تعیین ساختار ارگانیک با استفاده از طیف‌سنجی NMR دو بعدی، ویرایش دوم: رویکرد مبتنی بر مسئله

This book contains 60 quality 2D NMR data sets following an introductory section describing the methodology employed. Many other books describe the methods used, but none offer a large number of problems. Instructors at universities and colleges at the present time are forced to cobble together problems from a wide range of sources. The fragmentary approach to assembling course materials has a negative impact on course continuity and thus adversely impacts student retention. This book will stand as a single source to which instructors and students can go to obtain a comprehensive compendium of NMR problems of varying difficulty. • Presents strategies for assigning resonances to known structures and for deducing structures of unknown organic molecules based on their NMR spectra • Contains 30 known and 30 unknown structure determination problems • Features a supporting website from which instructors can download the structures of the unknowns in selected chapters, digital versions of all figures, and raw data sets for processing. Organic Structure Determination Using 2-D NMR Spectroscopy: A Problem-Based Approach......Page 1 Copyright......Page 2 Dedicated to......Page 3 Preface......Page 4 Preface to the First Edition......Page 6 1.1 What Is Nuclear Magnetic Resonance?......Page 8 1.2 Consequences of Nuclear Spin......Page 9 1.3 Application of a Magnetic Field to a Nuclear Spin......Page 11 1.4 Application of a Magnetic Field to an Ensemble of Nuclear Spins......Page 14 1.5 Tipping the Net Magnetization Vector from Equilibrium......Page 19 1.6 Signal Detection......Page 20 1.8 The 1-D NMR Spectrum......Page 21 1.9 The 2-D NMR Spectrum......Page 23 1.10 Information Content Available Using NMR Spectroscopy......Page 25 Problems for Chapter One......Page 26 2.1 Sample Preparation......Page 29 2.1.3 Solvent Selection......Page 30 2.1.4 Cleaning NMR Tubes Prior to Use or Reuse......Page 31 2.1.6 Sample Mixing......Page 32 2.2 Locking......Page 38 2.3 Shimming......Page 39 2.4 Temperature Regulation......Page 40 2.5 Modern NMR Instrument Architecture......Page 41 2.5.4 RF Filtering......Page 44 2.6 Pulse Calibration......Page 46 2.7 Sample Excitation and the Rotating Frame of Reference......Page 48 2.8 Pulse Rolloff......Page 49 2.9 Probe Variations......Page 54 2.9.1 Small-Volume NMR Probes......Page 55 2.10 Analog Signal Detection......Page 59 2.11 Signal Digitization......Page 60 References......Page 64 3.1 Setting the Spectral Window......Page 65 3.2 Determining the Optimal Wait 䐀攀氀愀礀 Between Scans......Page 68 3.3 Setting the Acquisition Time......Page 71 3.4 How Many Points to Acquire in a 1-D Spectrum......Page 72 3.5 Zero Filling and Digital Resolution......Page 73 3.6 Setting the Number of Points to Acquire in a 2-D Spectrum......Page 75 3.7 Truncation Error and Apodization......Page 77 3.8 The Relationship Between T2 * and Observed Line Width ......Page 79 3.10 Forward Linear Prediction......Page 81 3.11 Pulse Ringdown and Backward Linear Prediction31......Page 83 3.12 Phase Correction......Page 84 3.13 Baseline Correction39......Page 87 3.14 Integration......Page 89 3.15 Measurement of Chemical Shifts and J-Couplings......Page 93 3.16 Data Representation......Page 98 Problems for Chapter Three......Page 106 4.1 The Nature of the Chemical Shift......Page 107 4.2 Aliphatic Hydrocarbons......Page 110 4.4 Olefinic Hydrocarbons......Page 112 4.5 Acetylenic Hydrocarbons......Page 113 4.6 Aromatic Hydrocarbons......Page 114 4.7 Heteroatom Effects......Page 116 Problems for Chapter Four......Page 117 Reference......Page 118 5 Symmetry and Topicity ......Page 119 5.1 Homotopicity......Page 121 5.2 Enantiotopicity......Page 122 5.3 Diastereotopicity......Page 123 Problems for Chapter Five......Page 126 Reference......Page 127 6.1 Origin of J-Coupling......Page 129 6.2 Skewing of the Intensity of Multiplets......Page 133 6.3 Prediction of First-Order Multiplets......Page 136 6.4 The Karplus Relationship for Spins Separated by Three Bonds......Page 142 6.5 The Karplus Relationship for Spins Separated by Two Bonds......Page 144 6.7 Decoupling Methods......Page 147 6.8 One-Dimensional Experiments Utilizing J-Couplings......Page 150 6.9 Two-Dimensional Experiments Utilizing J-Couplings......Page 153 6.9.1.1.2 Absolute-value COSY, Including gCOSY......Page 155 6.9.1.3 INADEQUATE......Page 159 6.9.2.1 HMQC and HSQC......Page 160 6.9.2.2 HMBC......Page 168 Problems for Chapter Six......Page 172 References......Page 173 7.1 The Dipolar Relaxation Pathway......Page 174 7.2 The Energetics of an Isolated Heteronuclear Two-Spin System......Page 175 7.3 The Spectral Density Function......Page 177 7.5 Rapid Relaxation via the Double Quantum Pathway......Page 179 7.6 A One-Dimensional Experiment Utilizing the NOE......Page 182 7.7.2 ROESY......Page 186 Problems for Chapter Seven......Page 188 Reference......Page 189 8 Molecular Dynamics ......Page 190 8.1 Relaxation......Page 191 8.2 Rapid Chemical Exchange......Page 195 8.3 Slow Chemical Exchange......Page 196 8.4 Intermediate Chemical Exchange......Page 198 8.5 Two-Dimensional Experiments that Show Exchange......Page 200 Problems for Chapter Eight......Page 201 Reference......Page 202 9 Strategies for Assigning Resonances to Atoms within a Molecule......Page 203 9.1 Prediction of Chemical Shifts......Page 204 9.3 Prediction of 1H Multiplets......Page 205 9.4 Good Bookkeeping Practices......Page 206 9.5 Assigning 1H Resonances on the Basis of Chemical Shifts......Page 207 9.6 Assigning 1H Resonances on the Basis of Multiplicities......Page 208 9.7 Assigning 1H Resonances on the Basis of the gCOSY Spectrum......Page 211 9.8 The Best Way to Read a gCOSY Spectrum......Page 214 9.9 Assigning 13C Resonances on the Basis of Chemical Shifts......Page 215 9.10 Pairing 1H and 13C Shifts by Using the HSQC/HMQC Spectrum......Page 217 9.11 Assignment of Nonprotonated 13C's on the Basis of the HMBC Spectrum......Page 221 10 Strategies for Elucidating Unknown Molecular Structures ......Page 226 10.1 Initial Inspection of the One-Dimensional Spectra......Page 227 10.2 Good Accounting Practices......Page 230 10.4 Completion of Assignments......Page 233 Problem 11.1 2-Acetylbutyrolactone in CDCl3 匀愀洀瀀氀攀 (ᄀ)㘀......Page 240 Problem 11.2 α-Terpinene in CDCl3 匀愀洀瀀氀攀 (ᄀ)㠀......Page 243 Problem 11.10 Sucrose in D2O 匀愀洀瀀氀攀 (ᄀ)㄀......Page 286 Problem 12.5 ⴀ-Epicatechin in Acetone-d6 匀愀洀瀀氀攀 㔀㔀......Page 313 Problem 13.1 Unknown 13.1 in CDCl3 匀愀洀瀀氀攀 (ᄀ) ......Page 343 Problem 13.2 Unknown 13.2 in CDCl3 匀愀洀瀀氀攀 㐀㄀......Page 348 Problem 13.3 Unknown 13.3 in CDCl3 匀愀洀瀀氀攀 (ᄀ)(ᄀ)......Page 353 Problem 13.4 Unknown 13.4 in CDCl3 匀愀洀瀀氀攀 (ᄀ)㐀......Page 355 Problem 13.5 Unknown 13.5 in CDCl3 匀愀洀瀀氀攀 アパート㐀......Page 359 Problem 13.6 Unknown 13.6 in CDCl3 匀愀洀瀀氀攀 アパート㘀......Page 363 Problem 13.7 Unknown 13.7 in CDCl3 匀愀洀瀀氀攀 㔀 ......Page 365 Problem 13.8 Unknown 13.8 in CDCl3 匀愀洀瀀氀攀 㠀アパート......Page 370 Problem 13.9 Unknown 13.9 in CDCl3 匀愀洀瀀氀攀 㠀(ᄀ)......Page 374 Problem 13.10 Unknown 13.10 in CDCl3 匀愀洀瀀氀攀 㠀㐀......Page 376 Problem 14.1 Unknown 14.1 in CDCl3 匀愀洀瀀氀攀 アパート(ᄀ)......Page 382 Problem 14.2 Unknown 14.2 in CDCl3 匀愀洀瀀氀攀 アパートアパート......Page 387 Problem 14.3 Unknown 14.3 in CDCl3 匀愀洀瀀氀攀 㔀㄀......Page 392 Problem 14.4 Unknown 14.4 in CDCl3 匀愀洀瀀氀攀 㜀㐀......Page 397 Problem 14.5 Unknown 14.5 in CDCl3 匀愀洀瀀氀攀 㜀㔀......Page 401 Problem 14.6 Unknown 14.6 in CDCl3 匀愀洀瀀氀攀 㠀 ......Page 406 Problem 14.7 Unknown 14.7 in Acetone-d6 匀愀洀瀀氀攀 㠀㘀......Page 411 Problem 14.8 Unknown 14.8 in CDCl3 匀愀洀瀀氀攀 㠀㜀......Page 415 Problem 14.9 Unknown 14.9 in CDCl3 匀愀洀瀀氀攀 㠀㠀......Page 420 Problem 14.10 Unknown 14.10 in CDCl3 匀愀洀瀀氀攀 㜀(ᄀ)......Page 425 Problem 15.1 α-Cubebene in CDCl3 匀愀洀瀀氀攀 㤀㔀......Page 429 Problem 16.1 Unknown 16.1 in CDCl3 匀愀洀瀀氀攀 ㄀㄀㔀......Page 481 Problem 16.2 Unknown 16.2 in DMSO-d6 匀愀洀瀀氀攀 ㄀㄀㄀......Page 485 Problem 16.3 Unknown 16.3 in CDCl3 匀愀洀瀀氀攀 㤀㐀......Page 492 Problem 16.4 Unknown 16.4 in CDCl3 匀愀洀瀀氀攀 ㄀ 㐀......Page 497 Problem 16.5 Unknown 16.5 in DMSO-d6 匀愀洀瀀氀攀 ㄀ (ᄀ)......Page 501 Problem 16.6 Unknown 16.6 in CDCl3 匀愀洀瀀氀攀 㤀㜀......Page 506 Problem 16.7 Unknown 16.7 in CD3OD 匀愀洀瀀氀攀 㤀㠀......Page 510 Problem 16.10 Unknown 16.10 in CDCl3 匀愀洀瀀氀攀 ㄀ ㄀......Page 522 Glossary of Terms......Page 527 A......Page 556 C......Page 557 D......Page 559 E......Page 560 G......Page 561 H......Page 563 J......Page 564 M......Page 565 N......Page 566 O......Page 567 P......Page 568 R......Page 569 S......Page 570 T......Page 571 V......Page 572 Z......Page 573 This is a collection of 30-40 quality 2D NMR data sets following an introductory section describing the methodology employed. Many other books describe the methods used, but none offer a large number of problems. This book containsa60 quality 2D NMR data sets following an introductory section describing the methodology employed. Many other books describe the methods used, but none offer a large number of problems. Instructors at universities and colleges at the present time are forced to cobble together problems from a wide range of sources. The fragmentary approach to assembling course materials has a negative impact on course continuity and thus adversely impacts student retention. This book will stand as a single source to which instructors and students can go to obtain a comprehensive compendium of NMR problems of varying difficulty. . Presents strategies for assigning resonances to known structures and for deducing structures of unknown organic molecules based on their NMR spectra . Containsa30 known and 30 unknown structure determination problems . Features a supporting website from which instructors can download the structures of the unknowns in selected chapters, digital versions of all figures, and raw data sets for processing This book contains 60 quality 2D NMR data sets following an introductory section describing the methodology employed. Many other books describe the methods used, but none offer a large number of problems. Instructors at universities and colleges at the present time are forced to cobble together problems from a wide range of sources. The fragmentary approach to assembling course materials has a negative impact on course continuity and thus adversely impacts student retention. This book will stand as a single source to which instructors and students can go to obtain a comprehensive compendium of NMR problems of varying difficulty. . Presents strategies for assigning resonances to known structures and for deducing structures of unknown organic molecules based on their NMR spectra . Contains 20 known and 20 unknown structure determination problems . Features a supporting website from which instructors can download the structures of the unknowns in selected chapters, digital versions of all figures, and raw data sets for processing Machine generated contents note: PART I: Background and Methods Chapter 1: Introduction Chapter 2: Instrumental Considerations Chapter 3: Data Collection, Processing, and Plotting Chapter 4: 1H and 13C Chemical Shifts Chapter 5: Symmetry and Topicity Chapter 6: Through-Bond Effects: Spin-Spin (J) Coupling Chapter 7: Through-Space Effects: the Nuclear Overhauser Effect (NOE) Chapter 8: Molecular Dynamics Chapter 9: Strategies for Assigning Molecules Chapter 10: Strategies for Elucidating Unknown Molecular Structures PART II: Problems Chapter 11 Simple Assignment Problems Chapter 12: Complex Assignment Problems Chapter 13: Simple Unknown Problems Chapter 14: Complex Unknown Problems. "The second edition of this book comes with a number of new figures, passages, and problems. Increasing the number of figures from 290 to 448 has necessarily added considerable length, weight, and, expense. It is my hope that the book has not lost any of its readability and accessibility. I firmly believe that most of the concepts needed to learn organic structure determination using nuclear magnetic resonance spectroscopy do not require an extensive mathematical background. It is my hope that the manner in which the material contained in this book is presented both reflects and validates this belief"--