Download or read book Science of Synthesis Metal Catalyzed Cyclization Reactions written by Shuanhu Gao and published by Thieme. This book was released on 2016-12-14 with total page 818 pages. Available in PDF, EPUB and Kindle. Book excerpt: Significant advances in metal-catalyzed reactions, especially cyclizations, have dramatically improved the efficiency of organic synthesis over the last three decades. To date these transformations are widely used in the area of synthesis of both natural products and therapeutic agents. "Science of Synthesis: Metal-Catalyzed Cyclization Reactions" presents the most commonly used and significant metal-catalyzed reactions for modern organic synthesis. The basic principles, the current state of the art, scope, limitations, and mechanism of these reactions are also discussed. Typical examples of target synthesis are provided to help inspire further applications. Volume 1 covers intramolecular coupling reactions (including Heck reactions), intramolecular allylations, and cyclopropane and cyclopropene ring openings. Also included are cyclization reactions of alkenes, alkynes, and allenes, cycloisomerizations, and intramolecular C-N and C-O bond formation.
Download or read book Science of Synthesis Metal Catalyzed Cyclization Reactions written by Shengming Ma and published by Thieme. This book was released on 2016-12-14 with total page 1198 pages. Available in PDF, EPUB and Kindle. Book excerpt: Significant advances in metal-catalyzed reactions, especially cyclizations, have dramatically improved the efficiency of organic synthesis over the last three decades. To date these transformations are widely used in the area of synthesis of both natural products and therapeutic agents. "Science of Synthesis: Metal-Catalyzed Cyclization Reactions" presents the most commonly used and significant metal-catalyzed reactions for modern organic synthesis. The basic principles, the current state of the art, scope, limitations, and mechanism of these reactions are also discussed. Typical examples of target synthesis are provided to help inspire further applications. Volume 2 covers epoxidations, aziridinations, cyclopropanations, and Pauson-Khand reactions, as well as a wide range of cycloaddition processes, radical cyclizations, and ring-closing metathesis.
Download or read book Metal catalyzed Cyclization Reactions written by Shengming Ma and published by Thieme Chemistry. This book was released on 2016 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Significant advances in metal-catalyzed reactions, especially cyclizations, have dramatically improved the efficiency of organic synthesis over the last three decades. To date these transformations are widely used in the area of synthesis of both natural products and therapeutic agents. Science of Synthesis: Metal-Catalyzed Cyclization Reactions presents the most commonly used and significant metal-catalyzed reactions for modern organic synthesis. The basic principles, the current state of the art, scope, limitations, and mechanism of these reactions are also discussed. Typical examples of target synthesis are provided to help inspire further applications. Volume 1 covers intramolecular coupling reactions (including Heck reactions), intramolecular allylations, and cyclopropane and cyclopropene ring openings. Also included are cyclization reactions of alkenes, alkynes, and allenes, cycloisomerizations, and intramolecular C-N and C-O bond formation. Volume 2 covers epoxidations, aziridinations, cyclopropanations, and Pauson-Khand reactions, as well as a wide range of cycloaddition processes, radical cyclizations, and ring-closing metathesis.
Download or read book Metal catalyzed Cyclization Reactions written by J. M. Alderson and published by . This book was released on 2016 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Metal Catalyzed Cyclization Reactions 2 written by S. Ma and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Metal Catalyzed Cyclization Reactions 1 written by S. Ma and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Metal catalyzed Cyclization 2 written by U. Bora and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Metal catalyzed Cross coupling Reactions written by François Diederich and published by John Wiley & Sons. This book was released on 2008-07-11 with total page 540 pages. Available in PDF, EPUB and Kindle. Book excerpt: Carbon-carbon bond forming reactions are arguably the most important processes in chemistry, as they represent key steps in the building of complex molecules from simple precursors. Among these reactions, metal-catalyzed cross-coupling reactions are extensively employed in a wide range of areas of preparative organic chemistry, ranging from the synthesis of complex natural products, to supramolecular chemistry, and materials science. In this work, a dozen internationally renowned experts and leaders in the field bring the reader up to date by documenting and critically analyzing current developments and uses of metal-catalyzed cross-coupling reactions. A particularly attractive and useful feature, that enhances the practical value of this monograph, is the inclusion of key synthetic protocols, in experimental format, chosen for broad utility and application. This practice-oriented book can offer the practitioner short cuts to ensure they remain up-to-date with the latest developments.
Download or read book Science of Synthesis written by Shengming Ma and published by . This book was released on 2016 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Recent Developments in the Synthesis of Heterocycles by Transition metal Catalyzed Cyclization Reactions written by Bartolo Gabriele and published by . This book was released on 2006 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Explorations on Transition Metal Catalyzed Enantioselective Cyclization Reactions and Applications of Thiourea Ligands written by Min Yang and published by Open Dissertation Press. This book was released on 2017-01-27 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation, "Explorations on Transition Metal-catalyzed Enantioselective Cyclization Reactions and Applications of Thiourea Ligands" by Min, Yang, 楊敏, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. Abstract: Abstract of thesis entitled EXPLORATIONS ON TRANSITION METAL- CATALYZED ENANTIOSELECTIVE CYCLIZATION REACTIONS AND APPLICATIONS OF THIOUREA LIGANDS submitted by Yang Min for the Degree of Doctor of Philosophy at The University of Hong Kong in November 2005 Transition metal-catalyzed carbon-carbon bond formation and carbon- heteroatom bond formation are powerful tools in synthetic chemistry, and have been widely applied in the construction of cyclic compounds. The aim of this project is to develop enantioselective cyclization reactions by the application of transition metals and chiral ligands. A chiral Lewis acid-promoted highly enantioselective intramolecular carbonyl ene cyclization reaction of unsaturated α-keto esters has been developed (Scheme 1). In the presence of chiral Lewis acids such as [Sc((R, R)-Ph- pybox)](OTf) and [Cu((S, S)-Ph-box)](OTf), unsaturated α-keto esters (1.1c-f) 3 2 underwent carbonyl ene reactions smoothly under mild conditions to give cis-1- hydroxyl-2-vinyl esters (1.2c-f) with two new chiral centers, including a quaternary one, in good yields (> 81%), excellent cis stereoselectivities (diastereomeric ratio up to 50:1), and good to excellent enantiomer excesses (up to 99%). This easy entry to the highly functionalized chiral cyclic products under mild conditions will definitely make this catalytic enantioselective method a useful tool for the construction of the chiral skeletons of many medicinal agents and bioactive molecules. A new palladium-catalyzed enantioselective oxidative tandem cyclization method has been developed. In the presence of a catalytic amount of Pd(tfa) /(-)- sparteine with cheap and environmentally benign molecular oxygen as the terminal oxidant, a series of polycyclic indoline derivatives 2.2 with up to two stereocenters (2.2fb) are readily prepared in a single step in good yields and moderate to good enantiomer excesses (up to 91%; Scheme 2). These represent the first examples of enantioselective oxidative tandem cyclization reactions under aerobic conditions. A class of sterically bulky cyclic thiourea ligands (L1-11, Figure 1) have been synthesized. Ligand L1, with bulky t-butyl groups on the aryl moiety, was found to be effective in the palladium-catalyzed oxidation of alcohols under aerobic conditions, in which L1 exhibited good stability to oxidizing agents and efficiently prevented palladium from undergoing aggregation (Scheme 3). This new catalyst system has been applied to a wide variety of substrates such as benzylic alcohols, aliphatic secondary alcohols and allylic alcohols, producing the desired carbonyl compounds in moderate to excellent yields. However, the attempts to apply the chiral thiourea ligands (L7-11) to the palladium-catalyzed oxidative kinetic resolution of secondary alcohols did not give satisfactory results. Scheme 1 Chiral Lewis acid OEt OEt OH 81 87% yield n CH Cl, rt H 2 2 dr > 50:1 75 91% ee _ _ 1.1c 1.2c d d n = 1, 2 Chiral Lewis Acid: or Sc(OTf), Cu(OTf), 2 NN N N Ph Ph Ph Ph Cu(OTf) (20 mol%) 5R 5R 1R OR 1S OR OR L* (22 mol%), CH Cl, rt 2 2 OH 2R 2S OH L* = NN major 1.3e/f 1.1e R = CH 1.2e/f Ph Ph R = Bn 1.1f 91 94% yie
Download or read book Transition Metal Catalyzed Cyclization and Synthesis of Triptolide Analogs written by Jiehui Pan and published by Open Dissertation Press. This book was released on 2017-01-27 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation, "Transition Metal Catalyzed Cyclization and Synthesis of Triptolide Analogs" by Jiehui, Pan, 潘杰輝, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. Abstract: Abstract of thesis entitled TRANSITION METAL CATALYZED CYCLIZATION AND SYNTHESIS OF TRIPTOLIDE ANALOGS Submitted by Pan Jiehui for the Degree of Doctor of Philosophy at The University of Hong Kong in March 2006 (-)-Triptonide, (-)-triptolide, and 16-hydroxytriptolide are bioactive natural product, isolated from the Chinese medicinal plant Tripterygium wilfordii Hook. F. (Lei Gong Teng). They show potent immunosuppressive, antileukemic, and antifertile activities. However, their mechanisms of actions still remain elusive, and only limited structure-activity relationship studies of triptolide and its analogs have been carried out. I have successfully synthesized bioactive alkyne-derived triptolide probe and azide functionalized fluorophore tags, which were designed for identifying the receptors of triptolide by using the click chemistry method. A model reaction simulating the cycloaddition between the bioactive triptolide probe and rhodamine tag has been successfully accomplished, which could be applied in the search for the receptors of triptolide. Synthetic studies of triptolide analogs could provide new methods to prepare analogs containing moieties different from the original triptolide molecule, and possibly enable its curative effects to be distinguished from its toxic effects. Two efficient cross-coupling methods including the Heck reaction and the Sonogashira coupling have been utilized for the introduction of the C-13 side chain of triptolide analogs. These protocols provide new ways to modify the triptolide molecule at the C-13 position in addition to the Claisen rearrangement. Several novel dimeric triptolide analogs with different functionalities at the C-13 position have been prepared. The exploration of transition metal-catalyzed cyclization reactions has been at the frontier of organic synthesis. I have prepared several sterically bulky N, N'-disubstituted cyclic thiourea-gold(I) complexes. The crystal structures of the complexes reveal the different coordination nature of sulphur in these complexes in the solid state. In solution, a ligand scrambling reaction has been observed with the N, N'-dialkyl cyclic thiourea ligands. Useful information about the equilibrium of ligand scrambling reaction has been obtained from the H NMR experiments. I have used bulky N, N'-disubstituted cyclic thioureas as effective ligands for the Au(I)-catalyzed carbocyclization of 1,3-dicarbonyl compounds with alkynes. The reactions can be readily conducted with a low catalyst loading, short reaction time in an "open flask" system and in high yields. In addition, I have demonstrated an application of the bulky N, N'-disubstituted cyclic thiourea-Au(I) complexes in the cycloisomerization of acetylenic 1,3-dicarbonyl compounds to form γ-lactones and γ-lactams. These reactions can be readily conducted with low catalytic loading in an "open flask" system and provide a new method to generate γ-lactones and γ-lactams. DOI: 10.5353/th_b3776596 Subjects: Ring formation (Chemistry) Bioactive compounds - Synthesis Transition metal catalysts
Download or read book Cyclization Reactions written by C. Thebtaranonth and published by CRC Press. This book was released on 1993-05-01 with total page 392 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cyclization Reactions provides a quick update of the latest advances in cyclization reactions. It covers the basic principles of cyclization chemistry, emphasizing practical applications. Chapters are organized according to the different cyclization intermediates-cationic, radical, anionic, and metal complex intermediates. The last chapter covers macrolactonization, vicinal tricarbonal, and Bergman (enediyne) reactions, which are of particular interest today. More than 2,600 structures illustrate key concepts throughout the book. Various cyclizations are organized into mechanistic groups to help researchers choose and change between methods when searching for maximum efficiency in synthesis. Critical coverage of the literature up to 1992 is provided. Cyclization Reactions is essential reading for anyone involved in the synthesis of ring compounds or who is seeking a rapid overview of the field. Newcomers as well as experienced researchers will benefit from this book. It also is excellent reference material for students at the advanced undergraduate and graduate levels.
Download or read book Synthesis of Heterocycles via Metal Catalyzed Reactions that Generate One or More Carbon Heteroatom Bonds written by John P. Wolfe and published by Springer. This book was released on 2013-09-11 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt: Synthesis of Saturated Heterocycles via Metal-Catalyzed Alkene Carboamination or Carboalkoxylation Reactions, by John P. Wolfe Synthesis of Saturated Heterocycles via Metal-Catalyzed Alkene Diamination, Aminoalkoxylation, or Dialkoxylation Reactions, by Sherry R. Chemler Synthesis of Heterocycles via Metal-Catalyzed Wacker-Type Oxidative Cyclization Reactions of Alkoxy- or Amino-Alkenes, by Wanbin Zhang Synthesis of Saturated Heterocycles via Metal-Catalyzed Hydroamination or Hydroalkoxylation Reactions, by Lisa D. Julian Synthesis of Saturated Heterocycles via Metal-Catalyzed Allylic Alkylation Reactions, by Aaron Aponick Synthesis of Heterocycles via Metal-Catalyzed Cascade/Domino Reactions that Generate a C–N or C–O Bond, by Mark Lautens Synthesis of Saturated Heterocycles via Metal-Catalyzed Formal Cycloaddition Reactions that Generate a C–N or C–O Bond, by Jerome Waser
Download or read book Metal Catalyzed Cascade Reactions written by Thomas J.J. Müller and published by Springer. This book was released on 2010-11-18 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book highlights cyclization via carbopalladation and acylpalladation and Heck-pericyclic sequences. They discuss p-allyl palladium-based cascade reactions, Michael-type additions as an entry to transition-metal-promoted cyclizative transformations, and sequential or consecutive palladium-catalyzed processes, and show Pauson-Khand cascades, metal-catalyzed cyclizations of acyclic precursors, as well as cascade and sequential ruthenium-catalyzed transformations. This is a comprehensive overview of an exciting and highly dynamic, and innovative methodological concept.
Download or read book Tunable Transition Metal catalyzed Group Transfer Reactions and Subsequent Cyclization Reactions written by Alicia Marie Phelps and published by . This book was released on 2015 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Controlling the outcome of transition metal-catalyzed group transfer reactions represents a powerful strategy for assembling complex synthesis targets. Herein, we describe two such selective methods, as well as a further method for the functionalization of allene products. First, a carbene transfer in an allene substrate that is controlled by selection of transition metal catalyst is described. These products represent the building blocks of complex frameworks, and a gold-catalyzed carbocyclization from these products is described that leads to fully functionalized cyclopentane rings in only a few steps from the allene substrate. Finally, a silver-catalyzed C-H insertion method that can select between different types of C-H bonds is shown. This methodology complements the others as a strategy for late-stage functionalization of the constructed scaffolds.
Download or read book Metal catalyzed Intramolecular Cyclization Reactions of Alkynyl Alpha Diazoketones written by Christopher John Dinsmore and published by . This book was released on 1991 with total page 462 pages. Available in PDF, EPUB and Kindle. Book excerpt:
