1. Examples
(a.)
(b.)
(c.)
(d.)
(e.)
(f.)
(g.)
Chemistry 212 Spring 2012
Reactions of Substituted Aromatic Compounds – Only organic products given
Reactions
C
N
+ Cl Cl
FeCl
3
Cl
C
N
Relative
Rates
1.0 X 10 -3
NH
2
+ Cl Cl
FeCl
3
Cl
NH
2
+
Cl
NH
2
3.0 X 10
6
Cl
CF
3
CF
3
+ Cl Cl
FeCl
3
CH
3
+ Cl Cl
O
C
+
CH
3
Cl Cl
FeCl
FeCl
3
3
O
C
N
H
CH
3
+
Cl Cl
FeCl
3
Cl
Cl
CH
3
+
O
C CH
3
Cl
Cl
O
C
N
H
CH
3
+
Cl
CH
3
O
C
N
H
CH
3
4.0 X 10
-4
1.5 X 10
1
1.5 X 10 -3
3.0 X 10
2
Cl
+
Cl Cl
FeCl
3
1
(Rate Standar d)

2. Analysis of Examples: a. List reactions in (1.) above according to decreasing reaction rate.
2 b. Group the reactions in (1.) above according to similarities in reaction pattern.
Aromatic Compounds-2 c.
How are the groupings of reactions in 2.a. related to those in 2.b.? Provide your warrant. d.
What do the outcomes of reactions with rates faster than that of benzene (unsubstituted standard rate =1) have in common? Provide your warrant. e.
What common characteristics are there among the structures of the reactants with rates faster than that of benzene (unsubstituted standard rate
=1)? Provide your warrant.

Aromatic Compounds-2 3 f.
What do the outcomes of reactions with rates slower than that of benzene (unsubstituted standard rate =1) have in common? Provide your warrant. g.
What common characteristics are there among the reactants with rates slower than that of benzene (unsubstituted standard rate =1)? Provide your warrant. h.
Write a mechanism (using arrows) for the formation of one product from each reaction listed in 2 b. above. i.
Now try to devise mechanistic arguments to explain:
(1.) The variation in the relative rates in 2.a.
(2.) The variation of reaction patterns in the reactions in 2.b.

4
O
O
Aromatic Compounds-2
1.
Predict the products of the following rxns. Provide the warrant for your predictions.
CH
3
C
..
NH
(b.)
+
N
+
O
H
2
C
CH
CH
3
H
2
SO
4
CH
3
N
C
(a.) + HNO
3
(c.)
H
2
SO
4
CH
3
O
O Br
N
(d.)
+
O
S
O
H
2
SO
4
(e.)
+ CH
3
Br
AlBr
3
(f.)
C
CH
3
+
+
CH
3
CH
3
SO
3
C
C
O
O
H
2
SO
4
H
2
SO
4
S . .
..
O
CF
3 O
CH
3
(g.)
+ Cl Cl
S
OH
O
FeBr
3
(h.) O +
HNO
3
H
2
SO
4
(i.)
+
CH
3
C Cl
AlCl
3
2.
Which of the following compounds would be most reactive (give a higher rate) in ring nitration? Which would be least reactive? Provide a warrant with backing based on electron energies.
NH
2
CH
3
O
C
CH
3
CH
3
C
O
NH
(a.) (b.) (c.) (d.)
3.
Which compound in (2.) above would yield the highest percentage of meta -Nitro product?
(e.)

Aromatic Compounds-2
4.
Circle the major product(s) of the following rxn and provide the warrant for your choice:
O
NH C
Br
2
FeBr
3
5
NH C
O
NH C
O
NH C
O
Br
(a.)
NH C
O Br
(b.)
NH C
O
(c.) Br
Br
(d.)
Br
(e.)
5.
Which of the following reactions would yield p-Isopropylbromobenzene? Provide your warrant.
Br
Br
O
H
Br
(a.)
+
H
2
SO
4
(b.) + H
2
SO
4
(c.) +
6. Which one(s) of the following is(are) NOT meta -directing when attached to a benzene ring? Provide your warrant.
H
H
N
O
C
CH
3
O
N
+
O
CH
3
CH
3
N
+
CH
3
N
C
O
C
O
(a.) (b.) (c.) (d.) (f.)
Cl
AlCl
3