N
X
C
O
N
S
Hal
Solvents
Natural
Products
P Si
C
C
C C
C
C
178
5 1 H NMR
Estimation of 1 H Chemical Shifts of Substituted Ethylenes (δ in ppm)
δ C=CH = 5.25 + Z gem + Z cis + Z trans
Substituent R
Z gem
Z cis
Z trans
–H
0.00
0.00
0.00
–alkyl
0.45
-0.22
-0.28
–alkyl ring 1
0.69
-0.25
-0.28
–CH 2 –aromatic
1.05
-0.29
-0.32
–CH 2 X, X: F, Cl, Br
0.70
0.11
-0.04
–CHF 2
0.66
0.32
0.21
–CF 3
0.66
0.61
0.32
–CH 2 O–
0.64
-0.01
-0.02
–CH 2 N
0.58
-0.10
-0.08
–CH 2 CN
0.69
-0.08
-0.06
–CH 2 S–
0.71
-0.13
-0.22
–CH 2 CO–
0.69
-0.08
-0.06
–C=C
1.00
-0.09
-0.23
–C=C conjugated 2
1.24
0.02
-0.05
–C– – – C–
0.47
0.38
0.12
–aromatic
1.38
0.36
-0.07
–aromatic, fixed 3
1.60
–
-0.05
–aromatic, o-substituted
1.65
0.19
0.09
–F
1.54
-0.40
-1.02
–Cl
1.08
0.18
0.13
–Br
1.07
0.45
0.55
–I
1.14
0.81
0.88
–OC (sp 3 )
1.22
-1.07
-1.21
–OC= (sp 2 )
1.21
-0.60
-1.00
–OCO–
2.11
-0.35
-0.64
–OP(O)(OCH 2 CH 3 ) 2
1.33
-0.34
-0.66
–NR 2 ; R: H, C (sp 3 )
0.80
-1.26
-1.21
–NR–; R: C= (sp 2 )
1.17
-0.53
-0.99
–NCO–R
2.08
-0.57
-0.72
–N=N–phenyl
2.39
1.11
0.67
–NO 2
1.87
1.30
0.62
–C– – – N
0.27
0.75
0.55
H
R gem
R trans
R cis
C
X
O
N