what nmr can do for you - university of illinois · 2019-04-02 · what nmr can do for you •...

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What NMR Can Do for You Structure Elucidation of Small Molecules Structure identification of synthetic compounds, intermediates, impurities, mixtures, unknowns, regiochemistry, rotamerization Quantitative NMR Chemical exchange: Equilibrium or A(Di)ssociation constants Reaction monitoring or reaction rates Diffusion coefficients (DOSY NMR): monomer? dimer? Enantiomeric purity determination Absolute stereochemistry determination Dynamics (T 1 , T 2 and NOE) Intramolecular hydrogen-bond determination Parahydrogen-NMR (enhance NMR signals thousands fold) to study reaction pathways NMR Screening (Protein-Ligand Interaction) Structure and Dynamics of Macromolecules and Complexes (e.g., peptides and proteins) Metabolites Analysis NMR Lab Overview by Lingyang Zhu

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Page 1: What NMR Can Do for You - University Of Illinois · 2019-04-02 · What NMR Can Do for You • Structure Elucidation of Small Molecules • Structure identification of synthetic compounds,

What NMR Can Do for You

• Structure Elucidation of Small Molecules

• Structure identification of synthetic compounds, intermediates, impurities, mixtures, unknowns, regiochemistry, rotamerization

• Quantitative NMR • Chemical exchange: Equilibrium or A(Di)ssociation constants • Reaction monitoring or reaction rates • Diffusion coefficients (DOSY NMR): monomer? dimer? • Enantiomeric purity determination • Absolute stereochemistry determination • Dynamics (T1, T2 and NOE) • Intramolecular hydrogen-bond determination • Parahydrogen-NMR (enhance NMR signals thousands fold) to study

reaction pathways

• NMR Screening (Protein-Ligand Interaction)

• Structure and Dynamics of Macromolecules and

Complexes (e.g., peptides and proteins)

• Metabolites Analysis

NM

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ab

Overv

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by Lingyang Zhu

Page 2: What NMR Can Do for You - University Of Illinois · 2019-04-02 · What NMR Can Do for You • Structure Elucidation of Small Molecules • Structure identification of synthetic compounds,

Count the Numbers

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13C-APT

1H Spectrum

Page 3: What NMR Can Do for You - University Of Illinois · 2019-04-02 · What NMR Can Do for You • Structure Elucidation of Small Molecules • Structure identification of synthetic compounds,

Long-Range Connectivity: 1H-13C gHMBC Spectrum

11 18 1 6 24 21

28

8

29,13209 25

29,25

28,25

22,25

26,2526,29

22,21

19,21

23,21

4,2

10,2

4,64,18

7,67,11

8,68,11

7,9

22,20

20,2424,18

6,1120,18

21,18

24,20

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Page 4: What NMR Can Do for You - University Of Illinois · 2019-04-02 · What NMR Can Do for You • Structure Elucidation of Small Molecules • Structure identification of synthetic compounds,

Relative Stereochemistry: 1D 1H-1H NOE Experiment

This problem can also be

readily solved by 1H-1H

J-coupling constants

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Page 5: What NMR Can Do for You - University Of Illinois · 2019-04-02 · What NMR Can Do for You • Structure Elucidation of Small Molecules • Structure identification of synthetic compounds,

Regioisomer: 1H-19F NOE Experiment

NOE seen between 19F and proton at position 3, but not to the

pyrazole proton, suggesting the 5-position reaction, not 1-

position.

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3

3 6

NOE spectrum

1H spectrum

Page 6: What NMR Can Do for You - University Of Illinois · 2019-04-02 · What NMR Can Do for You • Structure Elucidation of Small Molecules • Structure identification of synthetic compounds,

Regioisomer: 15N Chemical Shifts

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Based on the 15N chemical Shifts and

the connectivity from 1H-15N HMBC spectrum

Page 7: What NMR Can Do for You - University Of Illinois · 2019-04-02 · What NMR Can Do for You • Structure Elucidation of Small Molecules • Structure identification of synthetic compounds,

Variable Temperature Experiments:

Tautomer Identification

HN

O

R

N11

12

13

14t

15t

16tN

O

R

HN

11

12

13

14

15

16

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HP

LC

D

ata

H

PLC

D

ata

5°C

25°C

Page 8: What NMR Can Do for You - University Of Illinois · 2019-04-02 · What NMR Can Do for You • Structure Elucidation of Small Molecules • Structure identification of synthetic compounds,

qNMR: Determination of %TFA

by an Internal Standard

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Page 9: What NMR Can Do for You - University Of Illinois · 2019-04-02 · What NMR Can Do for You • Structure Elucidation of Small Molecules • Structure identification of synthetic compounds,

qNMR: Determining [sample]

using NMR software

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Page 10: What NMR Can Do for You - University Of Illinois · 2019-04-02 · What NMR Can Do for You • Structure Elucidation of Small Molecules • Structure identification of synthetic compounds,

M=(4 r3 N)/3

DOSY: Determination of MW

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MW=(4r3N)/3

D=kT/6r

Page 11: What NMR Can Do for You - University Of Illinois · 2019-04-02 · What NMR Can Do for You • Structure Elucidation of Small Molecules • Structure identification of synthetic compounds,

Chemical Exchange in NMR:

Intra- and Inter-molecular process

Kassoc = kon/koff

k1

k-1

Keq determined by LW and Dd

kon

koff

+

Intra-

Inter-

STD Experiments

Meyer: 2003

U. Ottawa NMR Facility

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Page 12: What NMR Can Do for You - University Of Illinois · 2019-04-02 · What NMR Can Do for You • Structure Elucidation of Small Molecules • Structure identification of synthetic compounds,

Collaborations & Publications Select Publications:

• A Metal-Free Electrocatalyst for Carbon Dioxide Reduction to Multi-Carbon Hydrocarbons and

Oxygenates. NatureComm 2016 (Kenis Group)

• Setting and Nanostructural Evolution of Metakaolin Geopolymers. JACERS 2016 (Struble

Group)

• Experimental evidence for a Co(I)/Co(III) redox process in olefin hydrogenation. JACS 2016

(Fout Group)

• Characterization of Sodium Mobility, Binding, and Apparent Viscosity in Full-Fat and Reduced-

Fat Model Emulsion Systems. JFMC 2016 (Schmidt Group)

• The interplay of Al and Mg speciation in advanced Mg battery electrolytes. JACS, 2015

(Gewirth Group)

• Control of protein orientation on gold nanoparticles. JPC, 2015 (Murphy group)

• Structure, bioactivity, and resistance mechanism of streptomonomicin, an unusual lasso peptide

from an understudied halophilic actnomycete. Chem Biol 2015 (Mitchell Group)

• Synthesis and Characterization of the Platinum-Substituted Keggin Anion α- H2SiPtW11O404-.

Inorg. Chem 2014 (Klemperer)

• Alkyne Mechanochemistry: Putative Activation by Transoidal Bending. RSC ChemComm. 2014

(Moore group)

• NMR structure of the S-linked glycopeptide sublancin 168. ACS Chem Biol. 2014 (van der

Donk group)

• New Reactions of Terminal Hydrides on a Diiron Dithiolate. JACS 2014 (Rauchfuss group)

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Page 13: What NMR Can Do for You - University Of Illinois · 2019-04-02 · What NMR Can Do for You • Structure Elucidation of Small Molecules • Structure identification of synthetic compounds,

LU

Thank you

Please visit us at http://scs.illinois.edu/nmr/

Questions Always Welcome

HuiHui, Xixi and Lu