Download or read book Asymmetric Synthesis Of 3 3 disubstituted Oxindoles written by Dalpozzo Renato and published by World Scientific. This book was released on 2019-09-11 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt: Indole derivatives are the most common heterocycle compounds present in nature, for this reason, they have been referred to as 'privileged structures'. In fact, many approved drugs — and natural products — belong to this family. Among indole derivatives, oxindoles have a structural complexity, which have stimulated generations of synthetic chemists to design strategies for assembling these structures, and their enantioselective synthesis is still growing.This book proposes to describe the known enantioselective syntheses of oxindole derivatives. It is divided in six chapters each referring to a specific class of asymmetric oxindole derivatives. After the introduction, Chapter 2 describes all-carbon spirooxindoles; Chapter 3, open chain 3,3-dialkyloxindoles; Chapter 4, 3-substituted-3-aminooxindoles; Chapter 5, 3-substituted-3-hydroxyoxindoles; Chapter 6, 3-hetero-3-substituted oxindoles. It will be a useful tool for synthetic chemists, who assemble total synthesis of natural products, as well as for drug discovery chemists either in academic or in industry R&S laboratories.

Download or read book Asymmetric Synthesis of 3 3 disubstituted Oxindoles written by Renato Dalpozzo and published by . This book was released on 2019 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Indole derivatives are the most common heterocycle compounds present in nature, for this reason, they have been referred to as "privileged structures". In fact, many approved drugs - and natural products - belong to this family. Among indole derivatives, oxindoles have a structural complexity, which have stimulated generations of synthetic chemists to design strategies for assembling these structures, and their enantioselective synthesis is still growing. This book proposes to describe the known enantioselective syntheses of oxindole derivatives. It is divided in six chapters each referring to a specific class of asymmetric oxindole derivatives. After the introduction, Chapter 2 describes all-carbon spirooxindoles; Chapter 3, open chain 3,3-dialkyloxindoles; Chapter 4, 3-substituted-3-aminooxindoles; Chapter 5, 3-substituted-3-hydroxyoxindoles; Chapter 6, 3-hetero-3-substituted oxindoles. It will be a useful tool for synthetic chemists, who assemble total synthesis of natural products, as well as for drug discovery chemists either in academic or in industry R&S laboratories."--

Download or read book Studies in Natural Products Chemistry written by Albert Moyano and published by Elsevier Inc. Chapters. This book was released on 2013-06-25 with total page 83 pages. Available in PDF, EPUB and Kindle. Book excerpt: Functional diversity and molecular architecture in biologically active oxindoles. Transition metal-catalyzed intramolecular Heck reactions and amide alpha-arylations. Asymmetric rearrangements of O-carbonylated oxindoles and related processes. Amination, hydroxylation, and halogenation reactions of 3-substituted oxindoles. Conjugate addition and alkylation reactions of 3-substituted oxindoles. Asymmetric aldol and Mannich reactions of isatins. Michael additions to isatin-derived electron-deficient alkynes. Nucleophilic substitution reactions of functionalized 3-substituted oxindoles. Enantioselective construction of spirooxindoles by cycloaddition, annulation, and cascade cyclization reactions of methyleneindolinone derivatives. The 3,3-disubstituted-2-oxindole moiety is present in many chiral alkaloids that exhibit interesting biological activities. The enantioselective synthesis of chiral oxindole derivatives has been mainly achieved by asymmetric catalytic methods. In this review we highlight the most important catalytic methods relevant to the synthesis of chiral, non-spirocyclic 3,3-disubstituted oxindoles.

Download or read book Catalytic Enantioselective Synthesis of Aryl Substituted 3 hydroxy 2 oxindoles and 3 3 disubstituted 2 oxindoles written by Aziza Hatice Sahin and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In Chapter One, a catalytic enantioselective method for the synthesis of 3- hydroxy-2-oxindoles is described. 3-Hydroxy-2-oxindoles were synthesized by a nucleophilic addition of electron-rich arenes and aromatic heterocycles to substituted indole-2,3-diones (isatins) catalyzed by scandium(III) and indium(III)-inda-pybox complexes. The use of a bulky chiral ligand hindered the formation of the achiral 3,3-diaryl-2-oxindole side product. Substituted 3-hydroxy-2-oxindoles were formed in high yield and high enantioselectivity (up to 99% ee). In Chapter Two, a method for the synthesis of chiral 3,3-disubstituted-2-oxindoles from a nucleophilic substitution at the stereocenter of a substituted 3-hydroxy-2-oxindole is described. This SN̳1-like process is catalyzed by a Lewis or a Brønsted acid, which eliminates water to form an indolenium ion intermediate. Chiral BINOL-derived phosphoric acids and phosphoramides are promising catalysts for an asymmetric process, as the conjugate base can act as a counteranion that coordinates to the carbocation intermediate to direct an asymmetric nucleophilic addition. Catalyst and solvent effects have been investigated with yields ranging from 68-97%. Preliminary enantioselectivity has been observed and further optimization is underway.

Download or read book Studies in Natural Products Chemistry written by and published by Newnes. This book was released on 2013-06-25 with total page 533 pages. Available in PDF, EPUB and Kindle. Book excerpt: Natural products in the plant and animal kingdom offer a huge diversity of chemical structures that are the result of biosynthetic processes that have been modulated over the millennia through genetic effects. With the rapid developments in spectroscopic techniques and accompanying advances in high-throughput screening techniques, it has become possible to isolate and then determine the structures and biological activity of natural products rapidly, thus opening up exciting new opportunities in the field of new drug development to the pharmaceutical industry. The series also covers the synthesis or testing and recording of the medicinal properties of natural products. - Describes the chemistry of bioactive natural products - Contains contributions by leading authorities in the field - A valuable resource for natural products and medicinal chemistry

Download or read book Chiral Lewis Acid and Organocatalytic Methods for the Asymmetric Synthesis and Functionalization of 3 3 oxindoles and 3 3 spirocyclic Oxindoles written by Joseph Jesse Badillo and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The development of regio- and stereoselective methods for the synthesis of oxindoles and spirocyclic oxindoles is important due to the prevalence of these structures in natural products and medicinal agents. This dissertation describes both Lewis acid and organocatalytic strategies for the regio-, diastereo-, and enantioselective synthesis of several classes of 3,3'-oxindoles and 3,3'-spirooxindoles. These strategies are applied to several synthetic transformations including allylsilane annulations, Friedel-Crafts alkylations, and Pictet-Spengler reactions. Chapter one describes an overview of recent methods for the enantioselective synthesis of oxindoles and spirooxindoles with a particular focus on scaffolds relevant to drug discovery. This overview is organized by type of catalyst and strategy in order to compare traditional organometallic and Lewis acid methods with recent organocatalytic methods. This chapter also features a section on multicomponent and cascade reaction strategies. Chapter two describes the development of synthetic methodology using titanium(IV)-catalysis for the selective synthesis of two new classes of spirocyclic oxindoles. In the first section, I present a highly regio- and diastereoselective method for the synthesis of spiro[3,3'oxindoleoxazolines] upon addition of 5-methoxy-2-oxazoles to isatins. In the second section, I present a method for the addition of 5-methoxy-2-aryloxazoles to [alpha],[beta]-unsaturated alkylidene oxindoles to provide access to spiro[3,3'oxindole-1-pyrrolines] with excellent yields and diastereoselectivities. This methodology is also effective for the diastereoselective synthesis of 1-pyrrolines derived from coumarins and simple malonates. Chapter three describes the condensation cyclization between isatins and 5-methoxytryptamine catalyzed by chiral phosphoric acids to provide spirooxindole tetrahydro-[beta]-carboline products in excellent yields and enantioselectivity. A comparison of catalysts provides insight for the reaction scope and factors responsible for efficient catalytic activity and selectivity in these Pictet-Spengler type spirocyclization reactions. In addition I show that chiral phosphoric acids with different 3,3'-substitution on the binaphthyl system and opposite axial chirality afford the spiroindolone product with the same absolute configuration. Chapter four describes a strategy for the efficient two-step synthesis of triazole derivatives of oxindoles and spirooxindoles. Using a common set of N-propargylated isatins, a series of mechanistically distinct stereoselective reactions with different combinations of nucleophiles and catalysts provides access to diverse hydroxy-oxindoles, spiroindolones, and spirocyclic oxazoline structures. The resulting N-propargylated oxindoles are then converted to triazoles using copper-catalyzed azide-alkyne cycloaddition (CuAAC) reactions. This strategy is used for the synthesis of a 64-member pilot-scale library of diverse oxindoles and spirooxindoles. Chapter five describes the first catalytic asymmetric [3+2] allylsilane annulation for the synthesis of cyclopentanes containing an all-carbon quaternary spirocenter. The annulation reaction is catalyzed with a chiral scandium(III)-indapybox complex where a sodium tetrakis[3,5-bis(trifluoromethyl)phenyl]borate (NaBArF) anion is essential for catalytic activity and stereoselectivity. Lactone formation affords evidence for an ester stabilized [beta]-silyl carbocation. Further transformations provide access to N-H spirooxindoles and allow transformation of the silyl group to a hydroxyl moiety. This catalyst complex is also effective for the asymmetric Friedel-Crafts conjugate addition of variety of additional pi-nucleophiles (i.e. indoles, pyrroles, anilines) to [alpha],[beta]-unsaturated alkylidene oxindoles. This methodology is also effective for the diastereoselective synthesis of coumarin and simple malonate derivatives.

Download or read book Heterocycles as Chiral Auxiliaries in Asymmetric Synthesis written by Manfred Braun and published by Springer Nature. This book was released on 2020-12-08 with total page 326 pages. Available in PDF, EPUB and Kindle. Book excerpt: The series Topics in Heterocyclic Chemistry presents critical reviews on present and future trends in the research of heterocyclic compounds. Overall the scope is to cover topics dealing with all areas within heterocyclic chemistry, both experimental and theoretical, of interest to the general heterocyclic chemistry community. The series consists of topic related volumes edited by renowned editors with contributions of experts in the field. All chapters from Topics in Heterocyclic Chemistry are published Online First with an individual DOI. In references, Topics in Heterocyclic Chemistry is abbreviated as Top Heterocycl Chem and cited as a journal.

Download or read book Catalysis in Asymmetric Synthesis written by Vittorio Caprio and published by John Wiley & Sons. This book was released on 2009-03-09 with total page 409 pages. Available in PDF, EPUB and Kindle. Book excerpt: Asymmetric synthesis has become a major aspect of modern organic chemistry. The stereochemical properties of an organic compound are often essential to its bioactivity, and the need for stereochemically pure pharmaceutical products is a key example of the importance of stereochemical control in organic synthesis. However, achieving high levels of stereoselectivity in the synthesis of complex natural products represents a considerable intellectual and practical challenge for chemists. Written from a synthetic organic chemistry perspective, this text provides a practical overview of the field, illustrating a wide range of transformations that can be achieved. The book captures the latest advances in asymmetric catalysis with emphasis placed on non-enzymatic methods. Topics covered include: Reduction of alkenes, ketones and imines Nucleophilic addition to carbonyl compounds Catalytic carbon-carbon bond forming reactions Catalytic reactions involving metal carbenoids Conjugate addition reactions Catalysis in Asymmetric Synthesis bridges the gap between undergraduate and advanced level textbooks and provides a convenient point of entry to the primary literature for the experienced synthetic organic chemist.

Download or read book Progress in Heterocyclic Chemistry written by Gordon Gribble and published by Elsevier. This book was released on 2009-09-03 with total page 573 pages. Available in PDF, EPUB and Kindle. Book excerpt: Progress in Heterocyclic Chemistry (PHC) is an annual review series commissioned by the International Society of Heterocyclic Chemistry (ISHC). Volumes in the series contain both highlights of the previous year's literature on heterocyclic chemistry and articles on emerging topics of particular interest to heterocyclic chemists. The chapters in Volume 21 constitute a systematic survey of the important original material reported in the literature of heterocyclic chemistry in 2008. Additional articles in this volume review "Biocatalytic approaches to chiral heterocycles" and "Ring-expanded ('fat') purines and their nucleoside/nucleotide analogues as broad-spectrum therapeutics." As with previous volumes in the series, Volume 21 apprises academic/industrial chemists and advanced students of developments in heterocyclic chemistry in a convenient format. * Covers the heterocyclic literature published in 2008 * Includes specialized reviews * Features contributions from leading researchers in their fields

Download or read book Multicatalyst System in Asymmetric Catalysis written by Jian Zhou and published by John Wiley & Sons. This book was released on 2014-11-03 with total page 712 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book introduces multi-catalyst systems by describing their mechanism and advantages in asymmetric catalysis. • Helps organic chemists perform more efficient catalysis with step-by-step methods • Overviews new concepts and progress for greener and economic catalytic reactions • Covers topics of interest in asymmetric catalysis including bifunctional catalysis, cooperative catalysis, multimetallic catalysis, and novel tandem reactions • Has applications for pharmaceuticals, agrochemicals, materials, and flavour and fragrance

Download or read book Asymmetric Synthesis of Three Membered Rings written by Hélène Pellissier and published by John Wiley & Sons. This book was released on 2017-03-28 with total page 610 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first handbook to focus on the asymmetric synthesis of different types of three-membered rings. The outstanding and experienced authors have an excellent international reputation and cover cyclopropanes, epoxides and aziridines as well as chiral oxaziridines in equal measure. To this end, they describe in detail different synthetic approaches starting with chiral substrates as well as the application of chiral metal- or organocatalysts. Furthermore, methods for the kinetic resolution of initially racemic products are treated alongside recent advances and novel developments in established techniques for the synthesis of three-membered rings. With its structured composition this is of high interest to scientists in methodological and natural product synthesis as well as those in industrial and pharmaceutical chemistry.

Download or read book Advances in Heterocyclic Chemistry written by and published by Academic Press. This book was released on 2020-04-24 with total page 494 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in Heterocyclic Chemistry is the definitive series in the field - one of great importance to organic chemists, polymer chemists, and many biological scientists. Because biology and organic chemistry increasingly intersect, the associated nomenclature also is being used more frequently in explanations. Written by established authorities in the field from around the world, this comprehensive review combines descriptive synthetic chemistry and mechanistic insight to yield an understanding of how chemistry drives the preparation and useful properties of heterocyclic compounds. - Considered the definitive serial in the field of heterocyclic chemistry - Serves as the go-to reference for organic chemists, polymer chemists and many biological scientists - Provides the latest comprehensive reviews written by established authorities in the field - Combines descriptive synthetic chemistry and mechanistic insight to enhance understanding of how chemistry drives the preparation and useful properties of heterocyclic compounds

Download or read book Catalytic Asymmetric Synthesis written by Takahiko Akiyama and published by John Wiley & Sons. This book was released on 2022-05-27 with total page 798 pages. Available in PDF, EPUB and Kindle. Book excerpt: Catalytic Asymmetric Synthesis Seminal text presenting detailed accounts of the most important catalytic asymmetric reactions known today This book covers the preparation of enantiomerically pure or enriched chemical compounds by use of chiral catalyst molecules. While reviewing the most important catalytic methods for asymmetric organic synthesis, this book highlights the most important and recent developments in catalytic asymmetric synthesis. Edited by two well-qualified experts, sample topics covered in the work include: Metal catalysis, organocatalysis, photoredox catalysis, enzyme catalysis C–H bond functionalization reactions Carbon–carbon bond formation reactions, carbon–halogen bond formation reactions, hydrogenations, polymerizations, flow reactions Axially chiral compounds Retaining the best of its predecessors but now thoroughly up to date with the important and recent developments in catalytic asymmetric synthesis, the 4th edition of Catalytic Asymmetric Synthesis serves as an excellent desktop reference and text for researchers and students, from upper-level undergraduates all the way to experienced professionals in industry or academia.

Download or read book Advances in Asymmetric Synthesis written by Bozzano G Luisa and published by Elsevier. This book was released on 1997-05-16 with total page 329 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in Asymmetric Synthesis

Download or read book Chiral Lewis Acids in Organic Synthesis written by Jacek Mlynarski and published by John Wiley & Sons. This book was released on 2017-06-26 with total page 520 pages. Available in PDF, EPUB and Kindle. Book excerpt: A complete overview covering the application of metal-based chiral Lewis acids from all parts of the periodic table, the Author emphasizes the most recent contributions to the field as well as prominent direction of development. The book discusses the design of chiral complexes as well as a wide spectrum of reactions promoted by various chiral Lewis acids, including water-compatible acids as well as the most important applications in the chemical and pharmaceutical industries. A must-have for catalytic and organic chemists working in the field, both in academia and industry, as well as pharmaceutical and medicinal chemists.

Download or read book Rhodium Catalyzed Enantioselective Desymmetrizations of Oxabicyclic Alkenes and Alkene Difunctionalization Via Nickel Catalyzed Arylcyanation written by Andy Wei Jen Yen and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The synthesis of heterocycles using transition metal catalysis is a topic of broad interest in the field of organic chemistry. Transition metal catalysts allow many diverse bond disconnections to be realized, allowing for many ways to assemble heterocycles. Many of the transformations developed in the Lautens group are aimed at atom economical bond construction processes that streamline synthesis and minimize waste. The arylcyanation reaction and the asymmetric ring opening (ARO) reaction are two examples of methods developed in our group that embody this design principle. Chapter 1 of this thesis describes the development of a nickel-catalyzed arylcyanation reaction for the synthesis of 3,3-disubstituted oxindoles. This method was inspired by our work on the palladium-catalyzed arylcyanation reaction, originally developed to address challenges in the formal synthesis of (+)-corynoline. This nickel-catalyzed reaction uses an air-stable catalyst precursor to achieve a highly practical synthesis of a nitrile-containing oxindole via a domino Heck-cyanide capture cascade. Derivatizations of the nitrile group affords a series of novel heterocyclic scaffolds. Chapter 2 details the discovery and development of a novel enantioselective cycloisomerization reaction of oxabicyclic alkenes. Our work on developing the intramolecular asymmetric ring opening reaction led to the discovery of a novel epoxide synthesis. Specifically, when bridgehead substituted oxabicyclic alkenes with non-nucleophilic side chains are reacted with the [Rh(cod)2]OTf/PPF-PtBu2 catalyst in the absence of an external nucleophile, chiral epoxides are obtained. The synthesis of epoxides through cycloisomerization reactions possesses 100% atom economy and avoids the use of external oxidant. Chapter 3 describes an asymmetric ring opening reaction, specifically to address gaps in the methodology concerning amine nucleophiles. We were inspired by our group's previous attempts to use amino acid derived nucleophiles in the ARO reaction. We developed a way to incorporate amino acids into the ARO reaction by employing their 2-nitrobenzenesulfonamide (nosyl) derivatives as pronucleophiles. Intriguingly, we observed a divergence in reactivity between the diastereomeric hydroxyester products, in that one diastereomer was capable of lactonization and the other was not. This led to the enantioselective synthesis of chiral oxazinones, which are similar to the naphthoxazine class of compounds which possess dopaminergic activity.

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 395 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.