200 and More NMR Experiments: A Practical Course

Preface v

Chapter 1 The NMR Spectrometer 1

1.1 Components of an NMR Spectrometer 1

1.1.1 The Magnet 1

1.1.2 The Spectrometer Cabinet 2

1.1.3 The Computer 3

1.1.4 Maintenance 3

1.2 Tuning a Probe-Head 3

1.3 The Lock Channel 4

1.4 The Art of Shimming 6

1.4.1 The Shim Gradients 6

1.4.2 The Shimming Procedure 8

1.4.3 Gradient Shimming 11

Chapter 2 Determination of Pulse-Duration 14

Exp. 2.1: Determination of the 90° 1H Transmitter Pulse-Duration 15

Exp. 2.2: Determination of the 90° 13C Transmitter Pulse-Duration 18

Exp. 2.3: Determination of the 90° 1H Decoupler Pulse-Duration 21

Exp. 2.4: The 90° 1H Pulse with Inverse Spectrometer Configuration 24

Exp. 2.5: The 90° 13C Decoupler Pulse with Inverse Configuration 27

Exp. 2.6: Composite Pulses 30

Exp. 2.7: Radiation Damping 33

Exp. 2.8: Pulse and Receiver Phases 36

Exp. 2.9: Determination of Radiofrequency Power 39

Chapter 3 Routine NMR Spectroscopy and Standard Tests 43

Exp. 3.1: The Standard 1H NMR Experiment 44

Exp. 3.2: The Standard 13C NMR Experiment 49

Exp. 3.3: The Application of Window Functions 54

Exp. 3.4: Computer-Aided Spectral Analysis 58

Exp. 3.5: Line Shape Test for 1H NMR Spectroscopy 61

Exp. 3.6: Resolution Test for 1H NMR Spectroscopy 64

Exp. 3.7: Sensitivity Test for 1H NMR Spectroscopy 67

Exp. 3.8: Line Shape Test for 13C NMR Spectroscopy 70

Exp. 3.9: ASTM Sensitivity Test for 13C NMR Spectroscopy 73

Exp. 3.10: Sensitivity Test for 13C NMR Spectroscopy 76

Exp. 3.11: Quadrature Image Test 79

Exp. 3.12: Dynamic Range Test for Signal Amplitudes 82

Exp. 3.13: 13° Phase Stability Test 85

Exp. 3.14: Radiofrequency Field Homogeneity 88

Chapter 4 Decoupling Techniques 91

Exp. 4.1: Decoupler Calibration for Homonuclear Decoupling 92

Exp. 4.2: Decoupler Calibration for Heteronuclear Decoupling 95

Exp. 4.3: Low-Power Calibration for Heteronuclear Decoupling 98

Exp. 4.4: Homonuclear Decoupling 101

Exp. 4.5: Homonuclear Decoupling at Two Frequencies 104

Exp. 4.6: The Homonuclear SPT Experiment 107

Exp. 4.7: The Heteronuclear SPT Experiment 110

Exp. 4.8: The Basic Homonuclear NOE Difference Experiment 113

Exp. 4.9: 1D Nuclear Overhauser Difference Spectroscopy 116

Exp. 4.10: 1D NOE Spectroscopy with Multiple Selective Irradiation 119

Exp. 4.11: 1H Off-Resonance Decoupled 13C NMR Spectra 122

Exp. 4.12: The Gated 1H-Decoupling Technique 125

Exp. 4.13: The Inverse Gated 1H-Decoupling Technique 128

Exp. 4.14: 1H Single-Frequency Decoupling of 13C NMR Spectra 131

Exp. 4.15: 1H Low-Power Decoupling of 13C NMR Spectra 134

Exp. 4.16: Measurement of the Heteronuclear Overhauser Effect 137

Chapter 5 Dynamic NMR Spectroscopy 140

Exp. 5.1: Low-Temperature Calibration Using Methanol 141

Exp. 5.2: High-Temperature Calibration Using 1,2-Ethanediol 145

Exp. 5.3: Dynamic 1H NMR Spectroscopy on Dimethylformamide 149

Exp. 5.4: The Saturation Transfer Experiment 152

Exp. 5.5: Measurement of the Rotating-Frame Relaxation Time T1ρ 155

Chapter 6 1D Multipulse Sequences 159

Exp. 6.1: Measurement of the Spin−Lattice Relaxation Time T1 160

Exp. 6.2: Measurement of the Spin−Spin Relaxation Time T2 164

Exp. 6.3: 13C NMR Spectra with SEFT 167

Exp. 6.4: 13C NMR Spectra with APT 170

Exp. 6.5: The Basic INEPT Technique 173

Exp. 6.6: INEPT+ 176

Exp. 6.7: Refocused INEPT 179

Exp. 6.8: Reverse INEPT 182

Exp. 6.9: DEPT-135 185

Exp. 6.10: Editing 13C NMR Spectra Using DEPT 188

Exp. 6.11: DEPTQ 191

Exp. 6.12: Multiplicity Determination Using PENDANT 194

Exp. 6.13: 1D-INADEQUATE 197

Exp. 6.14: The BIRD Filter 201

Exp. 6.15: TANGO 204

Exp. 6.16: The Heteronuclear Double-Quantum Filter 207

Exp. 6.17: Purging with a Spin-Lock Pulse 210

Exp. 6.18: Water Suppression by Presaturation 213

Exp. 6.19: Water Suppression by the Jump-and-Return Method 216

Chapter 7 NMR Spectroscopy with Selective Pulses 219

Exp. 7.1: Determination of a Shaped 90° 1H Transmitter Pulse 220

Exp. 7.2: Determination of a Shaped 90° 1H Decoupler Pulse 223

Exp. 7.3: Determination of a Shaped 90° 13C Decoupler Pulse 226

Exp. 7.4: Selective Excitation Using DANTE 229

Exp. 7.5: SELCOSY 232

Exp. 7.6: SELINCOR: Selective Inverse H,C Correlation via 1J(C,H) 235

Exp. 7.7: SELINQUATE 238

Exp. 7.8: Selective TOCSY 242

Exp. 7.9: INAPT 246

Exp. 7.10: Determination of Long-Range C,H Coupling Constants 249

Exp. 7.11: SELRESOLV 252

Exp. 7.12: SERF 255

Chapter 8 Auxiliary Reagents, Quantitative Determinations, and Reaction Mechanisms 258

Exp. 8.1: Signal Separation Using a Lanthanide Shift Reagent 259

Exp. 8.2: Signal Separation of Enantiomers Using a Chiral Shift Reagent 262

Exp. 8.3: Signal Separation of Enantiomers Using a Chiral Solvating Agent 265

Exp. 8.4: Determination of Enantiomeric Purity with Pirkle’s Reagent 268

Exp. 8.5: Determination of Enantiomeric Purity by 31P NMR 271

Exp. 8.6: Determination of Absolute Configuration by the Advanced Mosher Method 274

Exp. 8.7: Aromatic Solvent-Induced Shift (ASIS) 277

Exp. 8.8: NMR Spectroscopy of OH Protons and H/D Exchange 280

Exp. 8.9: Water Suppression Using an Exchange Reagent 283

Exp. 8.10: Isotope Effects on Chemical Shielding 286

Exp. 8.11: pKa Determination by 13C NMR 290

Exp. 8.12: Determination of Association Constants Ka 293

Exp. 8.13: Saturation Transfer Difference NMR 298

Exp. 8.14: The Relaxation Reagent Cr(acac)3 302

Exp. 8.15: Determination of Paramagnetic Susceptibility by NMR 305

Exp. 8.16: 1H and 13C NMR of Paramagnetic Compounds 308

Exp. 8.17: The CIDNP Effect 312

Exp. 8.18: Quantitative 1H NMR Spectroscopy: Determination of the Alcohol Content of Polish Vodka 315

Exp. 8.19: Quantitative 13C NMR Spectroscopy with Inverse Gated 1H-Decoupling 318

Exp. 8.20: NMR Using Liquid-Crystal Solvents 321

Chapter 9 Heteronuclear NMR Spectroscopy 324

Exp. 9.1: 1H-Decoupled 15N NMR Spectra Using DEPT 330

Exp. 9.2: 1H-Coupled 15N NMR Spectra Using DEPT 333

Exp. 9.3: 19F NMR Spectroscopy 336

Exp. 9.4: 29Si NMR Spectroscopy Using DEPT 339

Exp. 9.5: 29Si NMR Spectroscopy Using Spin-Lock Polarization 342

Exp. 9.6: 119Sn NMR Spectroscopy 346

Exp. 9.7: 2H NMR Spectroscopy 349

Exp. 9.8: 11B NMR Spectroscopy 352

Exp. 9.9: 17O NMR Spectroscopy Using RIDE 355

Exp. 9.10: 47/49Ti NMR Spectroscopy Using ARING 358

Chapter 10 The Second Dimension 362

Exp. 10.1: 2D J-Resolved 1H NMR Spectroscopy 367

Exp. 10.2: 2D J-Resolved 13C NMR Spectroscopy 370

Exp. 10.3: The Basic H,H-COSY Experiment 373

Exp. 10.4: Long-Range COSY 377

Exp. 10.5: Phase-Sensitive COSY 380

Exp. 10.6: Phase-Sensitive COSY-45 383

Exp. 10.7: E.COSY 386

Exp. 10.8: Double-Quantum-Filtered COSY with Presaturation 389

Exp. 10.9: Fully Coupled C,H Correlation (FUCOUP) 393

Exp. 10.10: C,H-Correlation by Polarization Transfer (HETCOR) 396

Exp. 10.11: Long-Range C,H-Correlation by Polarization Transfer 399

Exp. 10.12: C,H Correlation via Long-Range Couplings (COLOC) 402

Exp. 10.13: The Basic HMQC Experiment 405

Exp. 10.14: Phase-Sensitive HMQC with BIRD Filter and GARP Decoupling 409

Exp. 10.15: Poor Man’s Gradient HMQC 412

Exp. 10.16: Phase-Sensitive HMBC with BIRD Filter 415

Exp. 10.17: The Basic HSQC Experiment 418

Exp. 10.18: The HOHAHA or TOCSY Experiment 422

Exp. 10.19: HETLOC 426

Exp. 10.20: The NOESY Experiment 430

Exp. 10.21: The CAMELSPIN or ROESY Experiment 434

Exp. 10.22: The HOESY Experiment 438

Exp. 10.23: 2D-INADEQUATE 441

Exp. 10.24: The EXSY Experiment 445

Exp. 10.25: X,Y-Correlation 448

Chapter 11 1D NMR Spectroscopy with Pulsed Field Gradients 453

Exp. 11.1: Calibration of Pulsed Field Gradients 455

Exp. 11.2: Gradient Pre-emphasis 458

Exp. 11.3: Gradient Amplifier Test 461

Exp. 11.4: Determination of Pulsed Field Gradient Ring-Down Delays 464

Exp. 11.5: The Pulsed Field Gradient Spin-Echo Experiment 467

Exp. 11.6: Excitation Pattern of Selective Pulses 470

Exp. 11.7: The Gradient Heteronuclear Double-Quantum Filter 474

Exp. 11.8: The Gradient zz-Filter 477

Exp. 11.9: The Gradient-Selected Dual Step Low-Pass Filter 480

Exp. 11.10: gs-SELCOSY 484

Exp. 11.11: gs-SELTOCSY 488

Exp. 11.12: DPFGSE-NOE 492

Exp. 11.13: gs-SELINCOR 496

Exp. 11.14: α/β-SELINCOR-TOCSY 499

Exp. 11.15: GRECCO 503

Exp. 11.16: WATERGATE 506

Exp. 11.17: Water Suppression by Excitation Sculpting 509

Exp. 11.18: Solvent Suppression Using WET 512

Exp. 11.19: DOSY 515

Exp. 11.20: INEPT-DOSY 518

Exp. 11.21: DOSY-HMQC 521

Chapter 12 2D NMR Spectroscopy With Field Gradients 525

Exp. 12.1: gs-COSY 526

Exp. 12.2: Constant-Time COSY 530

Exp. 12.3: Phase-Sensitive gs-DQF-COSY 534

Exp. 12.4: gs-HMQC 538

Exp. 12.5: gs-HMBC 542

Exp. 12.6: ACCORD-HMBC 546

Exp. 12.7: HMSC 550

Exp. 12.8: Phase-Sensititive gs-HSQC with Sensitivity Enhancement 554

Exp. 12.9: Edited HSQC with Sensitivity Enhancement 558

Exp. 12.10: HSQC with Adiabatic Pulses for High-Field Instruments 563

Exp. 12.11: gs-TOCSY 567

Exp. 12.12: gs-HMQC-TOCSY 571

Exp. 12.13: gs-HETLOC 575

Exp. 12.14: gs-J-Resolved HMBC 581

Exp. 12.15: 2Q-HMBC 585

Exp. 12.16: 1H-Detected 2D INEPT-INADEQUATE 589

Exp. 12.17: 1,1-ADEQUATE 593

Exp. 12.18: 1,n-ADEQUATE 597

Exp. 12.19: gs-NOESY 601

Exp. 12.20: gs-HSQC-NOESY 604

Exp. 12.21: gs-HOESY 608

Exp. 12.22: 1H,15N Correlation with gs-HMQC 612

Chapter 13 The Third Dimension 616

Exp. 13.1: 3D HMQC-COSY 618

Exp. 13.2: 3D gs-HSQC-TOCSY 622

Exp. 13.3: 3D H,C,P-Correlation 626

Exp. 13.4: 3D HMBC 630

Chapter 14 Solid-State NMR Spectroscopy 634

Exp. 14.1: Shimming Solid-State Probe-Heads 635

Exp. 14.2: Adjusting the Magic Angle 639

Exp. 14.3: Hartmann−Hahn Matching 642

Exp. 14.4: The Basic CP/MAS Experiment 645

Exp. 14.5: TOSS 649

Exp. 14.6: SELTICS 653

Exp. 14.7: Connectivity Determination in the Solid State 656

Exp. 14.8: REDOR 659

Exp. 14.9: High-Resolution Magic-Angle Spinning 663

Chapter 15 Protein NMR 666

Exp. 15.1: Pulse Determination for Protein NMR 670

Exp. 15.2: HN-HSQC 673

Exp. 15.3: HC-HSQC 678

Exp. 15.4: MUSIC 682

Exp. 15.5: HN-Correlation using TROSY 688

Exp. 15.6: HN-TOCSY-HSQC 692

Exp. 15.7: HNCA 698

Exp. 15.8: HN(CO)CA 705

Exp. 15.9: HNCO 711

Exp. 15.10: HN(CA)CO 718

Exp. 15.11: HCACO 725

Exp. 15.12: HCCH-TOCSY 732

Exp. 15.13: CBCANH 739

Exp. 15.14: CBCA(CO)NH 746

Exp. 15.15: HBHA(CBCACO)NH 753

Exp. 15.16: HN(CA)NNH 760

Exp. 15.17: HN-NOESY-HSQC 766

Exp. 15.18: HC-NOESY-HSQC 773

Exp. 15.19: 3D HCN-NOESY 779

Exp. 15.20: HNCA-J 785

Appendix 1 791

Pulse Programs

Appendix 2 794

Instrument Dialects

Appendix 3 797

Classification of Experiments

Appendix 4 799

Elementary Product Operator Formalism Rules

Appendix 5 802

Chemical Shift and Spin-Coupling Data for Ethyl Crotonate and Strychnine

Glossary and Index 804