Exercise plus Solution – Quick overview
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18.28
21.00
32.17
39.83
58.36
104.27
193.16
204.00
30405060708090100110120140150160170180190200
ppm
13
C
~
13
C{
1
H} NMR spectrum
measured at 62.9{250.13} MHz
1,3-Cyclohexadion measured in CDCl
3
1,3-cyclohexadione exists in equilibrium with its enol form..
- Assign the signals of both tautomers completely.
- Determine the amount of both tautomers in equilibrium.
- The integral of the proton signal at 10ppm is slightly larger
than theoretically expected. What might be the reason?
2.02.53.03.54.04.55.05.56.07.07.58.08.59.09.510.0
ppm
1
H
9.96
2.36
3.11
1.62
0.74
0.74
1.00
Inte-
gral
3.45
5.59
651.03
657.72
664.28
Hz
499.17
505.46
510.06
511.59
516.17
Hz
603.43
609.89
616.28
Hz
1
H NMR spectrum
recorded at 250.13 MHz
Please don‘t try to fully analyze the
multiplets. You might get tiny hints from
the multiplet structure.
~
20
30
40
50
60
70
90
100
13
C
2.02.53.03.54.05.05.56.0
1
H
ppm
2.02.53.03.54.05.05.56.0
1
H
ppm
20
40
60
80
100
120
160
180
200
13
C
~
1
H/
13
C HSQC
recorded at 250.13/62.9 MHz
1
H/
13
C HMBC
recorded at
250.13/62.9 MHz
O O
HH
C
C
C
H
H
C
H
H C
C
HH
O OC
C
C
H
H
C
H
H C
C
HH
HH
3.45 ppm
2.63 ppm
2.05 ppm
9.96 ppm
5.59 ppm
2.44 ppm
2.02 ppm
204.00
193.16
58.36
104.27
39.83
18.28
21.00
32.17
32 %
68 %
Solution at a glance
There is no step by step solution available so far.
