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Chapter 8 289
Copyright © 2017 Pearson Education, Inc.
80.
a.
CH
3
−
C
O
O
The negative charge is shared by two oxygens.
b.
CH
3
CH
2
CH
C
CH
3
O
_
The negative charge is shared by a carbon and an oxygen.
c.
CH
3
_CH CH
3
C
O
C
O
The negative charge is shared by a carbon and two oxygens.
d.
N
−
O
O
The negative charge is shared by a nitrogen and two oxygens.
81.
The stronger base is the less stable base of each pair in Problem 80.
a.
C
O
CH
2
O
CH
3
−
Less stable because the negative charge cannot be delocalized.
b.
_
CH
3
CHCH
2
C
CH
3
O
Less stable because the negative charge cannot be delocalized.
c.
C
O
CHCH
2
C
CH
3
O
_
CH
3
Less stable because the negative charge can be delocalized onto only one
oxygen.
d.
N
−
O
Less stable because the negative charge can be delocalized onto only one
oxygen.
82.
The resonance contributor shown here indicates which nitrogen is most apt to be protonated (the one with
the greatest negative charge) and which nitrogen is least apt to be protonated (the one with the greatest
positive charge).
N
N N
H
N
N
N N
H
N
+
−
most apt to be
protonated
least apt to be
protonated