♦ Tension C=O: 1725 cm -1

♦ CH carbonyl strain: two weak bands at 2850 and 2750 cm -1 . The band at 2850 tends to overlap with that of tension C(sp 3 )-H

♦ C=O Voltage Overtone over 3500 cm -1 .

IR spectrum of cyclohexanecarbaldehyde


Observe how the CH (carbonyl) tension band at 2850 overlaps with the C(sp 3 )-H tension band

IR spectrum of Benzaldehyde

In this spectrum, the tension bands of the CH carbonyl bond can be more clearly observed. In addition, the absorption bands of benzene are indicated.


Identify bands in the spectrum of acetaldehyde