Elementary Organic Spectroscopy

PRINCIPLES AND CHEMICAL APPLICATIONS FOR B.SC.(HONS) POST GRADUATE STUDENTS OF ALL INDIAN UNIVERSITIES AND COMPETITIVE EXAMINATIONS.

Appropriate for courses in organic spectroscopy or organic spectroscopic techniques in senior undergraduate and graduate programs. This text authoritatively covers currently used techniques for determining the structure of organic and biological compounds ideal for any practicing or future organic or biochemist. The fundamentals of all four principal spectroscopic methods are covered in depth, each by an experienced author who is a practicing expert in that area. The material is easy to grasp, beginning at the most elementary level and progressing to the level required for organic research. Highlights include the most thorough and current treatment of NMR available, ample problem material, and two new chapters devoted to multiple pulse and two-dimensional methods.

A unique textbook, aimed at undergraduate students, containing large numbers of spectra, problems and marginal notes, specifically chosen to highlight the points being discussed.

Nuclear magnetic resonance (NMR) spectroscopy is one of the most powerful and widely used techniques in chemical research for investigating structures and dynamics of molecules. Advanced methods can even be utilized for structure determinations of biopolymers, for example proteins or nucleic acids. NMR is also used in medicine for magnetic resonance imaging (MRI). The method is based on spectral lines of different atomic nuclei that are excited when a strong magnetic field and a radiofrequency transmitter are applied. The method is very sensitive to the features of molecular structure because also the neighboring atoms influence the signals from individual nuclei and this is important for determining the 3D-structure of molecules. This new edition of the popular classic has a clear style and a highly practical, mostly non-mathematical approach. Many examples are taken from organic and organometallic chemistry, making this book an invaluable guide to undergraduate and graduate students of organic chemistry, biochemistry, spectroscopy or physical chemistry, and to researchers using this well-established and extremely important technique. Problems and solutions are included.

Though the format evolved in the first edition remains intact, relevant new additions have been inserted at appropriate places in various chapters of the book. Also included are a number of sample and study problems at the end of each chapter to illustrate the approach to problem solving that involve translations of sets of spectra into chemical structures. Written primarily to stimulate the interest of students in spectroscopy and make them aware of the latest developments in this field, this book begins with a general introduction to electromagnetic radiation and molecular spectroscopy. In addition to the usual topics on IR, UV, NMR and Mass spectrometry, it includes substantial material on the currently useful techniques such as FT-IR, FT-NMR 13C-NMR, 2D-NMR, GC/MS, FAB/MS, Tendem and Negative Ion Mass Spectrometry for students engaged in advanced studies. Finally it gives a detailed account on Optical Rotatory Dispersion (ORD) and Circular Dichroism (CD).

Chapter 1 Introduction 1-1 The Spectroscopic Approach to Structure Determination 1-2 Contributions of Different Forms of Spectroscopy 1-3 The Electromagnetic Spectrum 1-4 Molecular Weight and Molecular Formula 1-5 Structural Isomers and Stereoisomers Problems Part I NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY Chapter 2 Introduction 2-1 Magnetic Properties of Nuclei 2-2 The Chemical Shift 2-3 Excitation and Relaxation 2-4 Pulsed Experiments 2-5 The Coupling Constant 2-6 Quantification and Complex Splitting 2-7 Commonly Studied Nuclides 2-8 Dynamic Effects 2-9 Spectra of Solids 2-10 Experimental Methods Problems Tips on Solving NMR Problems Bibliography Chapter 3 The Chemical Shift 3-1 Factors That Influence Proton Shifts 3-2 Proton Chemical Shifts and Structure 3-3 Medium and Isotope Effects 3-4 Factors That Influence Carbon Shirts 3-5 Carbon Chemical Shifts and Structure 3-6 Tables of Chemical Shifts Problems Further Tips on Solving NMR Problems Bibliography Chapter 4 The Coupling Constant 4-1 First-Order Spectra 4-2 Chemical and Magnetic Equivalence 4-3 Signs and Mechanisms 4-4 Couplings over One Bond 4-5 Geminal Couplings 4-6 Vicinal Couplings 4-7 Long-Range Couplings 4-8 Spectral Analysis 4-9 Second-Order Spectra 4-10 Tables of Coupling Constants Problems Bibliography Chapter 5 Further Topics in One-Dimensional NMR 5-1 Spin-Lattice and Spin-Spin Relaxation 5-2 Reactions on the NMR Time Scale 5-3 Multiple Resonance 5-4 The Nuclear Overhauser Effect 5-5 Spectral Editing 5-6 Sensitivity Enhancement 5-7 Carbon Connectivity 5-8 Phase Cycling, Composite Pulses, and Shaped Pulses Problems Bibliography Chapter 6 Two-Dimensional NMR 6-1 Proton-Proton Correlation Through Coupling 6-2 Proton-Heteronucleus Correlation 6-3 Proton-Proton Correlation Through Space or Chemical Exchange 6-4 Carbon-Carbon Correlation 6-5 Higher Dimensions 6-6 Pulsed Field Gradients 6-7 Summary of Two-Dimensional Methods Problems Bibliography Part II MASS SPECTROMETRY Chapter 7 Instrumentation and Theory 7-1 Introduction 7-2 Ionization Methods 7-3 Mass Analysis 7-4 Sample Preparation Chapter 8 Ion Activation and Fragmentation 8-1 Basic Principles 8-2 Methods and Energetics 8-3 Functional Groups Chapter 9 Structural Analysis 9-1 Molecular Weights 9-2 Molecular Formula 9-3 Structures from Fragmentation Patterns 9-4 Polymers Chapter 10 Quantitative Applications 10-1 Quantification of Analytes 10-2 Thermochemistry Part III VIBRATIONAL SPECTROSCOPY Chapter 11 Introduction 11-1 Introduction 11-2 Vibrations of Molecules 11-3 Infrared and Raman Spectra 11-4 Units and Notation 11-5 Infrared Spectra: Dispersive and Fourier Transform 11-6 Sampling Methods for Infrared Transmission Spectra 11-7 Raman Spectroscopy 11-8 Raman Sampling Methods 11-9 Depolarization Measurements 11-10 Infrared Reflection Spectroscopy Problems Bibliography Chapter 12 Group Frequencies 12-1 Introduction 12-2 Factors Affecting Group Frequencies 12-3 Infrared Group Frequencies 12-4 Raman Group Frequencies 12-5 Preliminary Analysis 12-6 The CH Stretching Region (3340-2700 cm-1) 12-7 The Carbonyl Stretching Region (1850-1650 cm-1) 12-8 Aromatic Compounds 12-9 Compounds Containing Methyl Groups 12-10 Compounds Containing Methylene Groups 12-11 Unsaturated Compounds 12-12 Compounds Containing Oxygen 12-13 Compounds Containing Nitrogen 12-14 Compounds Containing Phosphorus and Sulfur 12-15 Heterocyclic Compounds 12-16 Compounds Containing Halogens 12-17 Boron, Silicon, Tin, Lead, and Mercury Compounds 12-18 Isotopically Labeled Compounds 12-19 Using the Literature on Vibrational Spectroscopy Problems Bibliography Part IV ELECTRONIC ABSORPTION SPECTROSCOPY Chapter 13 Introduction and Experimental Methods 13-1 Introduction 13-2 Measurement of Ultraviolet-Visible Light Absorption 13-3 Quantitative Measurements 13-4 Electronic Transitions 13-5 Experimental Aspects Problems Bibliography Chapter 14 Structural Analysis 14-1 Isolated Chromophores 14-2 Conjugated Chromophores 14-3 Aromatic Compounds 14-4 Important Naturally Occurring Chromophores 14-5 The Woodward-Fieser Rules 14-6 Steric Effects 14-7 Solvent Effects and Dynamic Equilibria 14-8 Hydrogen Bonding Studies 14-9 Homoconjugation 14-10 Charge Transfer Band 14-11 Worked Problems Problems Bibliography Chapter 15 Integrated Problems

Offers a realistic approach to solving problems used by organic chemists. Covering all the major spectroscopic techniques, it provides a graded set of problems that develop and consolidate students' understanding of organic spectroscopy. This edition contains more elementary problems and a modern approach to NMR spectra.