Download or read book Carbon 13 NMR Chemical Shifts in Structural and Stereochemical Analysis written by Kalevi Pihlaja and published by VCH Publishers. This book was released on 1994 with total page 408 pages. Available in PDF, EPUB and Kindle. Book excerpt: A review of recent research on strategies and applications of the C-13 chemical shift, a method for determining configuration of organic compounds. Introduces C-13 NMR spectroscopy, and describes conditions for collecting the FID, for data handling, and for obtaining a well- resolved C-13 NMR spectrum, as well as various substituent effect correlations, their derivations, and the origin of the effects. Also discusses the use of multidimensional NMR methods. For organic, physical, and natural products chemists. Includes bandw diagrams. Annotation copyright by Book News, Inc., Portland, OR

Download or read book Carbon 13 NMR of Flavonoids written by P.K. Agrawal and published by Elsevier. This book was released on 2013-10-22 with total page 581 pages. Available in PDF, EPUB and Kindle. Book excerpt: This detailed treatise is written for chemists who are not NMR spectroscopists but who wish to use carbon-13 NMR spectroscopy. It shows why measurement of carbon-13 NMR is needed and explains how the method can - or should - be used for rapid characterization of flavonoids, one of the most diverse and widespread groups of natural constituents. The first part of the book presents background information and discussion of the essential aspects of flavonoids and carbon-13 NMR spectroscopy and demonstrates its significant role in the revision of several earlier established chemical structures. It discusses various one- and two-dimensional NMR spectroscopic techniques and other relevant experimental methodologies for the interpretation of spectral details which enable individual resonance lines to be associated with the appropriate carbons in a molecule. The second part provides a comprehensive coverage of the carbon-13 chemical shifts of various classes and subclasses of flavonoids. It also illustrates how to utilize carbon-13 data to gain information for the determination of the nature, number and site of any substituent in flavonoids. Vital information for the differential and complete structure elucidation of the various classes of flavonoids by carbon-13 NMR shielding data is described in-depth in the third part of the book. The book will be welcomed by all those working in natural product chemistry who will appreciate the non-mathematical approach and the fact that such a wealth of theoretical and practical information has been assembled in a single volume.

Download or read book The Flavonoids written by Jeffrey B. Harborne and published by Springer. This book was released on 2013-11-11 with total page 1218 pages. Available in PDF, EPUB and Kindle. Book excerpt: The flavonoids, one of the most numerous and widespread groups of natural constituents, are important to man not only because they contribute to plant colour but also because many members (e.g. coumestrol, phloridzin, rotenone) are physiologically active. Nearly two thousand substances have been described and as a group they are universally distributed among vascular plants. Although the anthocyanins have an undisputed function as plant pigments, the raison d'etre for the more widely distributed colourless flavones and flavonols still remains a mystery. It is perhaps the challenge of discovering these yet undisc10sed functions which has caused the considerable resurgence of interest in flavonoids during the last decade. This book attempts to summarize progress that has been made in the study of these constituents since the first comprehensive monograph on the chemistry of the flavonoid compounds was published, under the editorship of T. A. Geissman, in 1962. The present volume is divided into three parts. The first section (Chapters 1-4) deals with advances in chemistry, the main emphasis being on spectral techniques to take into account the re cent successful applications of NMR and mass spectral measurements to structural identifications. Recent developments in isolation techniques and in synthesis are also covered in this section. Advances in chemical knowledge of individual c1asses of flavonoid are mentioned inter aha in later chapters of the book.

Download or read book Carbon 13 NMR Spectral Problems written by Robert B. Bates and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 280 pages. Available in PDF, EPUB and Kindle. Book excerpt: With the advent of Fourier transform spectrometers of great sensitivity, it has become practical to obtain carbon-13 nuclear magnetic resonance (C-13 NMR; l3C NMR; CMR) spectra routinely on organic molecules, and this technique has become one of the highest utility in determining structures of organic unknowns. When the usual spectrometric techniques proton magnetic resonance (H-I NMR; IH NMR; PMR), infrared (lR), mass (MS), and ultraviolet (UV)-do not readily reveal a compound's structure, a C-13 NMR spectrum will often provide sufficient additional information to yield it unequivocally. With this in mind, the present work was designed to give advanced undergraduates, graduate students, and practicing chemists a working knowledge of and facility with the use of this valuable technique. Some familiarity with other spectrometric techniques is assumed (recommended book: Silverstein, Bassler, and Morrill, Spectrometric Identification of Organic Compounds), but no prior knowledge of C-13 NMR -which is treated very lightly, if at all, in the widely used elementary organic texts-is necessary. A discussion of C-13 NMR spectroscopy is followed by 125 problems, each consisting of a molecular formula, two types of C-13 NMR spectra (partially and completely proton decoupled, with connecting lines to facilitate multiplicity assignments), an integrated H-I NMR spectrum, and the most important IR, UV, and MS data. These problems have been very carefully prepared, thoroughly tested by students at the University of Arizona, and we believe that very few errors remain.

Download or read book Basic 1H and 13C NMR Spectroscopy written by Metin Balci and published by Elsevier. This book was released on 2005-01-19 with total page 441 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nuclear Magnetic Resonance (NMR) spectroscopy is a powerful and theoretically complex analytical tool. Basic 1H- and 13C-NMR Spectroscopy provides an introduction to the principles and applications of NMR spectroscopy. Whilst looking at the problems students encounter when using NMR spectroscopy, the author avoids the complicated mathematics that are applied within the field. Providing a rational description of the NMR phenomenon, this book is easy to read and is suitable for the undergraduate and graduate student in chemistry. Describes the fundamental principles of the pulse NMR experiment and 2D NMR spectra Easy to read and written with the undergraduate and graduate chemistry student in mind Provides a rational description of NMR spectroscopy without complicated mathematics

Download or read book Carbon 13 NMR Shift Assignments of Amines and Alkaloids written by M. Shamma and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 302 pages. Available in PDF, EPUB and Kindle. Book excerpt: The aim of this book is to gather under one cover most of the data presently available on the carbon-13 nuclear magnetic resonance (cmr) spectra of alkaloids. The term "alkaloids" is used here in a very broad sense to include synthetic analogues of the natural products. Simple model amines are also incorporated since these often supply the basic information required in the assignment of chemical shifts for the more complex compounds. The literature on alkaloid cmr spectroscopy has been covered through 1977, but the collec tion of compounds presented here is illustrative rather than exhaustive. The papers included in the reference list afford further information not only on the cmr assignments of the particular compounds provided here, but also incorporate data on additional related structures. Only a few dimeric indole alkaloids are included since to a large extent their cmr spectra can be corre lated directly with those of their monomeric analogues. The present volume is thus a representative empirical compendium of cmr assignments focusing upon alkaloids and model amines, and is intended to aid cmr research in heterocyclic and alkaloid chemistry. The compounds and data presented in this book are classified and organized according to structural similarity. The purpose of such a presenta tion is to demonstrate the common cmr characteristics of a given structural type, while also facilitating an empirical evaluation of the cmr spectral changes specifically reSUlting from relatively minor variations in oxidation level, substitution, or stereochemistry.

Download or read book Carbon 13 NMR Spectroscopy written by Eberhard Breitmaier and published by Wiley-VCH. This book was released on 1987 with total page 540 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Carbon 13 NMR Spectroscopy written by J Stothers and published by Elsevier. This book was released on 2012-12-02 with total page 575 pages. Available in PDF, EPUB and Kindle. Book excerpt: Carbon-13 NMR Spectroscopy focuses on the potential of 13C techniques and the practical difficulties associated with the detection of 13C NMR absorption. This monograph includes a descriptive presentation of 13C shielding results that has been adopted with emphasis on the structural and stereochemical aspects. Organized into four parts encompassing 11 chapters, this book starts with an overview of the characteristics of the NMR signals derived from compounds containing 13C nuclei in natural abundance that are inherently much weaker than those exhibited by protons. This monograph then compares the primary characteristics of 13C NMR with the more familiar proton methods. Other chapters consider the 13C spectra of pyridine, pyridazine, pyrimidine, pyrazine, s-triazine, and s-tetrazine. The final chapter deals with the effects of solute–solvent interactions on the shieldings of other nuclei. This monograph is intended for organic chemists, graduate students, and researchers in various branches of chemistry with an interest in 13C NMR methods as another approach to chemical problems.

Download or read book Methodologies for Metabolomics written by Norbert W. Lutz and published by Cambridge University Press. This book was released on 2013-01-21 with total page 641 pages. Available in PDF, EPUB and Kindle. Book excerpt: Metabolomics, the global characterisation of the small molecule complement involved in metabolism, has evolved into a powerful suite of approaches for understanding the global physiological and pathological processes occurring in biological organisms. The diversity of metabolites, the wide range of metabolic pathways and their divergent biological contexts require a range of methodological strategies and techniques. Methodologies for Metabolomics provides a comprehensive description of the newest methodological approaches in metabolomic research. The most important technologies used to identify and quantify metabolites, including nuclear magnetic resonance and mass spectrometry, are highlighted. The integration of these techniques with classical biological methods is also addressed. Furthermore, the book presents statistical and chemometric methods for evaluation of the resultant data. The broad spectrum of topics includes a vast variety of organisms, samples and diseases, ranging from in vivo metabolomics in humans and animals to in vitro analysis of tissue samples, cultured cells and biofluids.

Download or read book Understanding NMR Spectroscopy written by James Keeler and published by John Wiley & Sons. This book was released on 2011-09-19 with total page 533 pages. Available in PDF, EPUB and Kindle. Book excerpt: This text is aimed at people who have some familiarity with high-resolution NMR and who wish to deepen their understanding of how NMR experiments actually ‘work’. This revised and updated edition takes the same approach as the highly-acclaimed first edition. The text concentrates on the description of commonly-used experiments and explains in detail the theory behind how such experiments work. The quantum mechanical tools needed to analyse pulse sequences are introduced set by step, but the approach is relatively informal with the emphasis on obtaining a good understanding of how the experiments actually work. The use of two-colour printing and a new larger format improves the readability of the text. In addition, a number of new topics have been introduced: How product operators can be extended to describe experiments in AX2 and AX3 spin systems, thus making it possible to discuss the important APT, INEPT and DEPT experiments often used in carbon-13 NMR. Spin system analysis i.e. how shifts and couplings can be extracted from strongly-coupled (second-order) spectra. How the presence of chemically equivalent spins leads to spectral features which are somewhat unusual and possibly misleading, even at high magnetic fields. A discussion of chemical exchange effects has been introduced in order to help with the explanation of transverse relaxation. The double-quantum spectroscopy of a three-spin system is now considered in more detail. Reviews of the First Edition “For anyone wishing to know what really goes on in their NMR experiments, I would highly recommend this book” – Chemistry World “...I warmly recommend for budding NMR spectroscopists, or others who wish to deepen their understanding of elementary NMR theory or theoretical tools” – Magnetic Resonance in Chemistry

Download or read book Organic Spectroscopy written by Lal Dhar Singh Yadav and published by Springer Science & Business Media. This book was released on 2013-08-30 with total page 334 pages. Available in PDF, EPUB and Kindle. Book excerpt: Organic Spectroscopy presents the derivation of structural information from UV, IR, Raman, 1H NMR, 13C NMR, Mass and ESR spectral data in such a way that stimulates interest of students and researchers alike. The application of spectroscopy for structure determination and analysis has seen phenomenal growth and is now an integral part of Organic Chemistry courses. This book provides: -A logical, comprehensive, lucid and accurate presentation, thus making it easy to understand even through self-study; -Theoretical aspects of spectral techniques necessary for the interpretation of spectra; -Salient features of instrumentation involved in spectroscopic methods; -Useful spectral data in the form of tables, charts and figures; -Examples of spectra to familiarize the reader; -Many varied problems to help build competence ad confidence; -A separate chapter on ‘spectroscopic solutions of structural problems’ to emphasize the utility of spectroscopy. Organic Spectroscopy is an invaluable reference for the interpretation of various spectra. It can be used as a basic text for undergraduate and postgraduate students of spectroscopy as well as a practical resource by research chemists. The book will be of interest to chemists and analysts in academia and industry, especially those engaged in the synthesis and analysis of organic compounds including drugs, drug intermediates, agrochemicals, polymers and dyes.

Download or read book Stereochemical Analysis of Alicyclic Compounds by C 13 NMR Spectroscopy written by J. A. Whitesell and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 213 pages. Available in PDF, EPUB and Kindle. Book excerpt: Through numerous conversations with other synthetic chemists it became apparent that the great power of carbon nuclear magnetic resonance was being significantly underutilized. In our own work we have found that 13C spectroscopy is a more powerful tool than IH NMR spectroscopy, especially for probing subtle stereochemical questions in complicated systems. This is especially true in five membered ring compounds where IH NMR is at a particular disadvantage. The two techniques can be used independently to solve the same question-that of stereochemistry - but they do so in different ways. Advantage can be taken in IH NMR of a relatively consistent relationship between stereochemical orientation and coupling constants between vicinal protons, while in 13C NMR it is the correlation between spatial relationships of non-hydrogen, y substituents and their effect on chemical shift that can be used to assign stereochemistry. It was also clear that the use of 13C NMR required a different approach to problem solving than that typically used with IH NMR. While the latter technique could be employed with a very general approach (e.g., the Karplus equation), 13C NMR would, at least for the immediate future, require a relatively extensive set of model systems from which the consequences of stereochemical changes could be derived for any given carbon framework.

Download or read book 31P and 13C NMR of Transition Metal Phosphine Complexes written by Paul S. Pregosin and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt: For almost a quarter of a century the words "nuclear magnetic reso nance" were synonymous with proton I,leasurements. During this period the literature abounded with a seemingly infinite variety of 1H NHR studies concerned primarily with carbon chemistry. Occasionally a "novel" nucleus was studied and, even in those early days, the poten- 13 14 31 19 tial offered by C, N, P and F was clearly recognized. Despite the allure, the technical difficulties involved in measuring some of these nuclei were far from trivial. Small magnetic moments and low natural abundance in combination with spin-spin coupling from other nuclei, mostly protons, resulted in a signal-to-noise problem whose severity effectively excluded the study of metal complexes with unfa vorable solubility characteristics. The first important breakthrough came with the advent of broad band 1H-decoupling. For example, the featureless broad 31p resonance associated with the commonly used ligand triphenyl phosphine is converted to a sharp, more readily ob served singlet when wide-band decoupling is employed (see Fig. 1). Despite this improvement investigation of more interesting molecules, such as catalytically active complexes was forced to await the devel opment of Fourier Transform methods since only with relatively rapid signal averaging methods could sufficient signal-to-noise ratios be achieved.

Download or read book NMR in Chemistry written by William Kemp and published by Free Press. This book was released on 1988 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Proton and Carbon 13 NMR Spectroscopy written by Raymond John Abraham and published by John Wiley & Sons. This book was released on 1978 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Essential Practical NMR for Organic Chemistry written by S. A. Richards and published by John Wiley & Sons. This book was released on 2010-12-07 with total page 345 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes the use of NMR spectroscopy for dealing with problems of small organic molecule structural elucidation. It features a significant amount of vital chemical shift and coupling information but more importantly, it presents sound principles for the selection of the techniques relevant to the solving of particular types of problem, whilst stressing the importance of extracting the maximum available information from the simple 1-D proton experiment and of using this to plan subsequent experiments. Proton NMR is covered in detail, with a description of the fundamentals of the technique, the instrumentation and the data that it provides before going on to discuss optimal solvent selection and sample preparation. This is followed by a detailed study of each of the important classes of protons, breaking the spectrum up into regions (exchangeables, aromatics, heterocyclics, alkenes etc.). This is followed by consideration of the phenomena that we know can leave chemists struggling; chiral centres, restricted rotation, anisotropy, accidental equivalence, non-first-order spectra etc. Having explained the potential pitfalls that await the unwary, the book then goes on to devote chapters to the chemical techniques and the most useful instrumental ones that can be employed to combat them. A discussion is then presented on carbon-13 NMR, detailing its pros and cons and showing how it can be used in conjunction with proton NMR via the pivotal 2-D techniques (HSQC and HMBC) to yield vital structural information. Some of the more specialist techniques available are then discussed, i.e. flow NMR, solvent suppression, Magic Angle Spinning, etc. Other important nuclei are then discussed and useful data supplied. This is followed by a discussion of the neglected use of NMR as a tool for quantification and new techniques for this explained. The book then considers the safety aspects of NMR spectroscopy, reviewing NMR software for spectral prediction and data handling and concludes with a set of worked Q&As.

Download or read book NMR Spectroscopy Explained written by Neil E. Jacobsen and published by John Wiley & Sons. This book was released on 2007-09-10 with total page 640 pages. Available in PDF, EPUB and Kindle. Book excerpt: NMR Spectroscopy Explained : Simplified Theory, Applications and Examples for Organic Chemistry and Structural Biology provides a fresh, practical guide to NMR for both students and practitioners, in a clearly written and non-mathematical format. It gives the reader an intermediate level theoretical basis for understanding laboratory applications, developing concepts gradually within the context of examples and useful experiments. Introduces students to modern NMR as applied to analysis of organic compounds. Presents material in a clear, conversational style that is appealing to students. Contains comprehensive coverage of how NMR experiments actually work. Combines basic ideas with practical implementation of the spectrometer. Provides an intermediate level theoretical basis for understanding laboratory experiments. Develops concepts gradually within the context of examples and useful experiments. Introduces the product operator formalism after introducing the simpler (but limited) vector model.