90
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A few more
examples on the topic of couplings:
(You might also want to check page 85
for some additional explanations.)
 |
|
The protons of the methyl group don't couple,
since they are
 . |
| CH3-CO-CH2Br |
|
The protons of the methyl and the methylen groups
don't show any detectable coupling,
since they are
 . |
| BrCH2-CºC-H |
|
The methyl protons couple with the ºC-H (JH,CH2
= 2.7 Hz), although they are connected through
 bonds, since due to
the CºC triple bond the
coupling becomes
 . |
Now try your luck with these two problems:
Determin for these two molecules which proton
groups will couple with each other, and which ones won't.
(Give the reason for your answers!)
| A) |
|
B) |
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|
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Continue on page 93! |
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