NMR Chemical Shifts of Impurities Charts


These tables can support you in identifying and separating NMR signals of impurities that might originate from residual solvents or from your reaction apparatus. Here we present the NMR shifts of the most commonly used solvents and impurities in organic synthesis measured in the 7 most frequently used deuterated solvents. Please note that the values given in the tables are temperature- and partly concentration-dependent and therefore represent average values only. The 1H-NMR data were obtained using a 300 MHz spectrometer, the 13C-NMR data using 75 MHz.

 

1H NMR Chemical Impurity Shifts Table

 

 proton  

 mult  

 CDCl3  

 (CD3)2CO

 (CD3)2SO

  C6D6  

 CD3CN 

  CD3OD  

 D2O 

Solvent residual peak

N/A

N/A

7.26

2.05

2.50

7.16

1.94

3.31

4.79

H2O

N/A

s

1.56

2.84

3.33

0.40

2.13

4.87

N/A

Acetic acid

CH3

s

2.10

1.96

1.91

1.55

1.96

1.99

2.08

Acetone

CH3

s

2.17

2.09

2.09

1.55

2.08

2.15

2.22

Acetonitrile

CH3

s

2.10

2.05

2.07

1.55

1.96

2.03

2.06

Benzene

CH

s

7.36

7.36

7.37

7.15

7.37

7.33

N/A

Tert-butyl alcohol

CH3
OH

s
s

1.28

1.18

1.11
4.19

1.05
1.55

1.16
2.18

1.40

1.24

 

 proton  

 mult  

 CDCl3  

 (CD3)2CO

 (CD3)2SO

  C6D6  

 CD3CN 

  CD3OD  

 D2O 

Tert-butyl methylether

CCH3
OCH3

s
s

1.19
3.22

1.13
3.13

1.11
3.08

1.07
3.04

1.14
3.13

1.15
3.20

1.21
3.22

BHT *a

ArH
OH
ArCH3
ArC(CH3)3

s
s
s
s

6.98
5.01
2.27
1.43

6.96

2.22
1.41

6.87
6.65
2.18
1.36

7.05
4.79
2.24
1.38

6.97
5.20
2.22
1.39

6.92

2.21
1.40

 

Chloroform

CH

s

7.26

8.02

8.32

6.15

7.58

7.90

 

Cyclohexane

CH2

s

1.43

1.43

1.40

1.40

1.44

1.45

 

 

 proton  

 mult  

 CDCl3  

 (CD3)2CO

 (CD3)2SO

  C6D6  

 CD3CN 

  CD3OD  

 D2O 

1,2-dichloroethane

CH2

s

3.73

3.87

3.90

2.90

3.81

3.78

 

Dichloromethane

CH2

s

5.30

5.63

5.76

4.27

5.44

5.49

 

Diethyl ether

CH3
CH2

t, 7
q, 7

1.21
3.48

1.11
3.41

1.09
3.38

1.11
3.26

1.12
3.42

1.18
3.49

1.17
3.56

Diglyme

CH2
CH2
OCH3

m
m
s

3.65
3.57
3.39

3.56
3.47
3.28

3.51
3.38
3.24

3.46
3.34
3.11

3.53
3.45
3.29

3.61
3.58
3.35

3.67
3.61
3.37

 

 proton  

 mult  

 CDCl3  

 (CD3)2CO

 (CD3)2SO

  C6D6  

 CD3CN 

  CD3OD  

 D2O 

1,2-dimethoxyethane

CH3
CH2

s
s

3.40
3.55

3.28
3.46

3.24
3.43

3.12
3.33

3.28
3.45

3.35
3.52

3.37
3.60

Dimethyl acetamide

CH3CO
NCH3
NCH3

s
s
s

2.09
3.02
2.94

1.97
3.00
2.83

1.96
2.94
2.78

1.60
2.57
2.05

1.97
2.96
2.83

2.07
3.31
2.92

2.08
3.06
2.90

Dimethyl formamide

CH
CH3
CH3

s
s
s

8.02
2.96
2.88

7.96
2.94
2.78

7.95
2.89
2.73

7.63
2.36
1.86

7.92
2.89
2.77

7.97
2.99
2.86

7.92
3.01
2.85

Dimethyl sulfoxide

CH3

s

2.62

2.52

2.54

1.68

2.50

2.65

2.71

Dioxane

CH2

s

3.71

3.59

3.57

3.35

3.60

3.66

3.75

 

 proton  

 mult  

 CDCl3  

 (CD3)2CO

 (CD3)2SO

  C6D6  

 CD3CN 

  CD3OD  

 D2O 

Ethanol

CH3
CH2
OH

t, 7
q, 7
s

1.25
3.72
1.32

1.12
3.57
3.39

1.06
3.44
4.63

0.96
3.34

1.12
3.54
2.47

1.19
3.60

1.17
3.65

Ethyl acetate

CH3CO
CH2CH3
CH2CH3

s
q, 7
t, 7

2.05
4.12
1.26

1.97
4.05
1.20

1.99
4.03
1.17

1.65
3.89
0.92

1.97
4.06
1.20

2.01
4.09
1.24

2.07
4.14
1.24

Ethyl methyl ketone

CH3CO
CH2CH3
CH2CH3

s
q, 7
t, 7

2.14
2.46
1.06

2.07
2.45
0.96

2.07
2.43
0.91

1.58
1.81
0.85

2.06
2.43
0.96

2.12
2.50
1.01

2.19
3.18
1.26

 

 proton  

 mult  

 CDCl3  

 (CD3)2CO

 (CD3)2SO

  C6D6  

 CD3CN 

  CD3OD  

 D2O 

Ethylene glycol

CH

s

3.76

3.28

3.34

3.41

3.51

3.59

3.65

“Grease”

CH3
CH2

m
br s

0.86
1.26

0.87
1.29





0.92
1.36

0.86
1.27

0.88
1.29





N-hexane


CH3
CH2

t
m

0.88
1.26

0.88
1.28

0.86
1.25

0.89
1.24

0.89
1.28

0.90
1.29

 

 

 proton  

 mult  

 CDCl3  

 (CD3)2CO

 (CD3)2SO

  C6D6  

 CD3CN 

  CD3OD  

 D2O 

HMPA *b

CH3

d,
9.5

2.65

2.59

2.53

2.40

2.57

2.64

2.61

Methanol

CH3
OH

s
s

3.49
1.09

3.31
3.12

3.16
4.01

3.07

3.28
2.16

3.34

3.34

Nitromethane

CH3

s

4.33

4.43

4.42

2.94

4.31

4.34

4.40

n-pentane

CH3
CH2

t, 7
m

0.88
1.27

0.88
1.27

0.86
1.27

0.87
1.23

0.89
1.29

0.90
1.29

 

 

 proton  

 mult  

 CDCl3  

 (CD3)2CO

 (CD3)2SO

  C6D6  

 CD3CN 

  CD3OD  

 D2O 

2-propanol

CH3
CH

d, 6
sep,
6

1.22
4.04

1.10
3.90

1.04
3.78

0.95
3.67

1.09
3.87

1.50
3.92

1.17
4.02

Pyridine

CH(2)
CH(3)
CH(4)

m
m
m

8.62
7.29
7.68

8.58
7.35
7.76

8.58
7.39
7.79

8.53
6.66
6.98

8.57
7.33
7.73

8.53
7.44
7.85

8.52
7.45
7.87

Silicone grease

CH3

s

0.07

0.13

 

0.29

0.08

0.10

 

Tetrahydrofuran

CH2
CH2O

m
m

1.85
3.76

1.79
3.63

1.76
3.60

1.40
3.57

1.80
3.64

1.87
3.71

1.88
3.74

 

 proton  

 mult  

 CDCl3  

 (CD3)2CO

 (CD3)2SO

  C6D6  

 CD3CN 

  CD3OD  

 D2O 

Toluene

CH3
CH(o/p)
CH(m)

s
m
m

2.36
7.17
7.25

2.32
7.1 – 7.2
7.1 – 7.2

2.30
7.18
7.25

2.11
7.02
7.13

2.33
7.1 – 7.3
7.1 – 7.3

2.32
7.16
7.16

 

Triethylamine

CH3
CH2

t, 7
q, 7

1.03
2.53

0.96
2.45

0.93
2.43

0.96
2.40

0.96
2.45

1.05
2.58

0.99
2.57

a 2,6-Dimethyl-4-tert-butylphenol
b Hexamethylphosophoramide



13C NMR Chemical Impurity Shifts Table

 

carbon

CDCl3

(CD3)2CO

(CD3)2SO

C6D6

CD3CN

 CD3OD 

D2O

Solvent signals

 

77.16

± 0.06

29.84 ± 0.01
206.26 ± 0.13

39.52
± 0.06

128.06
±0.02

1.32 ± 0.02
118.26 ± 0.02

49.00
±0.01

Acetic acid

CO
CH3

175.99
20.81

172.31
20.51

171.93
20.95

175.82
20.37

173.21
20.73

175.11
20.56

177.21
21.03

Acetone

CO
CH3

207.07
30.92

205.87
30.60

206.31
30.56

204.43
30.14

207.43
30.91

209.67
30.67

215.94
30.89

Acetonitrile

CN
CH3

116.43
1.89

117.60
1.12

117.91
1.03

116.02
0.20

118.26
1.79

118.06
0.85

119.68
1.47

Benzene

CH

128.37

129.15

128.30

128.62

129.32

129.34

 

 

carbon

CDCl3

(CD3)2CO

(CD3)2SO

C6D6

CD3CN

 CD3OD 

D2O

Tert-butyl
alcohol

C
CH3

69.15
31.25

68.13
30.72

66.88
30.38

68.19
30.47

68.74
30.68

69.40
30.91

70.36
30.29

Tert-butyl methyl  ether

CCH3
C
CCH3

49.45
72.87
26.99

49.35
72.81
27.24

48.70
72.04
26.79

49.19
72.40
27.09

49.52
73.17
27.28

49.66
74.32
27.22

49.37
75.62
26.60

BHT

C(1)
C(2)
CH(3)
C(4)
CH3Ar
CH3C
C

151.55
135.87
125.55
128.27
21.20
30.33
34.25

152.51
138.19
129.05
126.03
21.31
31.61
35.00

151.47
139.12
127.97
124.85
20.97
31.25
34.33

152.05
136.08
128.52
125.83
21.40
31.34
34.35

152.42
138.13
129.61
126.38
21.23
31.50
35.05

152.85
139.09
129.49
126.11
21.38
31.15
35.36

 

 

carbon

CDCl3

(CD3)2CO

(CD3)2SO

C6D6

CD3CN

 CD3OD 

D2O

Chloroform

CH

77.36

79.19

79.16

77.79

79.17

79.44

 

Cyclo-hexane

CH2

26.94

27.51

26.33

27.23

27.63

27.96

 

1,2-dichloroethane

CH2

43.50

45.25

45.02

43.59

45.54

45.11

 

Dichloro-methane

CH2

53.52

54.95

54.84

53.46

55.32

54.78

 

Diethyl ether

CH3
CH2

15.20
65.91

15.78
66.12

15.12
62.05

15.46
65.94

15.63
66.32

15.46
66.88

14.77
66.42

Diglyme

CH3
CH2
CH2

59.01
70.51
71.90

58.77
71.03
72.63

57.98
69.54
71.25

58.66
70.87
72.35

58.90
70.99
72.63

59.06
71.33
72.92

58.67
70.05
71.63

 

carbon

CDCl3

(CD3)2CO

(CD3)2SO

C6D6

CD3CN

 CD3OD 

D2O

1,2-dimethoxyethane

CH3
CH2

59.08
71.84

58.45
72.47

58.01
17.07

58.68
72.21

58.89
72.47

59.06
72.72

58.67
71.49

Dimethylcetamide

CH3
CO
NCH3
NCH3

21.53
171.07
35.28
38.13

21.51
170.61
34.89
37.92

21.29
169.54
37.38
34.42

21.16
169.95
34.67
37.03

21.76
171.31
35.17
38.26

21.32
173.32
35.50
38.43

21.09
174.57
 35.03
38.76

Dimethyl formamide

CH
CH3
CH3

162.62
36.50
31.45

162.79
36.15
31.03

162.29
35.73
30.73

162.13
35.25
30.72

163.31
36.57
31.32

164.73
36.89
31.61

165.53
37.54
32.03

 

carbon

CDCl3

(CD3)2CO

(CD3)2SO

C6D6

CD3CN

 CD3OD 

D2O

Dimethyl sulfoxide

CH3

40.76

41.23

40.45

40.03

41.31

40.45

39.39

Dioxane

CH2

67.14

67.60

66.36

67.16

67.72

68.11

67.19

Ethanol

CH3
CH2

18.41
58.28

18.89
57.72

18.51
56.07

18.72
57.86

18.80
57.96

18.40
58.26

17.47
58.05

Ethyl acetate

CH3CO
CO
CH2
CH3

21.04
171.36
60.49
14.19

20.83
170.96
60.56
14.50

20.68
170.31
59.74
14.40

20.56
170.44
60.21
14.19

21.16
171.68
60.98
14.54

20.88
172.89
61.50
14.49

21.15
175.26
 62.32
13.92

Ethyl methyl ketone

CH3CO
CO
CH2CH3
CH2CH3

29.49
209.56
36.89
7.86

29.30
208.30
36.75
8.03

29.26
208.72
35.83
7.61

28.56
206.55
36.36
7.91

29.60
209.88
37.09
8.14

29.39
212.16
37.34
8.09

29.49
218.43
37.27
7.87

 

carbon

CDCl3

(CD3)2CO

(CD3)2SO

C6D6

CD3CN

 CD3OD 

D2O

Ethylene glycol

CH2

63.79

64.26

62.76

64.34

64.22

64.30

63.17

“Grease”

CH2

29.76

30.73

29.20

30.21

30.86

31.29

 

N-hexane

CH3
CH2(2)
CH2(3)

14.14
22.70
31.64

14.34
23.28
32.30

13.88
22.05
30.95

14.32
23.04
31.96

14.43
23.40
32.36

14.45
23.68
32.73

 

HMPA

CH3

36.87

37.04

36.42

36.88

37.10

37.00

36.46

Methanol

CH3

50.41

49.77

48.59

49.97

49.90

49.86

49.50

Nitro-methane

CH3

62.50

63.21

63.28

61.16

63.66

63.08

63.22

 

carbon

CDCl3

(CD3)2CO

(CD3)2SO

C6D6

CD3CN

 CD3OD 

D2O

N-pentane

CH3
CH2(2)
CH2(3)

14.08
22.38
34.16

14.29
22.98
34.83

13.28
21.70
33.48

14.25
22.72
34.45

14.37
23.08
34.89

14.39
23.38
35.30

 

2-propanol

CH3
CH

25.14
64.50

25.67
63.85

25.43
64.92

25.18
64.23

25.55
64.30

25.27
64.71

24.38
64.88

Pyridine

CH(2)
CH(3)
CH(4)

149.90
123.75
135.96

150.67
124.57
136.56

149.58
123.84
136.05

150.27
123.58
135.28

150.76
127.76
136.89

150.07
125.53
138.35

149.18
125.12
138.27

Silicone grease

CH3

1.04

1.40

 

1.38

 

2.10

 

 

carbon

CDCl3

(CD3)2CO

(CD3)2SO

C6D6

CD3CN

 CD3OD 

D2O

Tetrahydro-furan

CH2
CH2O

25.62
67.97

26.15
68.07

25.14
67.03

25.72
67.80

26.27
68.33

26.48
68.83

25.67
68.68

Toluene

CH3
CH(i)
CH(o)
CH(m)
CH(p)

21.46
137.89
129.07
128.26
125.33

21.46
138.48
129.76
129.03
126.12

20.99
137.35
128.88
128.18
125.29

21.10
137.91
129.33
128.56
125.68

21.50
138.90
129.94
129.23
126.28

21.50
138.85
129.91
129.20
126.29

 

Triethyl-amine

CH3
CH2

11.61.
46.25

12.49
47.07

11.74
45.74

12.35
46.77

12.38
47.10

11.09
46.96

9.07
47.19

 

carbon

CDCl3

(CD3)2CO

(CD3)2SO

C6D6

CD3CN

 CD3OD 

D2O