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284 Chapter 8
Copyright © 2017 Pearson Education, Inc.
12.
OCH
3
major
OCH
3
minor
−
OCH
3
minor
−
OCH
3
−
OCH
3
+
minor
major
+
+
13.
_
C
NHCH
3
H
C
NHCH
3
H
+
major
minor
O
O
7.
+
+
+
+
+
The five contributors are equally stable and, therefore, contribute equally to the resonance hybrid.
8.
C
O
OCH
2
CH
3
C
O
OCH
2
CH
3
CH
3
CH
2
CH
3
CH
2
+
_
major
minor
9.
minor
(the positive charge is on
a primary allylic carbon)
major
(the positive charge is on
a secondary allylic carbon)
major (the positive charge is on
a secondary allylic carbon)
CH
3
CH CH CH CH CH
2
+
+
CH
3
CH CH CH CH CH
2
+
CH
3
CH CH CH CH CH
2
10.
_
C
O
CH
2
CH
3
C
O
CH
2
CH
3
CH
2
CH
2
_
major
minor
The major contributor has a negative charge on oxygen, which is more stable than a contributor with a
negative charge on carbon.
11.
CH
3
CH C N
CH
3
CH C
minor
major
N
−
−