Download or read book The Chemistry of Rotational Isomers written by Michinori Oki and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 261 pages. Available in PDF, EPUB and Kindle. Book excerpt: Rotation about the Carbon-Carbon single bond is generally regarded to be unrestricted. About 50 years ago, rotational isomers were found to exhibit optical activity: substituted biphenyl derivatives. However, the author has investigated other classes of compounds that have stable rotational isomers at room temperature. These compounds can serve as models for studying very weak intermolecular interactions, that are difficult to observe. Even diastereotopic groups show different chemical reactivity. From the contents: The "Free Rotation Concept" - Rotamer Populations - Barriers to Rotation - Reactivity of Rotational Isomers.
Download or read book The Chemistry of Rotational Isomers written by Michinori Ōki and published by . This book was released on 1993 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Introduction to Stereochemistry written by Torsten Schmiermund and published by Springer Nature. This book was released on 2021-06-07 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt: Conformal, diastereomers, rotamers, tautomers, anomers: The multitude of terms used in stereochemistry quickly makes this subfield of chemistry confusing. In addition, there are different nomenclatures and different forms of representation (Fischer projection, Haworth ring formula, Newman projection). This essential deals with basic static stereochemistry and gives an overview of the different isomeric forms and nomenclatures. It is thus both a help and a reference book. This Springer essential is a translation of the original German 1st edition essentials, Einführung in die Stereochemie by Torsten Schmiermund, published by Springer Fachmedien Wiesbaden GmbH, part of Springer Nature in 2019. The translation was done with the help of artificial intelligence (machine translation by the service DeepL.com). A subsequent human revision was done primarily in terms of content, so that the book will read stylistically differently from a conventional translation. Springer Nature works continuously to further the development of tools for the production of books and on the related technologies to support the authors.
Download or read book Structure of Molecules and Internal Rotation written by San-Ichiro Mizushima and published by Academic Press. This book was released on 2013-10-22 with total page 255 pages. Available in PDF, EPUB and Kindle. Book excerpt: Structure of Molecules and Internal Rotation reviews early studies on dihalogenoethanes. This book is organized into two parts encompassing 8 chapters that evaluate the Raman effect in ethane derivatives, the energy difference between rotational isomers, and the infrared absorption of ethane derivatives. Some of the topics covered in the book are the potential barrier to internal rotation; nature of the hindering potential; entropy difference between the rotational isomers; internal rotation in butane, pentane, and hexane; and internal rotation in long chain n-paraffins. Other chapters deal with the configuration of a polypeptide chain, as well as the sum rule and the product rule for rotational isomers. The normal vibrations of the 1,2-dihalogenoethanes are presented. The last chapters are devoted to the examination of the Raman effect, dielectric constant, and electron diffraction. The book can provide useful information to chemists, physicists, students, and researchers.
Download or read book Rotational Isomerism of 1 2 dichloroethane and 1 2 dibromoethane written by Yu. A. Pentin and published by . This book was released on 1953 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Structure of Molecules and Internal Rotation written by San-Ichiro Mizushima and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Structure of Molecules and Internal Rotation reviews early studies on dihalogenoethanes. This book is organized into two parts encompassing 8 chapters that evaluate the Raman effect in ethane derivatives, the energy difference between rotational isomers, and the infrared absorption of ethane derivatives. Some of the topics covered in the book are the potential barrier to internal rotation; nature of the hindering potential; entropy difference between the rotational isomers; internal rotation in butane, pentane, and hexane; and internal rotation in long chain n-paraffins. Other chapters deal wi ...
Download or read book Basic Principles of Organic Chemistry written by John D. Roberts and published by . This book was released on 1965 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Rotational Isomers of Mo VI Alkylidene Complexes and Polymer Structure written by John Henry Oskam and published by . This book was released on 1993 with total page 394 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Internal Rotation in Molecules written by Mavis Redshaw and published by John Wiley & Sons. This book was released on 1974 with total page 634 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Rotational Spectra and Molecular Structure written by James E. Wollrab and published by . This book was released on 1967 with total page 498 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Optical Activity and Chemical Composition written by Hans Landolt and published by . This book was released on 1899 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Conformational Analysis written by Ernest Ludwig Eliel and published by . This book was released on 1967 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Rotational Spectroscopy of Diatomic Molecules written by John M. Brown and published by Cambridge University Press. This book was released on 2003-04-10 with total page 1074 pages. Available in PDF, EPUB and Kindle. Book excerpt: The definitive text on the rotational spectroscopy of diatomic molecules.
Download or read book Chemistry written by Bruce Averill and published by . This book was released on 2007 with total page 1233 pages. Available in PDF, EPUB and Kindle. Book excerpt: Emphasises on contemporary applications and an intuitive problem-solving approach that helps students discover the exciting potential of chemical science. This book incorporates fresh applications from the three major areas of modern research: materials, environmental chemistry, and biological science.
Download or read book Structures and Conformations of Non Rigid Molecules written by J. Laane and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 640 pages. Available in PDF, EPUB and Kindle. Book excerpt: From the beginnings of modern chemistry, molecular structure has been a lively area of research and speculation. For more than half a century spectroscopy and other methods have been available to characterize the structures and shapes of molecules, particularly those that are rigid. However, most molecules are at least to some degree non-rigid and this non-rigidity plays an important role in such diverse areas as biological activity, energy transfer, and chemical reactivity. In addition, the large-amplitude vibrations present in non-rigid molecules give rise to unusual low-energy vibrational level patterns which have a dramatic effect on the thermodynamic properties of these systems. Only in recent years has a coherent picture of the energetics and dynamics of the conformational changes inherent in non-rigid (and semi-rigid) molecules begun to emerge. Advances have been made in a number of different experimental areas: vibrational (infrared and Raman) spectroscopy, rotational (microwave) spectroscopy, electron diffraction, and, most recently, laser techniques probing both the ground and excited electronic states. Theoretically, the proliferation of powerful computers coupled with scientific insight has allowed both empirical and ab initio methods to increase our understanding of the forces responsible for the structures and energies of non-rigid systems. The development of theory (group theoretical methods and potential energy surfaces) to understand the unique characteristics of the spectra of these floppy molecules has also been necessary to reach our present level of understanding. The thirty chapters in this volume contributed by the key speakers at the Workshop are divided over the various areas. Both vibrational and rotational spectroscopy have been effective at determining the potential energy surfaces for non-rigid molecules, often in a complementary manner. Recent laser fluorescence work has extended these types of studies to electronic excited states. Electronic diffraction methods provide radial distribution functions from which both molecular structures and compositions of conformational mixtures can be found. Ab initio calculations have progressed substantially over the past few years, and, when carried out at a sufficiently high level, can accurately reproduce (or predict ahead of time) experimental findings. Much of the controversy of the ARW related to the question of when an ab initio is reliable. Since the computer programs are readily available, many poor calculations have been carried out. However, excellent results can be obtained from computations when properly done. A similar situation exists for experimental analyses. The complexities of non-rigid molecules are many, but major strides have been taken to understand their structures and conformational processes.
Download or read book Principles of Asymmetric Synthesis written by R.E. Gawley and published by Elsevier. This book was released on 1996-11-21 with total page 394 pages. Available in PDF, EPUB and Kindle. Book excerpt: The world is chiral. Most of the molecules in it are chiral, and asymmetric synthesis is an important means by which enantiopure chiral molecules may be obtained for study and sale. Using examples from the literature of asymmetric synthesis (more than 1300 references), the aim of this book is to present a detailed analysis of the factors that govern stereoselectivity in organic reactions. It is important to note that the references were each individually checked by the authors to verify relevance to the topics under discussion. The study of stereoselectivity has evolved from issues of diastereoselectivity, through auxiliary-based methods for the synthesis of enantiomerically pure compounds (diastereoselectivity followed by separation and auxiliary cleavage), to asymmetric catalysis. In the latter instance, enantiomers (not diastereomers) are the products, and highly selective reactions and modern purification techniques allow preparation - in a single step - of chiral substances in 99% ee for many reaction types. After an explanation of the basic physical-organic principles of stereoselectivity, the authors provide a detailed, annotated glossary of stereochemical terms. A chapter on "Analytical Methods" provides a critical overview of the most common methods for analysis of stereoisomers. The authors then follow the 'tried-and-true' format of grouping the material by reaction type. Thus, there are four chapters on carbon-carbon bond forming reactions (enolate alkylations, organometal additions to carbonyls, aldol and Michael reactions, and cycloadditions and rearrangements), one chapter on reductions and hydroborations (carbon-hydrogen bond forming reactions), and one on oxidations (carbon-oxygen and carbon-nitrogen bond forming reactions). Leading references are provided to natural product synthesis that have been accomplished using a given reaction as a key step. In addition to tables of examples that show high selectivity, a transition state analysis is presented to explain - to the current level of understanding - the stereoselectivity of each reaction. In one case (Cram's rule) the evolution of the current theory is detailed from its first tentative (1952) postulate to the current Felkin-Anh-Heathcock formalism. For other reactions, only the currently accepted rationale is presented. Examination of these rationales also exposes the weaknesses of current theories, in that they cannot always explain the experimental observations. These shortcomings provide a challenge for future mechanistic investigations.
Download or read book The Rotational Isomers of 1 1 2 2 Tetrachloroethane written by Jen Shu Hsieh and published by . This book was released on 1964 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt:
