New Entries To Asymmetric Anion Binding Catalysis With Chiral Oligotriazoles

Explores the potential of new types of anion-binding catalysts to solve challenging synthetic problems Anion-Binding Catalysis introduces readers to the use of anion-binding processes in catalytic chemical activation, exploring how this approach can contribute to the future design of novel synthetic transformations. Featuring contributions by world-renowned scientists in the field, this authoritative volume describes the structure, properties, and catalytic applications of anions as well as synthetic applications and practical analytical methods. In-depth chapters are organized by type of catalyst rather than reaction type, providing readers with an accessible overview of the existing classes of effective catalysts. The authors discuss the use of halogens as counteranions, the combination of (thio)urea and squaramide-based anion-binding with other types of organocatalysis, anion-binding catalysis by pnictogen and tetrel bonding, nucleophilic co-catalysis, anion-binding catalysis by pnictogen and tetrel bonding, and more. Helping readers appreciate and evaluate the potential of anion-binding catalysis, this timely book: Illustrates the historical development, activation mode, and importance of anion-binding in chemical catalysis Explains the analytic methods used to determine the anion-binding affinity of the catalysts Describes catalytic and synthetic applications of common NH- and OH-based hydrogen-donor catalysts as well as C-H triazole/triazolium catalysts Covers amino-catalysis involving enamine, dienamine, or iminium activation approaches Discusses new trends in the field of anion-binding catalysis, such as the combination of anion-binding with other types of catalysis Presenting the current state of the field as well as the synthetic potential of anion-binding catalysis in future, Anion-Binding Catalysis is essential reading for researchers in both academia and industry involved in organic synthesis, homogeneous catalysis, and pharmaceutical chemistry.

Asymmetric Organocatalysis Comprehensive resource on the latest and most important developments in the highly vivid field of asymmetric organocatalysis The book provides a comprehensive overview of the most important advancements in the field of asymmetric organocatalysis that have occurred within the last decade. It presents valuable examples of newly developed synthetic methodologies based on various organocatalytic activation modes. Special emphasis is given to strategies where organocatalysis is expanding its potential by pushing the boundaries and founding new synergistic interactions with other fields of synthetic chemistry, such as metal catalysis, photocatalysis, and biocatalysis. The application of different concepts (such as vinylogy, dearomatization, or cascade reactivity), resulting in the development of new functionalization strategies, is also discussed. Sample topics covered within the book include: New developments in enantioselective Brønsted acid catalysis with strong hydrogen-bond donors Asymmetric phase-transfer catalysis, from classical applications to new concepts Halogen-bonding organocatalysis Asymmetric electrochemical organocatalysis and synergistic organo-organocatalysis Immobilized organocatalysts for enantioselective continuous flow processes Mechanochemistry and high-pressure techniques in asymmetric organocatalysis Useful tools in elucidation of organocatalytic reaction mechanisms With an overall focus on new reactions and catalysts, this two-volume work is an indispensable source for everyone working in the field of asymmetric organocatalysis.

The dual catalytic approach in asymmetric catalysis has gained considerable attention in recent times. Many otherwise inefficient and unattainable chemical processes can be accomplished by this approach. Outlined within this dissertation are recent efforts in improving the overall efficiency of this process as well as expanding this method involving nucleophilic/anion-binding catalysis to the kinetic resolution of allylic amines and 1,2-diamines. An efficient catalytic system has been identified through targeted structural modifications of both the achiral nucleophilic catalyst and the chiral anion-binding co-catalyst. This has resulted in increased selectivities while simultaneously allowing for significantly reduced catalyst loadings. Based on the mechanistic insight into the anion binding approach for the kinetic resolution of amines, we established that there was a 1:1 catalyst to benzoate anion binding ratio. Cooperative approaches in which Brønsted acids act in concert with other Brønsted acids or (thio) urea co-catalysts have gained significance. This study describes the synthesis of a new class of chiral conjugate-base-stabilized Brønsted acid catalysts and a new concept for cooperative hydrogen bonding/ Brønsted acid catalysis. These chiral Brønsted acids contain a carboxylic acid group which is connected via an appropriate linker to an anion receptor moiety such as a thiourea. Substrate protonation by the catalyst results in the association of the conjugate base with the anion recognition site, resulting in the formation of a rigid catalyst/substrate ion pair. We were able to successfully apply this concept to the catalytic enantioselective Povarov and Pictet-Spengler reactions.

A compilation of recent advances and applications in asymmetric catalysis The field of asymmetric catalysis has grown rapidly and plays a key role in drug discovery and pharmaceuticals. New Frontiers in Asymmetric Catalysis gives readers a fundamental understanding of the concepts and applications of asymmetric catalysis reactions and discusses the latest developments and findings. With contributions from preeminent scientists in their respective fields, it covers: * "Rational" ligand design, which is critically dependent on the reaction type (reduction, oxidation, and C-C bond formation) * Recent findings on activation of C-H bonds, C-C bonds, and small molecules (C=O, HCN, RN=C, and CO2) and the latest developments on C-C bond reorganization, such as metathesis * Advances in "chirally economical" non-linear phenomena, racemic catalysis, and autocatalysis * Some of the recent discoveries that have led to a renaissance in the field of organocatalysis, including the development of chiral Brönstead acids and Lewis acidic metals bearing the conjugate base of the Brönstead acids as the ligands and the chiral bi-functional acid/base catalysts The book ends with a thought-provoking perspective on the future of asymmetric catalysis that addresses both the challenges and the unlimited potential in this burgeoning field. This is an authoritative, up-to-date reference for organic chemists in academia, government, and industries, including pharmaceuticals, biotech, fine chemicals, polymers, and agriculture. It is also an excellent textbook for graduate students studying advanced organic chemistry or chemical synthesis.

Supramolecular Catalysis Provides a timely and detailed overview of the expanding field of supramolecular catalysis The subdiscpline of supramolecular catalysis has expanded in recent years, benefiting from the development of homogeneous catalysis and supramolecular chemistry. Supramolecular catalysis allows chemists to design custom-tailored metal and organic catalysts by devising non-covalent interactions between the various components of the reaction. Edited by two world-renowned researchers, Supramolecular Catalysis: New Directions and Developments summarizes the most significant developments in the dynamic, interdisciplinary field. Contributions from an international panel of more than forty experts address a broad range of topics covering both organic and metal catalysts, including emergent catalysis by self-replicating molecules, switchable catalysis using allosteric effects, supramolecular helical catalysts, and transition metal catalysis in confined spaces. This authoritative and up-to-date volume: Covers ligand-ligand interactions, assembled multi-component catalysts, ligand-substrate interactions, and supramolecular organocatalysis and non-classical interactions Presents recent work on supramolecular catalysis in water, supramolecular allosteric catalysis, and catalysis promoted by discrete cages, capsules, and other confined environments Highlights current research trends and discusses the future of supramolecular catalysis Includes full references and numerous figures, tables, and color illustrations Supramolecular Catalysis: New Directions and Developments is essential reading for catalytic chemists, complex chemists, biochemists, polymer chemists, spectroscopists, and chemists working with organometallics.

The second supplement to the three volume reference work Comprehensive Asymmetric Catalysis critically reviews new developments to the hottest topics in the field written by recognised experts. Seven chapters which are already in the major reference work have been supplemented and additionally a new chapter on Aminohydroxylation of Carbon-Carbon Double Bonds has been included. Thus, the state of the art in this area is now re-established. Together with the basic three volume book set and Supplement 1 it is not only the principal reference source for synthetic organic chemists, but also for all scientific researchers who use chiral compounds in their work (for example, in biochemical investigations and molecular medicine) as well as for pharmaceutical chemists and other industrial researchers who prepare chiral compounds.

Advances in Organic Synthesis is a book series devoted to the latest advances in synthetic approaches towards challenging structures. The series presents comprehensive reviews written by eminent authorities on different synthetic approaches to selected target molecules and new methods developed to achieve specific synthetic transformations or optimal product yields. Advances in Organic Synthesis is essential for all organic chemists in academia and the industry who wish to keep abreast of rapid and important developments in the field. This volume presents the following reviews: o Recent Progress on Asymmetric Synthesis of Chiral Flavanones, Chromanones, and Chromenes o Supramolecular Chemistry of Modified Amino Acids and Short Peptides o The Use of Nanocatalysts in the Synthesis of Heterocycles: A Contemporary Approach o Synthesis and Applications of 1,2,3-Triazoles o Ring C–H Functionalization of Aromatic N-Oxides.

A comprehensive overview of synthetic strategies for nonaromatic nitrogen heterocycles Nitrogen heterocycles are extremely widely distributed in nature, as well as in synthetic substances found in pharmaceuticals, agrochemicals, and materials chemistry. With new structures and medicines that include these structures emerging yearly, and a vast new journal literature to describe them, anyone who wants to be effective in R&D needs to easily access a synthesis of the latest research. This state-of-the-art survey explores recent developments in the most widely used reactions, as well as completely new ones. Highlights the major modern synthetic methods known to obtain nonaromatic nitrogen heterocycles, and their practical applications Topics include enantioselective synthesis and catalysis, photocatalysis, biocatalysis, microwave-assisted synthesis, reactions of oximes and nitrones, and ionic liquids Discusses how to synthesize rings of specific sizes Covers sustainable synthetic approaches for obtaining salts Whether you are using nonaromatic nitrogen compounds as an academic researcher, a synthetic chemist in industry, or an advanced student, this book is an essential, up-to-date resource to support your work.