N
X
C
Hal
O
N
S
P Si
Natural
Products
Solvents
C
C
C
C C
C
349
7.11 Carbonyl Compounds
349
Examples (v ~ in cm -1 )
CH 3 –CHO
1748
O
H
1725
Cl
O
H
1742
CCl 3 –CHO
1760
O
H
1687
CHO
1700
CH O
O H
1670
CH O
N
1696
CH O
NO 2
in CCl 4 :
1717
in CHCl 3 :
1710
7.11.2 Ketones
Typical Ranges (v ~ in cm -1 )
Assignment
Range
Comments
C=O st
1775–1650
Strong; in Raman, weak to medium
Subranges:
≈1715
Aliphatic, branching at α position causes shift to
lower wavenumbers:
O
≈1695
O
≈1685
C=O st
%T
400
800
1200
1600
2000
2800
3600
X
C
Hal
O
N
S
P Si
Natural
Products
Solvents
C
C
C
C C
C
349
7.11 Carbonyl Compounds
349
Examples (v ~ in cm -1 )
CH 3 –CHO
1748
O
H
1725
Cl
O
H
1742
CCl 3 –CHO
1760
O
H
1687
CHO
1700
CH O
O H
1670
CH O
N
1696
CH O
NO 2
in CCl 4 :
1717
in CHCl 3 :
1710
7.11.2 Ketones
Typical Ranges (v ~ in cm -1 )
Assignment
Range
Comments
C=O st
1775–1650
Strong; in Raman, weak to medium
Subranges:
≈1715
Aliphatic, branching at α position causes shift to
lower wavenumbers:
O
≈1695
O
≈1685
C=O st
%T
400
800
1200
1600
2000
2800
3600