Nitrating Methyl Benzoate: Electrophilic Aromatic ... - Franklin College

Nitrating Methyl Benzoate: Electrophilic Aromatic Substitution
(d) The structure of my product is:
O
NO2
C
Methyl m-nitrobenzoate
OCH3
2. The resonance forms for the arenium ion formed during this reaction are as follows:
O
C
+
OCH3
NO2
+
O
C
OCH3
NO2
Methyl m-nitrobenzoate
OCH3
3. The first nitration proceeds much faster than the second two because the first –NO2 group to be added is
added to the isolated toluene. The methyl group on the benzene ring is an activating group. It causes the
benzene ring to be more electron rich and thus, have a high reactivity. –CH3 is an ortho-para activator. So,
the first –NO2 group adds to the toluene in the para-position in order to avoid steric crowding from the
methyl group. The toluene has now been converted to para- nitrotoluene. The –NO2 group that is now on
the benzene ring is a deactivating group, and causes the benzene ring to be not nearly as reactive as it was
before the first –NO2 group was added. Thus, the second and third nitrations occur much more slowly
than does the first one.
O
C
+
NO2