IR Spectrum Wavenumbers

1200 cm-1

1660 cm-1

isolated: 1640-1680 cm-1

conjugated: 1620-1640 cm-1

aromatic: 1600 cm-1

2200 cm-1

sp3 C-H

below 3000 cm-1

sp2 C-H

above 3000 cm-1

sp C-H

3300 cm-1

1500&1600 cm-1 C=C peak

C-H bonds off ring similar peak to vinyl C-H at 3000-3100 cm-1

R-O-R’

C-O-C stretch at 1050-1150 cm-1

R-OH

3300 cm-1 broad with rounded tip

C-O stretch between 1050-1260 cm-1

R2NH (secondary amine)

3300 cm-1 broad with one sharp spike

RNH2 (primary amine)

3300 cm-1 with 2 sharp spikes

deformation band at 1590-1650 cm-1

C=O

1720 cm-1

Aldehydes

C=O: 1720 cm-1

2 C-H signals: 2700 and 2800 cm-1

carboxylic acids

C=O: 1720 cm-1

O-H: 2500-3500 cm-1

C=O: 1735-1750 cm-1

C-O: 1150-1250 cm-1

C=O band is split in 2 with one at 1740-1770 cm-1 and the other at 1810-1840 cm-1

C-O: 1000-1100 cm-1

C=O: 1770-1820 cm-1

C=O: 1640-1680 cm-1

R2NH: 3300 cm-1

or

RNH2: 3300 cm-1 2 sharp spikes

C=N

1660 cm-1

Nitrile

above 2200 cm-1

NO2

two bands at 1300-1380 cm-1 and 1500-1570 cm-1