2 DIMENSIONAL NMR ORGANIC SPECTROSCOPY by DR ANTHONY CRASTO

1. 2 D N M R
O R G A N I C
S P E C T R O S C O P Y
DR ANTHONY MELVIN CRASTO
PRESENTS

2. HELLO!
I AM DR ANTHONY
MELVIN CRASTO
WORLDDRUGTRACKER
HELPING MILLIONS

3. Agenda
1 2D NMR Basics.
2 2D COSY
3 HETCOR
4 TOCSY
5 DEPT
6 NOESY
7 ROESY

4. Two-dimensional nuclear magnetic resonance
spectroscopy (2D NMR)
• Two-dimensional nuclear magnetic resonance spectroscopy (2D NMR) is a set of
nuclear magnetic resonance spectroscopy (NMR) methods which give data plotted in a
space defined by two frequency axes rather than one. Types of 2D NMR include
correlation spectroscopy (COSY), J-spectroscopy, exchange spectroscopy
(EXSY), and nuclear Overhauser effect spectroscopy (NOESY). Two-dimensional
NMR spectra provide more information about a molecule than one-dimensional NMR
spectra and are especially useful in determining the structure of a molecule,
particularly for molecules that are too complicated to work with using one-dimensional
NMR.
• The first two-dimensional experiment, COSY, was proposed by Jean Jeener, a
professor at the Université Libre de Bruxelles, in 1971. This experiment was later
implemented by Walter P. Aue, Enrico Bartholdi and Richard R. Ernst, who published
their work in 1976

5. Structure Determination Procedures
1D 1H & 13C & DEPT (+MS 、 IR ， basic chemical structure or
functional groups information）
Establish 13C-1H connections by thru bond JCH couplings
HMQC、HSQC、HSQC-TOCSY experiments
Establish 1H-1H connection (spin systems or partial pieces）
Decoupled 1H, 1D TOCSY, 2D 1H-1H COSY, TOCSY expts.
（usually starts with well-resolved 1H signals）
Long range connections （ connecting spin systems & assigning
quaternary carbon）
1D NOESY & 2D HMBC, NOESY, ROESY experiments
3D structure or conformation determination
1D NOESY & 2D NOESY, ROESY, (HSQC)-NOESY expts.

6. MY BLOGS
ORGANIC SPECTROSCOPY INTERNATIONAL
LINK….. http://orgspectroscopyint.blogspot.in/
ORGANIC SPECTROSCOPY INTERNATIONAL
Organic Chemists from Industry and academics to Interact on
Spectroscopy Techniques for Organic Compounds ie NMR, MASS,
IR, UV Etc. Starters, Learners, advanced, all alike, contains content
which is basic or advanced, by Dr Anthony Melvin Crasto,
Worlddrugtracker, email me ........... amcrasto@gmail.com, call +91
9323115463

7. LIONEL MY SON
He was only in first standard in school when I was hit by a
deadly one in a million spine stroke called acute transverse
mylitis, it made me 90% paralysed and bound to a wheel
chair,
Now I keep him as my source of inspiration and helping
millions, thanks to millions of my readers who keep me
going and help me to keep my son happy

8. 2D NMR BASICS1

9. PROTON-PROTON CORRELATION THROUGH J-
COUPLING
2D NMR Basics.
• In actuality, the techniques we have already covered 1H, 13C, and DEPT are 2-D (frequency vs.
intensity) however, by tradition the intensity component is dropped when discussing
dimensionality
• In 2-D techniques, many FIDs (proto-NMR spectra) are taken one after another, with some
acquisition variable or pulse sequenced varied by small increments
• Since each FID is a collection of digitized data points in the first dimension (say 10 points to
make a spectrum) if 10 spectra are accumulated with an incremental change in variable, an FT
can be performed in the other dimension
. . . . . . . . . .
. . . . . . . . . .
. . . . . . . . . .
. . . . . . . . . .
. . . . . . . . . .
. . . . . . . . . .
. . . . . . . . . .
. . . . . . . . . .
. . . . . . . . . .
. . . . . . . . . .
. . . . . . . . . .
. . . . . . . . . .
. . . . . . . . . .
. . . . . . . . . .
. . . . . . . . . .
. . . . . . . . . .
. . . . . . . . . .
. . . . . . . . . .
. . . . . . . . . .
. . . . . . . . . .
1-D FID
1-D spectra, each
with an incremental
variable change
FTs can be performed on
the vertical data sets

10. PROTON-PROTON CORRELATION THROUGH J-
COUPLING
2D NMR Basics.
• The first perturbation of the system (pulse) is called the preparation of the spin system.
• The effects of this pulse are allowed to coalesce; this is known as the evolution time, t1 (NOT T1
– the relaxation time)
• During this time, a mixing event, in which information from one part of the spin system is
relayed to other parts, occurs
• Finally, an acquisition period (t2) as with all 1-D experiments.
Preparation Evolution Acquisition
t1 t2
Mixing

11. NMR
spectrum
Structure
Chem. Shift
J Coupling
Peak Int.
NOE
Correlation
H-H，C-H
O
O
OH
O
CH3
O
H
OH
OH
OH
CH2OH
COOCH2
1
2
3
4
5
6
7
8
9
10
1''
2''3''
4''
5'' 6''
1'
2'3'
4'
5'
6'
7''
Applications:
• Sample quality control for Synthetic works.
• Elucidation of chemical structures.
• Getting functional group, bonding, dynamics, kinetics and chemical exchange information of molecules.
• 3D structures of the molecules.
NMR Applications in Chemistry

12.  Connections through space（dipolar coupling）
1D、2D NOESY，ROESY, HOESY(HSQC-NOESY)
usage： connecting spin systems 、structure determination
 Connections through bonds（spin-spin coupling）
Homonuclear： 1D、2D 1H-1H COSY, DQF-COSY, TOCSY
usage：spin system assignment
Heteronuclear：
Direct (detect 13C): APT, DEPT, HETCOR
Inverse (detect1H): HMQC, HSQC, HMBC, HSQC-COSY,
HSQC-TOCSY, HMQC-TOCSY
usage：assigning heteronuclei、connecting spin systems
Some common NMR experiments:

13. COSY spectrum is used for determining the connectivities
between protons on the basis of geminal and vicinal couplings.
Disadvantage: bulky dispersive diagonal peaks.
C C H
HH
Vicinal
Geminal
2D COSY — Homonuclear Shift COrrelation SpectroscopY
t1 AQ
The basic COSY (x=45° or 90°) pulse sequence
90° x°
t2

14. ppm
1.01.52.02.53.03.5 ppm
1.0
1.5
2.0
2.5
3.0
3.5
Current Data Parameters
NAME butcosy
EXPNO 1
PROCNO 1
F2 - Acquisition Parameters
Date_ 20001102
Time 8.04
INSTRUM DRX500
PROBHD 5 mm TBI 1H/
PULPROG cosygp
TD 1024
SOLVENT CDCl3
NS 1
DS 16
SWH 2185.315 Hz
FIDRES 2.134096 Hz
AQ 0.2345700 sec
RG 40.3
DW 228.800 usec
DE 6.00 usec
TE 288.0 K
D0 0.00000300 sec
D1 1.60000002 sec
D13 0.00000300 sec
D16 0.00010000 sec
IN0 0.00045765 sec
============ CHANNEL f1 =============
NUC1 1H
P0 3.00 usec
P1 6.00 usec
PL1 -4.00 dB
SFO1 500.1310815 MHz
============ GRADIENT CHANNEL ========
GPNAM1 sine.100
GPNAM2 sine.100
GPX1 0.00 %
GPX2 0.00 %
GPY1 0.00 %
GPY2 0.00 %
GPZ1 10.00 %
GPZ2 10.00 %
P16 1000.00 usec
F1 - Acquisition parameters
ND0 1
TD 256
SFO1 500.1311 MHz
FIDRES 8.535453 Hz
SW 4.369 ppm
FnMODE undefined
F2 - Processing parameters
SI 2048
SF 500.1300144 MHz
WDW QSINE
SSB 0
LB 0.00 Hz
GB 0
PC 0.20
F1 - Processing parameters
SI 1024
MC2 QF
SF 500.1300144 MHz
WDW QSINE
SSB 0
LB 0.00 Hz
GB 0
1 2 3 41
234
HO C
H1
H
C C C
H2
H
H3
H
H4
H
H
1-2
2-3
3-4
2D Gradient COSY-45

15. 2D COSY NMR2

16. Correlated Spectroscopy

17. FT of the t1 domain, acetone

18. October 20, 2004 Joanna R. Long 15
2D Exchange NMR
A. S. Edison
University of Florida
t1 t2






FT of t2
FTint1willgive2Dfrequencyspectrum

19. PROTON-PROTON CORRELATION THROUGH J-
COUPLING
2D COSY.
• H-H COrrelation SpectroscopY (COSY):
• The pulse sequence for COSY is as follows:
• A 90o pulse in the x-direction is what we used for 1-D 1H NMR
• Here, after a variable “mixing” period, a second 90o pulse is performed, followed by
acquisition of a spectrum
19
90x90x
t1
t2

20. October 20, 2004 Joanna R. Long 16
15 l N•Ndimethylacetamide in 700 l d-chloroform at 29° C

21. A-B coupling in COSY Spectrum

22. CH3CH2CCH3
O

23. CH2CH3

24. Isobutyl Alcohol
OH

25. O
O

26. 1H NMR Spectrum of Ipsenol

27. COSY Spectra of Ipsenol

28. Share a big idea or quote here.

29. HETCOR3

30. Heteronuclear through-bond correlation methods
• Heteronuclear correlation spectroscopy gives signal based upon coupling between
nuclei between two different types. Often the two nuclei are protons and another
nucleus (called a "heteronucleus"). For historical reasons, experiments which record
the proton rather than the heteronucleus spectrum during the detection period are
called "inverse" experiments.
• This is because the low natural abundance of most heteronuclei would result in the
proton spectrum being overwhelmed with signals from molecules with no active
heteronuclei, making it useless for observing the desired, coupled signals.
• With the advent of techniques for suppressing these undesired signals, inverse
correlation experiments such as HSQC, HMQC, and HMBC are actually much more
common today. "Normal" heteronuclear correlation spectroscopy, in which the
hetronucleus spectrum is recorded, is known as HETCOR

31. Heteronuclear multiple-bond correlation
spectroscopy (HMBC)
• HMBC detects heteronuclear correlations over longer ranges of about 2–4 bonds. The
difficulty of detecting multiple-bond correlations is that the HSQC and HMQC
sequences contain a specific delay time between pulses which allows detection only of
a range around a specific coupling constant. This is not a problem for the single-bond
methods since the coupling constants tend to lie in a narrow range, but multiple-bond
coupling constants cover a much wider range and cannot all be captured in a single
HSQC or HMQC experiment.
• In HMBC, this difficulty is overcome by omitting one of these delays from an HMQC
sequence. This increases the range of coupling constants that can be detected, and
also reduces signal loss from relaxation. The cost is that this eliminates the possibility
of decoupling the spectrum, and introduces phase distortions into the signal. There is a
modification of the HMBC method which suppresses one-bond signals, leaving only
the multiple-bond signals

32. Heteronuclear single-quantum correlation
spectroscopy (HSQC)
• HSQC detects correlations between nuclei of two different types which are separated
by one bond. This method gives one peak per pair of coupled nuclei, whose two
coordinates are the chemical shifts of the two coupled atoms.
• HSQC works by transferring magnetization from the I nucleus (usually the proton) to
the S nucleus (usually the heteroatom) using the INEPT pulse sequence; this first step
is done because the proton has a greater equilibrium magnetization and thus this step
creates a stronger signal. The magnetization then evolves and then is transferred back
to the I nucleus for observation. An extra spin echo step can then optionally be used to
decouple the signal, simplifying the spectrum by collapsing multiplets to a single peak.
The undesired uncoupled signals are removed by running the experiment twice with
the phase of one specific pulse reversed; this reverses the signs of the desired but not
the undesired peaks, so subtracting the two spectra will give only the desired
peaks.Heteronuclear multiple-quantum correlation spectroscopy (HMQC) gives an
identical spectrum as HSQC, but using a different method. The two methods give
similar quality results for small to medium-sized molecules, but HSQC is considered to
be superior for larger molecules

33. HETCOR (Heteronuclear chemical shift correlation, 1H - 13C COSY)
13C
1H t1 1 2
The standard pulse sequence for 13C-detected
1H-13C chemical shift correlation.
AQ
t2
1H decoupling
Removing JCH splittings
*But Inverse experiment has the following Advantages:
•increase sensitivity of detecting the less sensitive nuclei
•1H is in the direct detection dimension => larger np => better
resolution

34. HMBC (Heteronuclear Multiple-Bond Correlation Spectroscopy)
13C
1H t1 AQ
C2, C3 and C4: Quaternary or protonated carbons X: O, N
C1 C2 C3 C4
H1
C1 X C2 C3
H1
Pulse sequence for HMBC
Long range connections or connections between spin systems

35. HETCOR Spctrum of Ipsenol

36. N
COCH2CH3
O
H
H
H
H
Exercise 5.6, p. 291

37. N
COCH2CH3
O
H
H
H
H
Exercise 5.6, p. 292

38. O
CH3

39. ppm
1.01.52.02.53.03.5 ppm
10
15
20
25
30
35
40
45
50
55
60
65
Current Data Parameters
NAME buthsqc
EXPNO 1
PROCNO 1
F2 - Acquisition Parameters
Date_ 20001102
Time 10.31
INSTRUM DRX500
PROBHD 5 mm TBI 1H/
PULPROG invietgpsi
TD 1024
SOLVENT CDCl3
NS 1
DS 16
SWH 2185.315 Hz
FIDRES 2.134096 Hz
AQ 0.2345700 sec
RG 2298.8
DW 228.800 usec
DE 6.00 usec
TE 300.0 K
D0 0.00000300 sec
D1 2.00000000 sec
D4 0.00170000 sec
D11 0.03000000 sec
D13 0.00000300 sec
D16 0.00010000 sec
D24 0.00090000 sec
DELTA 0.00116720 sec
DELTA1 0.00110700 sec
IN0 0.00003600 sec
l3 256
============ CHANNEL f1 =============
NUC1 1H
P1 5.60 usec
P2 11.20 usec
P28 2500.00 usec
PL1 -4.00 dB
SFO1 500.1310815 MHz
============ CHANNEL f2 =============
CPDPRG2 garp
NUC2 13C
P3 17.70 usec
P4 35.40 usec
PCPD2 89.00 usec
PL2 -1.00 dB
PL12 13.00 dB
SFO2 125.7633722 MHz
============ GRADIENT CHANNEL ========
GPNAM1 sine.100
GPNAM2 sine.100
GPX1 0.00 %
GPX2 0.00 %
GPY1 0.00 %
GPY2 0.00 %
GPZ1 80.00 %
GPZ2 20.10 %
P16 1000.00 usec
F1 - Acquisition parameters
ND0 2
TD 512
SFO1 125.7634 MHz
FIDRES 27.126736 Hz
SW 110.437 ppm
FnMODE undefined
F2 - Processing parameters
SI 1024
SF 500.1300144 MHz
WDW SINE
SSB 2
LB 0.00 Hz
GB 0
PC 0.20
F1 - Processing parameters
SI 1024
MC2 echo-antiecho
SF 125.7577969 MHz
WDW SINE
SSB 2
LB 0.00 Hz
GB 0
HO C
H1
H
C C C
H2
H
H3
H
H4
H
H
1 2 3 4
1234
HSQC spectrum: H-C correlatedC-
dimensio
n
H-dimension

40. TOCSY4

41. Total correlation spectroscopy (TOCSY)
• The TOCSY experiment is similar to the COSY experiment, in that cross peaks of
coupled protons are observed. However, cross peaks are observed not only for nuclei
which are directly coupled, but also between nuclei which are connected by a chain of
couplings. This makes it useful for identifying the larger interconnected networks of
spin couplings. This ability is achieved by inserting a repetitive series of pulses which
cause isotropic mixing during the mixing period. Longer isotropic mixing times cause
the polarization to spread out through an increasing number of bonds.
• In the case of oligosaccharides, each sugar residue is an isolated spin system, so it is
possible to differentiate all the protons of a specific sugar residue. A 1D version of
TOCSY is also available and by irradiating a single proton the rest of the spin system
can be revealed. Recent advances in this technique include the 1D-CSSF-TOCSY
(Chemical Shift Selective Filter - TOCSY) experiment, which produces higher quality
spectra and allows coupling constants to be reliably extracted and used to help
determine stereochemistry.
• TOCSY is sometimes called "homonuclear Hartmann–Hahn spectroscopy" (HOHAHA)

43. A

44. TOCSY (TOtal Correlation SpectroscopY) or
HOHAHA(Homonuclear Hartman-Hahn Spectroscopy)
t1  MLEV17 AQ
Pulse sequence for a TOCSY spectrum.
Different mixing time gives different degree of relay of correlation.
At small mixing time, TOCSY spectrum is similar to COSY
spectrum. At long mixing time, gives total correlation.
HO C
H1
H
C C C
H2
H
H3
H
H4
H
H
HO C
H1
H
C C C
H2
H
H3
H
H4
H
H
HO C
H1
H
C C C
H2
H
H3
H
H4
H
HCOSY RL-COSY TOCSY
mixing time t2

45. DEPT5

46. DEPT-90, DEPT-135
Distortionless Enhancement by Polarization
Transfer
• Preferred procedure for determining #
protons attached to carbons
• Variable proton pulse angle q is set at 90o
and 135o
• In DEPT-90, only CH shows. In DEPT-135,
CH2’s are phased down, CH and CH3 are
phased up

47. DEPT: Distortionless Enhancement by Polarization Transfer
Heteronuclear expt.
Detection: 13C
Distinguish
CH, CH2, CH3
By suitable combination of
q=45, 90 & 135 spectra
All CH’s
Only CH
CH & CH3up
CH2 down

48. Adjustment of 1H pulse angle
Avoids overlapping multiplets
CH
CH2
CH3

49. 2-Heptanone, CPD and DEPT-35

50. 6-Methyl-5-hepten-2-ol
Standard CPD Spectrum

51. DEPT-90
DEPT-135
OH

52. O
CH3
DEPT-135
DEPT-90

54. <
>

55. Ipsenol
CPD, DEPT-135, DEPT 90
7
6
2
5 3
4 1
9
8,10

56. 2D NOESY6

57. Nuclear Overhauser effect spectroscopy
(NOESY)In NOESY, the Nuclear Overhauser cross relaxation between nuclear spins during the mixing
period is used to establish the correlations. The spectrum obtained is similar to COSY, with
diagonal peaks and cross peaks, however the cross peaks connect resonances from nuclei that
are spatially close rather than those that are through-bond coupled to each other. NOESY
spectra also contain extra axial peaks which do not provide extra information and can be
eliminated through a different experiment by reversing the phase of the first pulse.
One application of NOESY is in the study of large biomolecules such as in protein NMR, which
can often be assigned using sequential walking.
The NOESY experiment can also be performed in a one-dimensional fashion by pre-selecting
individual resonances. The spectra are read with the pre-selected nuclei giving a large, negative
signal while neighboring nuclei are identified by weaker, positive signals. This only reveals which
peaks have measurable NOEs to the resonance of interest but takes much less time than the full
2D experiment. In addition, if a pre-selected nucleus changes environment within the time scale
of the experiment, multiple negative signals may be observed. This offers exchange information
similar to the EXSY (exchange spectroscopy) NMR method.
NOESY experiment is important tool to identify stereochemistry of a molecule in solvent whereas
single crystal XRD used to identify stereochemistry of a molecule in solid form.

58. 2D NOESY (Nuclear Overhauser Enhancements SpectroscopY)
t1 m AQ
The NOESY pulse sequence.
—C — ~ —C —
Ha Hb VC*r -6, r0.5nm
r0.5nm
For resonance assignment, chemical structure elucidation &
3D structure determination
t2

59. ppm
3.54.04.55.05.56.06.57.07.5 ppm
3.5
4.0
4.5
5.0
5.5
6.0
6.5
7.0
7.5
8.0
Current Data Parameters
NAME cfynoesy
EXPNO 1
PROCNO 1
F2 - Acquisition Parameters
Date_ 20001103
Time 8.53
INSTRUM DRX500
PROBHD 5 mm TBI 1H/
PULPROG noesygptp
TD 1024
SOLVENT CDCl3
NS 8
DS 16
SWH 3443.526 Hz
FIDRES 3.362818 Hz
AQ 0.1488800 sec
RG 64
DW 145.200 usec
DE 6.00 usec
TE 288.0 K
D0 0.00000300 sec
D1 1.60000002 sec
D8 0.40000001 sec
D16 0.00010000 sec
d20 0.19890000 sec
IN0 0.00014520 sec
============ CHANNEL f1 =============
NUC1 1H
P1 6.00 usec
P2 12.00 usec
PL1 -4.00 dB
SFO1 500.1326379 MHz
============ GRADIENT CHANNEL ========
GPNAM1 sine.100
GPNAM2 sine.100
GPX1 0.00 %
GPX2 0.00 %
GPY1 0.00 %
GPY2 0.00 %
GPZ1 40.00 %
GPZ2 -40.00 %
P16 1000.00 usec
F1 - Acquisition parameters
ND0 2
TD 256
SFO1 500.1326 MHz
FIDRES 13.451274 Hz
SW 6.885 ppm
FnMODE undefined
F2 - Processing parameters
SI 1024
SF 500.1300144 MHz
WDW SINE
SSB 2
LB 0.00 Hz
GB 0
PC 0.20
F1 - Processing parameters
SI 1024
MC2 TPPI
SF 500.1300144 MHz
WDW SINE
SSB 2
LB 0.00 Hz
GB 0
N
N N
N
O
O
CH3
CH3
H3C
H
1
3
5
2
8
7
6
4
3-CH3, 5-H
Gradient NOESY

60. NOESY
gives sequential
assignment of peptides
21 2 3
CH2
CH2N C
H
N
O
H
C C
H
CH2O
N
H
C
CH2
C
H
OH
O
1 321

61. 2D ROESY7

62. Rotating frame nuclear Overhauser effect
spectroscopy (ROESY)
• ROESY is similar to NOESY, except that the initial state is different. Instead of
observing cross relaxation from an initial state of z-magnetization, the equilibrium
magnetization is rotated onto the x axis and then spin-locked by an external magnetic
field so that it cannot precess. This method is useful for certain molecules whose
rotational correlation time falls in a range where the Nuclear Overhauser effect is too
weak to be detectable, usually molecules with a molecular weight around 1000 daltons,
because ROESY has a different dependence between the correlation time and the
cross-relaxation rate constant. In NOESY the cross-relaxation rate constant goes from
positive to negative as the correlation time increases, giving a range where it is near
zero, whereas in ROESY the cross-relaxation rate constant is always positive.
• ROESY is sometimes called "cross relaxation appropriate for minimolecules emulated
by locked spins" (CAMELSPIN)

63. Spin-lock
90°
t1 t2
2D ROESY pulse program
For small molecule NOE can be very small or zero，
ROESY can be used in place of NOESY experiment. ROE
intensity is also related to the H-H distances.
mixing time

64. 2D ROESY spectrum of ethylbenzene

65. Structure of 12,14-
ditbutylbenzo[g]chrysene showing color
conding of rings

66. Aromatic region of the 2D ROESY spectrum of 12,14-
ditbutylbenzo[g]chrysene showing connectivity and separation into four
color-coded proton groups

67. CASE STUDY ..ASPIRIN1

68. 1 H-NMR spectrum of acetylsalicylic acid

69. H, H-COSY spectrum of acetylsalicylic acid

70. THANK YOU!