Transcript Spectroscopy of Aldehydes and Ketones IR Spectrum of Acetone C=O IR Spectrum of Acetophenone C=O.

Spectroscopy of
Aldehydes and Ketones
IR Spectrum of Acetone
C=O
IR Spectrum of Acetophenone
C=O
IR Spectrum of Acetaldehyde
Ald. C-H
C=O
IR Spectrum of p-Tolualdehyde
Ald.C-H
C-H
Ald.
C=O
C=O
O
CH3CCH3
CH3
O
C
CDCl3 (solvent)
H
C
H
O
C
C
C
C
C
C
and
C
H
H
CH3
C
H
CDCl3 (solvent)
C
C
H
H
O
CH3C
H
H
H
O
H C
CH3
O
CH3CCH3
H
CH3
H
O
H
H
CH3C
H
H
H
H
CH3
H
C
H
H
H
C
C
C
H
H
C
C
H
H
O
H C
CH3
Summary of Spectral Features
IR:
13C-NMR:
1H-NMR:
1710-1730 cm-1 (C=O stretching frequency)
(lower by ~ 20 to 30 cm-1 if C=O is conjugated)
aldehydes only: C-H stretch: 2820 & 2720 cm-1
both aldehydes and ketones have a
characteristic C=O peak at 190-215 d.
aldehydes only: ald. C-H absorbs at 10 d.
both aldehydes and ketones have Hs a to
C=O at 2.2-2.5 d.