Organic Structures from 2D NMR Spectra (eBook)

Professor Leslie D. Field, Professor of Chemistry, University of New South Wales, Australia, has built up an international reputation for his research on novel reagents containing coordinatively unsaturated transition metals and for his extensive work in the field of NMR spectroscopy including novel studies on heteronuclear coherence transfer and multiple quantum NMR. Field was Professor of Organic Chemistry at the University of Sydney 1990 to 2005 and Head of the School of Chemistry from 1997 to 2001. He has also been the Deputy Vice Chancellor (Research) at UNSW since April 2005. Dr Alison Magill is a Postdoctoral Research Associate in the Field Group in the School of Chemistry, UNSW, with main areas of research in organometallic chemistry, catalysis and NMR spectroscopy, with a particular focus on the activation and functionalisation of small molecules such as carbon dioxide (CO2) and nitrogen (N2). Dr Hsiu Lin Li is a Postdoctoral Research Associate in the Field Group in the School of Chemistry, UNSW, with main areas of research in organometallic chemistry, catalysis and NMR spectroscopy, with a particular focus on the activation and functionalisation of small molecules such as carbon dioxide (CO2) and nitrogen (N2).

Preface vii

List of Figures xi

List of Tables xv

1 NMR Spectroscopy Basics 1

1.1 The Physics of Nuclear Spins 1

1.2 Basic NMR Instrumentation and the NMR Experiment 4

2 One-Dimensional Pulsed Fourier Transform NMR Spectroscopy 5

2.1 The Chemical Shift 7

2.2 1H NMR Spectroscopy 9

2.2.1 Chemical Shifts in 1H NMR Spectroscopy 9

2.2.2 Spin-Spin Coupling in 1H NMR Spectroscopy 10

2.2.3 Decoupling in 1H NMR Spectroscopy 15

2.2.4 The Nuclear Overhauser Effect in 1H NMR Spectroscopy 16

2.3 Carbon-13 NMR Spectroscopy 16

2.3.1 Decoupling in 13C NMR Spectroscopy 17

2.3.2 Chemical Shifts in 13C NMR Spectroscopy 18

2.4 Fluorine-19 NMR Spectroscopy 19

2.5 Phosphorus-31 NMR Spectroscopy 22

2.6 Nitrogen-15 NMR Spectroscopy 23

3 Two-Dimensional NMR Spectroscopy 25

3.1 General Principles 25

3.2 Proton-Proton Interactions 28

3.2.1 Correlation Spectroscopy - The COSY Experiment 28

3.2.2 Total Correlation Spectroscopy - The TOCSY Experiment 30

3.2.3 Nuclear Overhauser Spectroscopy - The NOESY Experiment 31

3.3 Carbon-Carbon Interactions 35

3.3.1 The INADEQUATE Experiment 35

3.4 Heteronuclear Correlation Spectroscopy 37

3.4.1 Heteronuclear Single Bond Correlation - The HSQC, HMQC and me-HSQC Experiments 37

3.4.2 Heteronuclear Multiple Bond Correlation - HMBC 38

4 Miscellaneous Topics 45

4.1 NMR Solvents 45

4.2 Reference Compounds and Standards 47

4.3 Dynamic Processes 48

4.3.1 Protons on Heteroatoms 49

4.3.2 Rotation about Partial Double Bonds 50

4.4 Second-Order Effects 51

4.5 Effect of a Chiral Centre on NMR Spectra 51

5 Worked Examples 55

5.1 General Principles 55

5.2 Worked Example 1 57

5.3 Worked Example 2 63

Problems 71

Index 309