C8953
NMR structural analysis
seminar
Elucidenting the structure using variouse NMR techniques
Jan Novotný
176003@mail.muni.cz
May 10, 2017
Isomerisms and NMR
Functional groups (constitution) - chemical shift
Position of substituents - HMBC, NOESY/ROESY
Relative conﬁguration on double bonds or rings J-coupling,
NOESY/ROESY
Absolute conﬁguration - application of Chiral Derivatizing
Agents (CDA)
Benzothiazole Biodegradation: 1H-15N HMBC (Appl. Environ. Microbiol., 2001, 67)
Benzothiazole Biodegradation: 1H-15N HMBC (Appl. Environ. Microbiol., 2001, 67)
Determine the structure of C10H18O using
INADEQUATE exp.
Determine the structure of C10H18O using
INADEQUATE exp.
Regioselectivity in the Halogenation: 1,1-ADEQUATE (Org. Lett., 2016, 18, 19561959)
X = O X = S
Regioselectivity in the Halogenation: 1,1-ADEQUATE (Org. Lett., 2016, 18, 19561959)
(6, 5)
(4, 3)
(4, 5)
(11, 12)(15, 14)
(12, 11)(14, 15)
(12, 13)(14, 13)
(4, 4)
F2 Chemical Shift (ppm) 8.0 7.5
116
118
120
122
124
126
128
130
132
134
136
138
140
142
144
146
148
150
152
154
12, 1412, 1412, 1412, 1412, 1412, 1412, 1412, 1412, 1412, 1412, 1412, 1412, 1412, 1412, 1412, 1412, 1412, 1412, 1412, 1412, 1412, 1411, 1511, 1511, 1511, 1511, 1511, 1511, 1511, 1511, 1511, 1511, 1511, 1511, 1511, 1511, 1511, 1511, 1511, 1511, 1511, 1511, 1511, 15
44444444444444444444446666666666666666666666
3333333333333333333333
13131313131313131313131313131313131313131313
12, 1412, 1412, 1412, 1412, 1412, 1412, 1412, 1412, 1412, 1412, 1412, 1412, 1412, 1412, 1412, 1412, 1412, 1412, 1412, 1412, 1412, 14
11, 1511, 1511, 1511, 1511, 1511, 1511, 1511, 1511, 1511, 1511, 1511, 1511, 1511, 1511, 1511, 1511, 1511, 1511, 1511, 1511, 1511, 15
5555555555555555555555
4444444444444444444444
4
3
2
N
6
5
SBr
10
11
12
13
14
15
Cl
Conﬁguration on double bonds (Magn. Reson. Chem.
2008, 46, 872–877)
Describe the isomers of molecule shown bellow:
Conﬁguration on double bonds (Magn. Reson. Chem.
2008, 46, 872–877)
Describe the isomers of molecule shown bellow:
Conﬁguration on double bonds: NOESY
Conﬁguration on double bonds: NOESY
Relative stereochemistry on a ring: NOESY
Provide the complete assignment of 1
H resonances and determine
the orientation of H5 and H6.
Relative stereochemistry on a ring: NOESY
Interpretation of J-coupling
Unknown compound C6H12O6 measured in D2O
Detected JHH-couplings: (2x9.6), (2.8, 9.6), (2x9.6), (2x2.8)
4.1 4.0 3.9 3.8 3.7 3.6 3.5 3.4 3.3 3.2
Chemical Shift (ppm)
1.02.02.11.0
1 2 3 4
1D 13
C NMR spectrum contains 4 signals in the range 71-75 ppm.
Interpretation of J-coupling
JHH-couplings: (2x9.6), (2.8, 9.6), (2x9.6), (2x2.8)
HO
HO
OH
OH
OH
OH
HO
HO
OH
OH
OH
OH
OH
OH
OHHO
HO
OH
OH
OH
OHHO
HO
OH
OH
OH
OHHO
HO
OH
OH
OH
OHHO
HO
OH
OH
OH
OHHO
HO
OH
OH
OH
OHHO
HO
OH
OH
OH
OHHO
HO
OH
OH
OH
OHHO
HO
OH
OH
OH
OHHO
HO
OH
myo scyllo muco
neo allo epi
D-chira L-chira cis
Interpretation of J-coupling
JHH-couplings: (2x9.6), (2.8, 9.6), (2x9.6), (2x2.8)
HO
HO
OH
OH
OH
OH
HO
HO
OH
OH
OH
OH
OH
OH
OHHO
HO
OH
OH
OH
OHHO
HO
OH
OH
OH
OHHO
HO
OH
OH
OH
OHHO
HO
OH
OH
OH
OHHO
HO
OH
OH
OH
OHHO
HO
OH
OH
OH
OHHO
HO
OH
OH
OH
OHHO
HO
OH
OH
OH
OHHO
HO
OH
myo scyllo muco
neo allo epi
D-chira L-chira cis
HO
OH
Interpretation of J-coupling
JHH-couplings: (2x9.6), (2.8, 9.6), (2x9.6), (2x2.8)
HO
HO
OH
OH
OH
OH
HO
HO
OH
OH
OH
OH
OH
OH
OHHO
HO
OH
OH
OH
OHHO
HO
OH
OH
OH
OHHO
HO
OH
OH
OH
OHHO
HO
OH
OH
OH
OHHO
HO
OH
OH
OH
OHHO
HO
OH
OH
OH
OHHO
HO
OH
OH
OH
OHHO
HO
OH
OH
OH
OHHO
HO
OH
myo scyllo muco
neo allo epi
D-chira L-chira cis
HO
OH
H
H
H
HO
HO
trans couplings
are large: about
10 Hz
1
Interpretation of J-coupling: MYO isomer
JHH-couplings: (2x9.6), (2.8, 9.6), (2x9.6), (2x2.8)
HO
OH
H
H
H
H
HO
HO
OH
OH
H
H4
1
3
2