reference signals for 1H NMR | |||||||
---|---|---|---|---|---|---|---|
proton type | δ (ppm) | proton type | δ (ppm) | ||||
reference | alkyl protons next to a functional group |
||||||
Si(CH3)4 (TMS) | ![]() |
0.0 | C-H as part of an acetal/ketal | ![]() |
4.4 - 6.1 | ||
hydrocarbons | C-H next to alcohol/ether | ![]() |
3.3 - 4.5 | ||||
alkane protons | ![]() |
0.7 - 2.8 | C-H next to aldehyde/ketone | ![]() |
2.0 - 2.7 | ||
alkane (methyl) protons | ![]() |
0.7 - 1.3 | C-H next to amine | ![]() |
2.2 - 2.9 | ||
alkane (methylene) protons | ![]() |
1.2 - 1.6 | C-H next to azide | ![]() |
3.4 - 4.3 | ||
alkane (methine) protons | ![]() |
1.4 - 1.8 | C-H next to carboxylic acid | ![]() |
2.1 - 4.2 | ||
aralkyl (benzylic) protons | ![]() |
2.2 - 2.8 | C-H next to carboxylic acid halide | ![]() |
2.6 - 4.1 | ||
alkene (allylic) protons | ![]() |
1.5 - 2.6 | C-H next to cyanate | ![]() |
3.6 - 4.5 | ||
alkene (vinylic) protons | ![]() |
4.5 - 6.5 | C-H next to epoxide | ![]() |
2.5 - 3.6 | ||
alkyne (acetylenic) protons | ![]() |
1.8 - 3.1 | C-H next to ester (carbonyl side) | ![]() |
2.0 - 2.2 | ||
arene (phenyl) protons | ![]() |
6.0 - 8.5 | C-H next to ester (ether side) | ![]() |
3.7 - 4.1 | ||
protons that are part of a functional group |
C-H next to halide | ![]() |
2.5 - 4.5 | ||||
alcohol (alkyl alcohol) proton | ![]() |
2.5 - 5 | C-H next to bromine | ![]() |
2.7 - 4.1 | ||
alcohol (aryl alcohol/phenolic) proton | ![]() |
5 - 8 | C-H next to chlorine | ![]() |
3.1 - 4.1 | ||
aldehyde proton | ![]() |
9.5 - 10.5 | C-H next to fluorine | ![]() |
4.0 - 4.5 | ||
amine proton | ![]() |
1 - 3 | C-H next to iodine | ![]() |
2.0 - 4.0 | ||
carboxylic acid proton | ![]() |
10 - 13 | C-H next to nitrile (cyanide) | ![]() |
2.0 - 3.6 | ||
C-H next to nitro | ![]() |
4.0 - 4.5 | |||||
C-H next to sulfone | ![]() |
2.5 - 3.5 | |||||
C-H next to thioalcohol/thioether | ![]() |
2.0 - 4.0 |
splitting patterns in 1H NMR | ||
---|---|---|
number of equivalent couplings |
multiplet appearance |
integral ratio |
0 | singlet (s) | 1 |
1 | doublet (d) | 1 : 1 |
2 | triplet (t) | 1 : 2 : 1 |
3 | quartet (q) | 1 : 3 : 3 : 1 |
4 | quintet | 1 : 4 : 6 : 4 : 1 |
5 | sextet | 1 : 5 : 10 : 10 : 5 : 1 |
6 | septet | 1 : 6 : 15 : 20 : 15 : 6 : 1 |
3JHH coupling constants in 1H NMR | |||||
---|---|---|---|---|---|
cis-alkene | 4 - 12 Hz | cis-cycloalkane (Jax,eq) | 4 - 5 Hz | ||
trans-alkene | 12 - 18 Hz | trans-cycloalkane (Jax,ax) | 10 - 14 Hz |
reference signals for 13C NMR | |||||||
---|---|---|---|---|---|---|---|
carbon type | δ (ppm) | carbon type | δ (ppm) | ||||
hydrocarbons | next to a functional group | ||||||
methyl | ![]() |
0 - 35 | C next to alcohol | ![]() |
50 - 65 | ||
methylene | ![]() |
15 - 40 | C next to amine | ![]() |
35 - 50 | ||
methine | ![]() |
25 - 50 | C next to azide | ![]() |
10 - 60 | ||
quaternary carbon | ![]() |
30 - 40 | C next to bromine | ![]() |
20 - 40 | ||
alkene | ![]() |
100 - 150 | C next to chlorine | ![]() |
25 - 50 | ||
alkyne | ![]() |
65 - 90 | C next to ether | ![]() |
50 - 75 | ||
arene | ![]() |
110 - 175 | C next to fluorine | ![]() |
80 - 95 | ||
in a functional group | C next to iodine | ![]() |
0 - 20 | ||||
C in an aldehyde/ketone | ![]() |
190 - 220 | C next to a nitro | ![]() |
65 - 80 | ||
C in an amide | ![]() |
150 - 180 | C next to thioether | ![]() |
20 - 45 | ||
C in a carboxylic acid or ester | ![]() |
160 - 185 | |||||
C in a cyanate | ![]() |
120 - 130 | |||||
C in a nitrile (cyanide) | ![]() |
110 - 125 |