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Spectroscopy Problems
67
Copyright © 2017 Pearson Education, Inc.
52.
A.
The absence of an absorption band
7
3000 cm
-
1
eliminates all the structures with an O
¬
H or
N
¬
H bond. Therefore, the following compound is responsible for the spectrum.
OCH
3
OCH
3
B.
The broad absorption band at
∼
3400 cm
-
1
is due to an O
¬
H bond. Therefore, the following
compound is responsible for the spectrum.
OH
C.
The two absorption bands at
∼
3400–3300 cm
-
1
indicate two N
¬
H bonds. Therefore, the following
compound is responsible for the spectrum.
NH
2
D.
The absorption band at
∼
3400–3300 cm
-
1
is due to one N
¬
H bond. Therefore, the following
compound is responsible for the spectrum.
N
H
53.
A.
The two absorption bands at
∼
3400–3300 cm
-
1
indicate two N
¬
H bonds. The doublet at 0.9 ppm
indicates an isopropyl group. Subtracting NH
2
and (CH
3
)
2
CH from the molecular formula leaves
C
2
H
4
. Therefore, this compound is
NH
2
B.
The broad absorption band at
∼
3400–3300 cm
-
1
is due to an O
¬
H bond. The doublet at 0.9 ppm
indicates an isopropyl group. Subtracting NH
2
and (CH
3
)
2
CH from the molecular formula leaves
C
2
H
4
. Therefore, this compound is
OH