipitate as you stir the mixture. Collect the product by suction filtration, and wash it
thoroughly with three small portions of ice-cold water. Remember to release the suction, add the
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