Hydrogen Bonding In Organic Synthesis

This first comprehensive overview of the rapidly growing field emphasizes the use of hydrogen bonding as a tool for organic synthesis, especially catalysis. As such, it covers such topics as enzyme chemistry, organocatalysis and total synthesis, all unified by the unique advantages of hydrogen bonding in the construction of complex molecules from simple precursors. Providing everything you need to know, this is a definite must for every synthetic chemist in academia and industry.

Research Paper (undergraduate) from the year 2019 in the subject Chemistry - Bio-chemistry, grade: 1,0, University of Cologne, language: English, abstract: This work is about the non-covalent catalysis and concentrates on the hydrogen-bond catalysis. Nowadays it is common to use catalysis in organic synthesis. It can help in orienting the substrates, lowering barriers to reaction and accelerating the rates of reaction. In addition to metal-ligand systems and biocatalysts, there is another class of catalysts, the organocatalysts which are free of any metals, like many enzymes. The organocatalysts often consist of chiral compounds. The output materials are easy to find in the nature. How these catalysts accelerate the reaction rates is a central question in organic synthesis. It is important to distinguish the interactions with the organic substrates between covalent and non-covalent bonds. The activation of a carbonyl compound by conversion into an enamine or into an iminium ion belongs to the covalent catalysis, while to increase the electrophilicity of a carbonyl group by formation of hydrogen bondings is a typical example for non-covalent organocatalysis. Thus, the acceleration and the control of the reaction rates depend on formation of hydrogen bonds for non-covalent organocatalysis. It is possible to catalyse two hydrogen bonds which occur in dual hydrogen bonding donors.

This monograph describes the behavior of molecules confined to small spaces. The small spaces are created by the self-assembly of modules into hollow capsular structures through hydrogen bonding; capsules assembled by metal/ligand binding or other forces are not included. Topics discussed include how assembly of capsules occurs, how molecules get in and out of the capsules, new spatial arrangements (stereochemistry) created in the capsules, and the altered shapes, interactions and reactivities of molecules held inside the small spaces. The descriptions emphasize molecular recognition phenomena and the perspective is that of physical organic chemistry.The book is the first monograph to treat reversible molecular encapsulation. More than 20 university and institute groups worldwide engage in this research, which represents the leading edge of activity in molecular recognition and the physical organic chemistry of confined molecules.

The weak or non-conventional hydrogen bond has been subject of intense scrutiny over recent years in several fields, in particular in structural chemistry, structural biology, and also in the pharmaceutical sciences. There is today a large body of experimental and theoretical evidenceconfirming that hydrogen bonds like C-H...O, N-H...pi, C-H...pi and even bonds like O-H...metal play distinctive roles in molecular recognition, guiding molecular association, and in determining molecular and supramolecular architectures. The relevant compound classes include organometalliccomplexes, organic and bio-organic systems, and also DNA and proteins. The book provides a comprehensive assessment of this interaction type, and is of interest to all those interested in structural and supramolecular science, including fields as crystal engineering and drug design.

This book covers the advances in the studies of hydrogen-bonding-driven supramolecular systems made over the past decade. It is divided into four parts, with the first introducing the basics of hydrogen bonding and important hydrogen bonding patterns in solution as well as in the solid state. The second part covers molecular recognition and supramolecular structures driven by hydrogen bonding. The third part introduces the formation of hollow and giant macrocycles directed by hydrogen bonding, while the last part summarizes hydrogen bonded supramolecular polymers. This book is designed to bring together in a single volume the many important aspects of hydrogen bonding supramolecular chemistry and will be a valuable resource for graduates and researchers working in supramolecular and related sciences. Zhan-Ting Li, PhD, is a Professor of Organic Chemistry at the Department of Chemistry, Fudan University, China. Li-Zhu Wu, PhD, is a Professor of Organic Chemistry at the Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, China.

Hydrogen bonded systems play an important role in all aspects of science but particularly chemistry and biology. Notably, the helical structure of DNA is heavily reliant on the hydrogens bonds between the DNA base pairs. Although the area of hydrogen bonding is one that is well established, our understanding has continued to develop as the power of both computational and experimental techniques has improved. Understanding Hydrogen Bonds presents an up-to-date overview of our theoretical and experimental understanding of the hydrogen bond. Well-established and novel approaches are discussed, including quantum theory of ‘atoms in molecules’ (QTAIM); the electron localization function (ELF) method and Car–Parinnello molecular dynamics; the natural bond orbital (NBO) approach; and X-ray and neutron diffraction and spectroscopy. The mechanism of hydrogen bond formation is described and comparisons are made between hydrogen bonds and other types of interaction. The author also takes a look at new types of interaction that may be classified as hydrogen bonds with a focus on those with multicentre proton acceptors or with multicentre proton donors. Understanding Hydrogen Bonds is a valuable reference for experimentalists and theoreticians interested in updating their understanding of the types of hydrogen bonds, their role in chemistry and biology, and how they can be studied.

This book is an up-to-date text covering topics in utilizing hydrogen bonding for constructing functional architectures and supramolecular materials. The first chapter addresses the control of photo-induced electron and energy transfer. The second chapter summarizes the formation of nano-porous materials. The following two chapters introduce self-assembled gels, many of which exhibit unique functions. Other chapters cover the advances in supramolecular liquid crystals and the versatility of hydrogen bonding in tuning/improving the properties and performance of materials. This book is designed to bring together in a single volume the most important and active fields of hydrogen bonding strategy for designing supramolecular materials. The book will be a valuable resource for graduates and researchers working in the fields of supramolecular chemistry and materials sciences. Zhan-Ting Li, PhD, is a Professor of Organic Chemistry at the Department of Chemistry, Fudan University, China Li-Zhu Wu, PhD, is a Professor of Organic Chemistry at the Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, China

Greener than conventional methods, C-H activation methods have flourished during the last decade and become especially attractive to organic chemists. Edited by a practioner in this rapidly developing field, C-H Bond Activation in Organic Synthesis provides an overview of this exciting playground of chemistry. The book summarizes the state of the a

Organocatalysis has recently attracted enormous attention as green and sustainable catalysis. It was realized as a fundamental field providing wide families of catalysts for important organic transformations. It will certainly develop in the future. Given the diversity of accessible transformations, metal-catalyzed reactions have become major tools in organic synthesis that will undoubtedly continue to have an important impact in the future. Alternatively, over the last years, a metal-free approach such as organocatalysis has reached a level of faithfulness, allowing researchers to discover new catalytic systems based on engagement of new or early-prepared organic molecules as organocatalysts. Organocatalysis meets green chemistry principles, especially the reduction of toxicity and chemical accidents, the biodegradability, and the use of benign and friendlier reaction media and conditions.