Read Books Online and Download eBooks, EPub, PDF, Mobi, Kindle, Text Full Free.
Synthesis Of A Chiral Ruthenium Organometallic Catalyst To Facilitate The Asymmetric Reduction Of Ketones To Optically Active Alcohols
Download Synthesis Of A Chiral Ruthenium Organometallic Catalyst To Facilitate The Asymmetric Reduction Of Ketones To Optically Active Alcohols full books in PDF, epub, and Kindle. Read online Synthesis Of A Chiral Ruthenium Organometallic Catalyst To Facilitate The Asymmetric Reduction Of Ketones To Optically Active Alcohols ebook anywhere anytime directly on your device. Fast Download speed and no annoying ads. We cannot guarantee that every ebooks is available!
Book Synopsis Synthesis of a Chiral Ruthenium Organometallic Catalyst to Facilitate the Asymmetric Reduction of Ketones to Optically Active Alcohols by : Norman Kabir
Download or read book Synthesis of a Chiral Ruthenium Organometallic Catalyst to Facilitate the Asymmetric Reduction of Ketones to Optically Active Alcohols written by Norman Kabir and published by . This book was released on 1992 with total page 106 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Enantioselective Organocatalysis by : Peter I. Dalko
Download or read book Enantioselective Organocatalysis written by Peter I. Dalko and published by John Wiley & Sons. This book was released on 2007-04-17 with total page 563 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this reference leaders at the forefront of research provide an insight into one of the hottest topics in organic synthesis, focusing on the most important enantioselective reactions. Clearly structured, each entry begins with a concise introduction, including a mechanistic discussion of the reaction, followed by preparative guidelines for newcomers, such as carefully selected working procedures with critical notes for bench chemists, rules of thumb and tips and tricks.
Book Synopsis Catalytic Asymmetric Synthesis by : Takahiko Akiyama
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.
Book Synopsis Development of Optically Active Cyclopentadienyl Ruthenium Complexes and Their Application in Asymmetric Catalysis by : Meera Rao
Download or read book Development of Optically Active Cyclopentadienyl Ruthenium Complexes and Their Application in Asymmetric Catalysis written by Meera Rao and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Novel ruthenium complexes were developed containing a cyclopentadienyl (Cp) ligand tethered to a chiral sulfoxide, which also serves as a ligand. These complexes were synthesized via a [3+2] dehydrogenative cycloaddition between a Ru-[pi]-allyl complex and a terminal acetylene. Using the cycloaddition as a key step, the desired sulfoxide-ligated complexes could be prepared in six linear steps without the use of toxic metallating reagents such as thallium salts. A diverse library of complexes could be accessed through this method, which speaks to the robust nature of the key cycloaddition step. Using these complexes, a CpRu-catalyzed branched-selective asymmetric allylic alkylation (AAA) was developed. Using this method, various oxygen nucleophiles could be alkylated with allyl chloride electrophiles to provide branched ethers, esters and alcohols with high levels of regio- and enantioselectivity. These complexes also were effective in catalyzing an asymmetric redox bicycloisomerization to generate complex [3.1.0]- and [4.1.0]-azabicycles from simple propargyl alcohol substrates.
Book Synopsis Pincer Compounds by : David Morales-Morales
Download or read book Pincer Compounds written by David Morales-Morales and published by Elsevier. This book was released on 2018-04-11 with total page 756 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pincer Compounds: Chemistry and Applications offers valuable state-of-the-art coverage highlighting highly active areas of research—from mechanistic work to synthesis and characterization. The book focuses on small molecule activation chemistry (particularly H2 and hydrogenation), earth abundant metals (such as Fe), actinides, carbene-pincers, chiral catalysis, and alternative solvent usage. The book covers the current state of the field, featuring chapters from renowned contributors, covering four continents and ranging from still-active pioneers to new names emerging as creative strong contributors to this fascinating and promising area. Over a decade since the publication of Morales-Morales and Jensen’s The Chemistry of Pincer Compounds (Elsevier 2007), research in this unique area has flourished, finding a plethora of applications in almost every single branch of chemistry—from their traditional application as very robust and active catalysts all the way to potential biological and pharmaceutical applications. Describes the chemistry and applications of this important class of organometallic and coordination compounds Includes contributions from global leaders in the field, featuring pioneers in the area as well as emerging experts conducting exciting research on pincer complexes Highlights areas of promising and active research, including small molecule activation, earth abundant metals, and actinide chemistry
Book Synopsis Applications of Chiral Aluminum and Boron Catalysts in Asymmetric Synthesis by : Li Zheng
Download or read book Applications of Chiral Aluminum and Boron Catalysts in Asymmetric Synthesis written by Li Zheng and published by . This book was released on 2020 with total page 271 pages. Available in PDF, EPUB and Kindle. Book excerpt: A potent chiral aluminum catalyst has been developed for asymmetric MPV reduction of ketones with broad substrate scope and excellent yields and enantiomeric inductions. The catalyst consists an aluminum core, a VANOL-derived chiral ligand and an isopropoxy group. Different ligands have been screened and reaction parameters have been optimized. A variety of aromatic (both electron-poor and electron-rich) and aliphatic ketones were converted to chiral alcohols in good yields with high enantioselectivities (26 examples, 70-98% yield and 82-99% ee). This method operates under mild conditions (-10 °C) and low catalyst loading (1-10 mol%). Furthermore, this process is catalyzed by the earth-abundant main group element aluminum and employs inexpensive and environmentally benign 2-propanol as hydride source. This catalyst has also been employed in resolution of racemic alcohols. The kinetic resolution of alcohols by Oppenauer oxidation has been achieved with moderate results. The formal dynamic kinetic resolution via Oppenauer oxidation/ MPV reduction sequence has also been examined and discussed, which avoided acylation and the use of enzymes.A highly efficient asymmetric heteroatom Diels-Alder reaction between diene and aldehydes for the construction of 6-membered heterocycles catalyzed by chiral boron catalysts has been developed. A BINOL-derived propeller borate is found to be effective catalyzing the reaction of aromatic aldehydes. A VANOL-derived meso-borate is found to be able to catalyze the reaction of both aromatic and aliphatic aldehydes with high asymmetric inductions. Excellent yields and enantioselectivities have been achieved after optimization. Furthermore, the skeleton of 6-carbon saccharides is synthesized in the reaction of 2-hydoxyacetaldehyde with different protecting groups, which can be derivatized into many saccharide analogs. The mechanism of this reaction is proposed to be concerted based on experiments involving different methods for the reaction quench. A reversal of direction of the asymmetric induction by switching boron to aluminum has been observed. Computational studies show that catalysts derived from boron and aluminum have different geometries at the Lewis acid center.
Book Synopsis Enantioselective Cobalt-catalysed Transformations by : Hélène Pellissier
Download or read book Enantioselective Cobalt-catalysed Transformations written by Hélène Pellissier and published by Royal Society of Chemistry. This book was released on 2018-08-15 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Artificial Metalloenzymes and MetalloDNAzymes in Catalysis by : Montserrat Diéguez
Download or read book Artificial Metalloenzymes and MetalloDNAzymes in Catalysis written by Montserrat Diéguez and published by John Wiley & Sons. This book was released on 2018-02-21 with total page 431 pages. Available in PDF, EPUB and Kindle. Book excerpt: An important reference for researchers in the field of metal-enzyme hybrid catalysis Artificial Metalloenzymes and MetalloDNAzymes in Catalysis offers a comprehensive review of the most current strategies, developed over recent decades, for the design, synthesis, and optimization of these hybrid catalysts as well as material about their application. The contributors—noted experts in the field—present information on the preparation, characterization, and optimization of artificial metalloenzymes in a timely and authoritative manner. The authors present a thorough examination of this interesting new platform for catalysis that combines the excellent selective recognition/binding properties of enzymes with transition metal catalysts. The text includes information on the various applications of metal-enzyme hybrid catalysts for novel reactions, offers insights into the latest advances in the field, and contains an informative perspective on the future: Explores the development of artificial metalloenzymes, the modern and strongly evolving research field on the verge of industrial application Contains a comprehensive reference to the research area of metal-enzyme hybrid catalysis that has experienced tremendous growth in recent years Includes contributions from leading researchers in the field Shows how this new catalysis combines the selective recognition/binding properties of enzymes with transition metal catalysts Written for catalytic chemists, bioinorganic chemists, biochemists, and organic chemists, Artificial Metalloenzymes and MetalloDNAzymes in Catalysis offers a unique reference to the fundamentals, concepts, applications, and the most recent developments for more efficient and sustainable synthesis.
Book Synopsis The Asymmetric Cyclopropanation of Olefins with Optically Active (salen)ruthenium(II) Complexes by : Jason Allen Miller
Download or read book The Asymmetric Cyclopropanation of Olefins with Optically Active (salen)ruthenium(II) Complexes written by Jason Allen Miller and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: As an alternative to using an isolated chiral salen ruthenium catalyst, an optically pure Lewis base could be used to bind axially to the ruthenium center of an achiral catalyst, thus forcing the achiral salen ligand into an asymmetric conformation and inducing stereoselectivity. Enantiomeric excesses as high as 93% have been observed using this method. This novel and exciting modular approach is amenable to parallel-screening optimization and has great potential advantages over traditional catalyst development and synthesis methods.
Book Synopsis Hydrogen Transfer Reactions by : Gabriela Guillena
Download or read book Hydrogen Transfer Reactions written by Gabriela Guillena and published by Springer. This book was released on 2016-09-27 with total page 393 pages. Available in PDF, EPUB and Kindle. Book excerpt: The series Topics in Current Chemistry Collections presents critical reviews from the journal Topics in Current Chemistry organized in topical volumes. The scope of coverage is all areas of chemical science including the interfaces with related disciplines such as biology, medicine and materials science. The goal of each thematic volume is to give the non-specialist reader, whether in academia or industry, a comprehensive insight into an area where new research is emerging which is of interest to a larger scientific audience. Each review within the volume critically surveys one aspect of that topic and places it within the context of the volume as a whole. The most significant developments of the last 5 to 10 years are presented using selected examples to illustrate the principles discussed. The coverage is not intended to be an exhaustive summary of the field or include large quantities of data, but should rather be conceptual, concentrating on the methodological thinking that will allow the non-specialist reader to understand the information presented. Contributions also offer an outlook on potential future developments in the field.
Book Synopsis Principles and Applications of Asymmetric Synthesis by : Guo-Qiang Lin
Download or read book Principles and Applications of Asymmetric Synthesis written by Guo-Qiang Lin and published by John Wiley & Sons. This book was released on 2003-05-29 with total page 536 pages. Available in PDF, EPUB and Kindle. Book excerpt: Asymmetric synthesis remains a challenge to practicing scientistsas the need for enantiomerically pure or enriched compoundscontinues to increase. Over the last decade, a large amount ofliterature has been published in this field. Principles andApplications of Asymmetric Synthesis consolidates and evaluates themost useful methodologies into a one-volume resource for theconvenience of practicing scientists and students. Authored by internationally renowned scientists in the field, thisreliable reference covers more than 450 reactions and includesimportant stoichiometric as well as catalytic asymmetric reactions.The first chapter reviews the basic principles, commonnomenclature, and analytical methods, and the remainder of the bookis organized according to reaction type. The text examines suchtopics as: Carbon-carbon bond formations involving carbonyls, enamines,imines, and enolates Asymmetric C-O bond formations including epoxidation,dihydroxylation, and aminohydroxylation Asymmetric synthesis using the Diels-Alder reaction and othercyclizations Applications to the total synthesis of natural products Use of enzymes in asymmetric synthesis Practicing chemists in the pharmaceutical, fine chemical, andagricultural professions as well as graduate students will findthat Principles and Applications of Asymmetric Synthesis affordscomprehensive and current coverage.
Book Synopsis Synthesis of Chiral Catalysts and Their Application to Asymmetric Cross-coupling Reactions and Selective Hydrogenation by : Hussein Mohamed Galal El-Din Ali
Download or read book Synthesis of Chiral Catalysts and Their Application to Asymmetric Cross-coupling Reactions and Selective Hydrogenation written by Hussein Mohamed Galal El-Din Ali and published by . This book was released on 1990 with total page 392 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Alkaline-Earth Metal Compounds by : Sjoerd Harder
Download or read book Alkaline-Earth Metal Compounds written by Sjoerd Harder and published by Springer. This book was released on 2013-07-20 with total page 282 pages. Available in PDF, EPUB and Kindle. Book excerpt: The series Topics in Organometallic Chemistry presents critical overviews of research results in organometallic chemistry. As our understanding of organometallic structure, properties and mechanisms increases, new ways are opened for the design of organometallic compounds and reactions tailored to the needs of such diverse areas as organic synthesis, medical research, biology and materials science. Thus the scope of coverage includes a broad range of topics in pure and applied organometallic chemistry, where new breakthroughs are being achieved that are of significance to a larger scientific audience. The individual volumes of Topics in Organometallic Chemistry are thematic. Review articles are generally invited by the volume editors.
Book Synopsis Ruthenium in Organic Synthesis by : Shun-Ichi Murahashi
Download or read book Ruthenium in Organic Synthesis written by Shun-Ichi Murahashi and published by John Wiley & Sons. This book was released on 2006-03-06 with total page 398 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this comprehensive book, one of the leading experts, Shun-Ichi Murahashi, presents all the important facets of modern synthetic chemistry using Ruthenium, ranging from hydrogenation to metathesis. In 14 contributions, written by an international authorship, readers will find all the information they need about this fascinating and extraordinary chemistry. The result is a high quality information source and a indispensable reading for everyone working in organometallic chemistry. From the contents: Introduction (S.-I. Murahashi) Hydrogenation and Transfer Hydrogenation (M. Kitamura and R. Noyori) Oxidations (S.-I. Murahashi and N. Komiya) Carbon-Carbon Bond Formations via Ruthenacycle Intermediates (K. Itoh) Carbon-Carbon Bond Formation via pi-Allylruthenium Intermediates (T. Mitsudo) Olefin Metathesis (R. H. Grubbs) Cyclopropanation (H. Nishiyama) Nucleophilic Addition to Alkynes and Reactions via Vinylidene Intermediates (P. Dixneuf) Reactions via C-H Activation (N. Chatani) Lewis Acid Reactions (E. P. Kundig) Reactions with CO and CO2 (T. Mitsudo) Isomerization of Organic Substrates Catalyzed by Ruthenium Complexes (H. Suzuki) Radical Reactions (H. Nagashima) Bond Cleavage Reactions (S. Komiya)
Book Synopsis Heterogeneous Catalysis and Fine Chemicals III by : J. Barbier
Download or read book Heterogeneous Catalysis and Fine Chemicals III written by J. Barbier and published by Elsevier. This book was released on 1993-09-09 with total page 739 pages. Available in PDF, EPUB and Kindle. Book excerpt: Heterogeneous catalysis plays a major role in the organic synthesis of specialty and fine chemicals. However, as the interaction between surface sites and functional groups is complex, more investigations are necessary into the effects of catalysts on the reaction mechanisms. The Third International Symposium on Heterogeneous Catalysis and Fine Chemicals provided an opportunity for discussions on the basic and practical aspects of this subject between researchers, manufacturers and users of solid catalysts for synthesis of fine chemicals. The present volume comprises the invited plenary lectures and research papers classified under the three main headings, hydrogenation, oxidation and acid-catalysis. All papers were refereed. A large variety of reactions are described, the emphasis being on selectivity, taking into account all aspects: chemo-, regio-, and stereoselectivity (including enantioselectivity) and on the change of these selectivities as a function of the characteristics of the catalysts and operating conditions.
Book Synopsis Mechanistic Studies at the Interface Between Organometallic Chemistry and Homogeneous Catalysis by :
Download or read book Mechanistic Studies at the Interface Between Organometallic Chemistry and Homogeneous Catalysis written by and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Mechanistic Studies at the Interface Between Organometallic Chemistry and Homogeneous Catalysis Charles P. Casey, Principal Investigator Department of Chemistry, University of Wisconsin - Madison, Madison, Wisconsin 53706 Phone 608-262-0584 FAX: 608-262-7144 Email: [email protected] http://www.chem.wisc.edu/main/people/faculty/casey.html Executive Summary. Our goal was to learn the intimate mechanistic details of reactions involved in homogeneous catalysis and to use the insight we gain to develop new and improved catalysts. Our work centered on the hydrogenation of polar functional groups such as aldehydes and ketones and on hydroformylation. Specifically, we concentrated on catalysts capable of simultaneously transferring hydride from a metal center and a proton from an acidic oxygen or nitrogen center to an aldehyde or ketone. An economical iron based catalyst was developed and patented. Better understanding of fundamental organometallic reactions and catalytic processes enabled design of energy and material efficient chemical processes. Our work contributed to the development of catalysts for the selective and mild hydrogenation of ketones and aldehydes; this will provide a modern green alternative to reductions by LiAlH4 and NaBH4, which require extensive work-up procedures and produce waste streams. (C5R4OH)Ru(CO)2H Hydrogenation Catalysts. Youval Shvo described a remarkable catalytic system in which the key intermediate (C5R4OH)Ru(CO)2H (1) has an electronically coupled acidic OH unit and a hydridic RuH unit. Our efforts centered on understanding and improving upon this important catalyst for reduction of aldehydes and ketones. Our mechanistic studies established that the reduction of aldehydes by 1 to produce alcohols and a diruthenium bridging hydride species occurs much more rapidly than regeneration of the ruthenium hydride from the diruthenium bridging hydride species. Our mechanistic studies require simultaneous transfer of hydride from ruthenium to the aldehyde carbon and of a proton from the CpOH unit to the aldehyde oxygen and support reduction of the aldehyde without its prior coordination to ruthenium. Another important step in the catalysis is the regeneration of 1 from reaction of H2 with the stable diruthenium bridging hydride complex 2. Studies of the microscopic reverse of this process (hydrogen evolution from 1 which occurs at 80°C) in the presence of alcohol (the product of aldehyde hydrogenation) have shown that a dihydrogen complex is formed reversibly at a rate much faster than hydrogen evolution. Kinetic and theoretical studies in collaboration with Professor Qiang Cui of Wisconsin indicated an important role for alcohol in mediating transfer of hydrogen to ruthenium. One key to developing more active catalysts was to destabilize the bridging hydride intermediate 2 to prevent its formation or to speed its conversion to a reactive monohydride 1 by reaction with H2. We found several successful ways to destabilize the bridging hydride and to obtain more active catalysts. Most recently, we discovered related iron catalysts for hydrogenation that do not form dimers; the cost advantage of iron catalysts is spectacular. Iron Catalysts. In an exciting development, we found that a related iron complex is also a very active ketone hydrogenation catalyst. This hydrogenation catalyst shows high chemoselectivity for aldehydes, ketones, and imines and isolated C=C, CoC, C-X, -NO2, epoxides, and ester functions are unaffected by the hydrogenation conditions. Mechanistic studies have established a reversible hydrogen transfer step followed by rapid dihydrogen activation. The same iron complex also catalyzes transfer hydrogenation of ketones.
Book Synopsis Asymmetric and Organometallic Catalysis Mediated by a Chiral Supramolecular Host by : Casey Jameson Brown
Download or read book Asymmetric and Organometallic Catalysis Mediated by a Chiral Supramolecular Host written by Casey Jameson Brown and published by . This book was released on 2011 with total page 103 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chapter 1. An overview of supramolecular catalysis is presented with attention to the diverse strategies used in developing these materials. Different strategies for the design and preparation of chiral supramolecular structures are described along with their applications to enantioselective binding and catalysis. The intrinsically chiral M4L612− supramolecular assembly developed by the Raymond group is introduced, and its catalytic scope is reviewed. Chapter 2. The development of an asymmetric variant of the aza-Cope transformation is presented. Application of the resolved Ga4L612− assembly to this catalytic transformation gives modest but significant enantioselectivity (up to 64% ee) with a varied scope of allyl enammonium cations. This represents the first reported example of asymmetric supramolecular catalysis with substantial enantioselectivity and catalytic turnover. Use of a relatively unreactive substrate allowed characterization of a host-substrate complex by X-ray diffraction, giving insight into the means of enantiodifferentiation by the chiral host. Additionally, the structure of the M4L612− assembly was modified by substituting other trivalent cations (Fe3, 3) into the M4L612− host, modulating the enantioselectivity of the rearrangement. Efforts to emulate allosteric regulation using externally associated chiral cations are also described. Chapter 3. The engineering of a high-turnover supramolecular catalyst containing a cationic ruthenium complex is described. The RuCp(PMe3)(MeCN)2 cation, an allyl alcohol isomerization catalyst, was incorporated into the Ga4L612− assembly. While encapsulated, the organometallic complex experiences only mild rate attenuations, while maintaining its remarkably high activity. This hybrid catalyst is capable of more than 1000 turnovers, eclipsing other known supramolecular catalysts. The kinetics of catalysis are also analyzed, revealing inhibition both by acetonitrile and the allyl alcohol substrates. The protection offered by encapsulation in the assembly also allowed the preparation of the larger RuCp*(PMe3)(MeCN)2+ complex, which is both stable and catalytically active. Preliminary investigations of this complex are described. Chapter 4. Cationic gold(I) catalysts encapsulated inside assembly 14L6 assembly, R3PAuX (X = Cl, Br) complexes have been found to lose their halide ligand and reside in the nanovessel's cavity as the free cation. This host-guest complex is catalytically active in both the hydroalkoxylation and hydroamination of allenes, generating cyclic, chiral ethers and amines. The rate of catalysis for the bound gold cation is observed to be higher than that for the bulk-solution gold species by about an order of magnitude. Efforts to incorporate this gold catalyst into the resolved Ga4L612−assembly are detailed, though this family of organometallic catalysts has thus far been incompatible with the resolved Ga4L612− assembly.
