Increment system for estimation of chemical shifts of alkane protons
Formula:
| Substituent | Increment | Comment |
| -alkyl | 0 | |
| -C=C- | 0.8 | alkene |
| -CC- | 0.9 | alkyne |
| -C6H5 | 1.3 | phenyl |
| CHO, CO-alkyl | 1.2 | |
| -CO-C6H5 | 1.6 | |
| -COOH | 0.8 | acid |
| -COO-alkyl | 0.7 | ester |
| -CN | 1.2 | nitrile |
| -NH2, NH-alkyl, N(alkyl)2 | 1.0 | amine |
| -NO2 | 3.0 | |
| -SH, S-alkyl | 1.3 | |
| -OH | 1.7 | phenol |
| -O-alkyl | 1.5 | ether |
| -O-C6H5 | 2.3 | |
| -O-CO-alkyl | 2.7 | |
| -O-CO-C6H5 | 2.9 | |
| -Cl | 2.0 | |
| -Br | 1.9 | |
| -I | 1.4 | |
Example: Chloro acetic acid ethyl ester
