Title Recent Advances in Transition-Metal-Catalyzed
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This Thesis Has Been Submitted in Fulfilment of the Requirements for a Postgraduate Degree (E.G
This thesis has been submitted in fulfilment of the requirements for a postgraduate degree (e.g. PhD, MPhil, DClinPsychol) at the University of Edinburgh. Please note the following terms and conditions of use: • This work is protected by copyright and other intellectual property rights, which are retained by the thesis author, unless otherwise stated. • A copy can be downloaded for personal non-commercial research or study, without prior permission or charge. • This thesis cannot be reproduced or quoted extensively from without first obtaining permission in writing from the author. • The content must not be changed in any way or sold commercially in any format or medium without the formal permission of the author. • When referring to this work, full bibliographic details including the author, title, awarding institution and date of the thesis must be given. Development of Novel Metal-Catalysed Methods for the Transformation of Ynamides Thesis Submitted in Accordance with the Requirements of The University of Edinburgh for the Degree of Doctor of Philosophy By Donna L. Smith Supervised by Dr. Hon Wai Lam School of Chemistry College of Science and Engineering 2013 Declaration I hereby declare that, except where specific reference is made to other sources, the work contained within this thesis is the original work of my own research since the registration of the PhD degree in September 2009, and any collaboration is clearly indicated. This thesis has been composed by myself and has not been submitted, in whole or part, for any other degree, diploma or other qualification. Donna L. Smith 2 Abstract I. Rhodium-Catalysed Carbometalation of Ynamides using Organoboron Reagents As an expansion of existing procedures for the carbometalation of ynamides, it was discovered that [Rh(cod)(MeCN)2]BF4 successfully promotes the carbometalation of ynamides with organoboron reagents. -
Research Report Fürstner 2017-2019 603.42 Kb
Research Programs – Organometallic Chemistry 2.4 Advances in Metal-Carbene Chemistry Department of Organometallic Chemistry by Alois Fürstner ABSTRACT: The major lines of research in this Department continue to be: (i) alkyne metathesis, (ii) iron catalyzed C-C-bond formation, (iii) π-acid catalysis using platinum, gold and rhodium complexes, and (iv) unorthodox catalytic addition reactions. All areas are prospering, including the application of the in-house methodology to target-oriented synthesis; yet, it was the field of ruthenium-catalyzed addition chem- istry which led to the most perplexing and (hopefully) significant results. For the unexpected intervention of discrete metal carbenes as reac- tive intermediates, the major findings in this area are discussed together with our recent contributions to the related field of rhodium carbene chemistry. Ruthenium. cis-Delivery of H2 to a π-system of an unsaturated cal outcome is astounding, if one considers that conventional trans- substrate is the canonical course of metal catalyzed hydrogenation hydroboration is the textbook example for a cis-addition process via reactions. This stereochemical paradigm remained basically unchal- a four-membered transition state under frontier-orbital control. All lenged since the pioneering work of Sabatier until our group re- newly discovered trans-hydrometalation reactions break this fun- ported the semi-reduction of internal alkynes with the aid of damental stereochemical rule; importantly, they are robust, distin- [Cp*Ru]-based catalysts. The reaction clearly violates this funda- guished by excellent functional group compatibility, and have mental rule and affords E-alkenes by direct trans-hydrogenation already stood the test of natural product synthesis in a number of (Scheme 1). -
Catalytic Enantioselective Carbon-Carbon Bond Formation Using Cycloisomerization Reactions
View Online / Journal Homepage / Table of Contents for this issue Chemical Science Dynamic Article LinksC< Cite this: Chem. Sci., 2012, 3, 2899 www.rsc.org/chemicalscience MINIREVIEW Catalytic enantioselective carbon-carbon bond formation using cycloisomerization reactions Iain D. G. Watsona and F. Dean Toste*b Received 30th April 2012, Accepted 7th June 2012 DOI: 10.1039/c2sc20542d This review describes important recent advancements in asymmetric cycloisomerization reactions. A wide variety of catalytic and asymmetric strategies have been applied to these reactions over the past twenty years. Cycloisomerization reactions have the ability to produce diverse polycyclic compounds in excellent yields and selectivity. They constitute a powerful and efficient strategy for asymmetric carbon- carbon bond formation in cyclic compounds. Enyne and related olefin cyclizations comprise the majority of reactions of this type and important advances have recently occurred in this area. However, significant changes have also occurred in the area of classical cyclization as well as intramolecular hydroacylation and C–H activation initiated cyclization and these will also be described. 1 Introduction The purpose of this review is to describe important new advances in asymmetric cycloisomerization reactions. In partic- The synthesis of rings is central to the art of organic synthesis. ular, this review will focus on enantioselective carbon-carbon Cyclic compounds abound in chemistry, from strained three bond forming cycloisomerizations. Many aspects of cyclo- membered rings to macrocyclic monsters. A common synthetic isomerization reactions have already been reviewed,3 including challenge is the creation of a ring within a certain target mechanistic4 and asymmetric aspects of the reaction.5 This compound. -
EI-ICHI NEGISHI Herbert C
MAGICAL POWER OF TRANSITION METALS: PAST, PRESENT, AND FUTURE Nobel Lecture, December 8, 2010 by EI-ICHI NEGISHI Herbert C. Brown Laboratories of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, IN 47907-2084, U.S.A. Not long ago, the primary goal of the synthesis of complex natural products and related compounds of biological and medicinal interest was to be able to synthesize them, preferably before anyone else. While this still remains a very important goal, a number of today’s top-notch synthetic chemists must feel and even think that, given ample resources and time, they are capable of synthesizing virtually all natural products and many analogues thereof. Accepting this notion, what would then be the major goals of organic synthesis in the twenty-first century? One thing appears to be unmistakably certain. Namely, we will always need, perhaps increasingly so with time, the uniquely creative field of synthetic organic and organometallic chemistry to prepare both new and existing organic compounds for the benefit and well-being of mankind. It then seems reasonably clear that, in addition to the question of what compounds to synthesize, that of how best to synthesize them will become increasingly important. As some may have said, the primary goal would then shift from aiming to be the first to synthesize a given compound to seeking its ultimately satisfactory or “last synthesis”. If one carefully goes over various aspects of organic synthetic methodology, one would soon note how primitive and limited it had been until rather recently, or perhaps even today. For the sake of argument, we may propose here that the ultimate goal of organic synthesis is “to be able to synthesize any desired and fundamentally synthesizable organic compounds (a) in high yields, (b) efficiently (in as few steps as possible, for example), (c) selectively, preferably all in t98–99% selectivity, (d) economically, and (e) safely, abbreviated hereafter as the y(es)2 manner.” with or without catalyst R1M + R2X R1R2 + MX R1, R2: carbon groups. -
Transition Metal Hydrides That Mediate Catalytic Hydrogen Atom Transfers
Transition Metal Hydrides that Mediate Catalytic Hydrogen Atom Transfers Deven P. Estes Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Graduate School of Arts and Sciences COLUMBIA UNIVERSITY 2014 © 2014 Deven P. Estes All Rights Reserved ABSTRACT Transition Metal Hydrides that Mediate Catalytic Hydrogen Atom Transfers Deven P. Estes Radical cyclizations are important reactions in organic chemistry. However, they are seldom used industrially due to their reliance on neurotoxic trialkyltin hydride. Many substitutes for tin hydrides have been developed but none have provided a general solution to the problem. Transition metal hydrides with weak M–H bonds can generate carbon centered radicals by hydrogen atom transfer (HAT) to olefins. This metal to olefin hydrogen atom transfer (MOHAT) reaction has been postulated as the initial step in many hydrogenation and hydroformylation reactions. The Norton group has shown MOHAT can mediate radical cyclizations of α,ω dienes to form five and six membered rings. The reaction can be done catalytically if 1) the product metalloradical reacts with hydrogen gas to reform the hydride and 2) the hydride can perform MOHAT reactions. The Norton group has shown that both CpCr(CO)3H and Co(dmgBF2)2(H2O)2 can catalyze radical cyclizations. However, both have significant draw backs. In an effort to improve the catalytic efficiency of these reactions we have studied several potential catalyst candidates to test their viability as radical cyclization catalysts. I investigate the hydride CpFe(CO)2H (FpH). FpH has been shown to transfer hydrogen atoms to dienes and styrenes. I measured the Fe–H bond dissociation free energy (BDFE) to be 63 kcal/mol (much higher than previously thought) and showed that this hydride is not a good candidate for catalytic radical cyclizations. -
Transition Metals for Organic Synthesis
Matthias Beller, Carsten Bolm Transition Metals for Organic Synthesis Building Blocks and Fine Chemicals © WILEY-VCH Weinheim • New York • Chichester • Brisbane • Singapore • Toronto Contents Volume 1 1 General 1 1.1 Basic Aspects of Organic Synthesis with Transition Metals (Barry M. Trost) 3 1.1.1 Chemoselectivity 4 1.1.2 Regioselectivity 6 1.1.3 Diastereoselectivity 7 1.1.4 Enantioselectivity 9 1.1.5 Atom Economy 10 1.1.6 Conclusion 11 References 12 1.2 Concepts for the Use of Transition Metals in Industrial Fine Chemical Synthesis (Wilhelm Keim) 14 1.2.1 General Principles 14 1.2.2 Use of Transition Metals in Fine Chemical Synthesis .... 15 1.2.3 Why are Transition Metals used in Fine Chemical Synthesis? 21 1.2.4 Considerations for the Future 22 References 22 2 Transition Metal-catalyzed Reactions 23 2.1 New Opportunities in Hydroformylation: Selected Syntheses of Intermediates and Fine Chemicals (Carlo Botteghi, Mauro Marchetti, Stefano Paganelli) ... 25 2.1.1 Introduction 25 2.1.2 Building Blocks for Pharmaceutical and Natural Products . 26 2.1.3 Building Blocks for Agrochemicals 40 2.1.4 Concluding Remarks 43 References 45 viii Contents 2.2 Hydrocarboxylation and Hydroesterification Reactions Catalyzed by Transition Metal Complexes (Bassam El Ali, Howard Alper) 49 2.2.1 Introduction 49 2.2.2 Intermolecular Hydrocarboxylation and Hydroesterification of Unsaturated Substrates 49 2.2.2.1 Hydrocarboxylation of Alkenes 49 2.2.2.2 Hydroesterification of Alkenes 53 2.2.2.3 Hydrocarboxylation and Hydroesterification of Allenes and Dienes -
Catalytic Systems Based on Cp2zrx2 (X = Cl, H), Organoaluminum
catalysts Article Catalytic Systems Based on Cp2ZrX2 (X = Cl, H), Organoaluminum Compounds and Perfluorophenylboranes: Role of Zr,Zr- and Zr,Al-Hydride Intermediates in Alkene Dimerization and Oligomerization Lyudmila V. Parfenova 1,* , Pavel V. Kovyazin 1, Almira Kh. Bikmeeva 1 and Eldar R. Palatov 2 1 Institute of Petrochemistry and Catalysis of Russian Academy of Sciences, Prospekt Oktyabrya, 141, 450075 Ufa, Russia; [email protected] (P.V.K.); [email protected] (A.K.B.) 2 Bashkir State University, st. Zaki Validi, 32, 450076 Ufa, Russia; [email protected] * Correspondence: [email protected]; Tel.: +7-347-284-3527 i i Abstract: The activity and chemoselectivity of the Cp2ZrCl2-XAlBu 2 (X = H, Bu ) and [Cp2ZrH2]2- ClAlEt2 catalytic systems activated by (Ph3C)[B(C6F5)4] or B(C6F5)3 were studied in reactions with 1-hexene. The activation of the systems by B(C6F5)3 resulted in the selective formation of head- to-tail alkene dimers in up to 93% yields. NMR studies of the reactions of Zr complexes with organoaluminum compounds (OACs) and boron activators showed the formation of Zr,Zr- and Zr,Al-hydride intermediates, for which diffusion coefficients, hydrodynamic radii, and volumes were estimated using the diffusion ordered spectroscopy DOSY. Bis-zirconium hydride clusters of type x[Cp ZrH ·Cp ZrHCl·ClAlR ]·yRnAl(C F ) − were found to be the key intermediates of alkene 2 2 2 2 6 5 3 n dimerization, whereas cationic Zr,Al-hydrides led to the formation of oligomers. Citation: Parfenova, L.V.; Kovyazin, P.V.; Bikmeeva, A.K.; Palatov, E.R. -
Transmetalation
Organic Chemistry IV Organometallic Chemistry for Organic Synthesis Prof. Paul Knochel LMU 2015 1 OCIV Prüfung: Freitag 17. Juli 2015 9-11 Uhr Wieland HS Wiederholungsklausur: Donnerstag 17. September 2015 12-14 Uhr Baeyer HS 2 Recommended Literature 1. F. A. Carey, R. J. Sundberg, Advanced Organic Chemistry, Fifth Edition Part A and Part B, Springer, 2008, ISBN-13: 978-0-387-68346-1 2. R. Brückner, Organic Mechanisms, Springer, 2010, ISBN: 978-3-642- 03650-7 3. L. Kürti, B. Czako, Strategic applications of named reactions in organic synthesis, Elsevier, 2005, ISBN-13: 978-0-12-429785-2 4. N. Krause, Metallorganische Chemie, Spektrum der Wissenschaft, 1996, ISBN: 3-86025-146-5 5. R. H. Crabtree, The organometallic chemistry of transition metals, Wiley- Interscience, 2005, ISBN: 0-471-66256-9 6. M. Schlosser, Organometallics in Synthesis – A manual, 2nd edition, Wiley, 2002, ISBN: 0-471-98416-7 7. K. C. Nicolaou, T. Montagnon, Molecules that changed the world, Wiley- VCH, 2008, ISBN: 978-527-30983-2 8. J. Hartwig, Organotransition Metal Chemistry: From Bonding to Catalysis, Palgrave Macmillan, 2009, ISBN-13: 978-1891389535 9. P. Knochel, Handbook of Functionalized Organometallics, Volume 1 und 2, Wiley-VCH, 2005, ISBN-13: 978-3-527-31131-6 3 Importance of organometallics 4 Industrial production Industrial annual production of various organometallics Organometallic production [T / year] Si 700 000 Pb 600 000 Al 50 000 Sn 35 000 Li 900 5 Organometallic reagents and catalysts for the organic synthesis 6 Historic point of view 1757 - Louis Cadet de Gassicourt (parisian apothecary) E. Frankland (1848), University of Marburg, initial goal: synthesis of an ethyl radical Universität Marburg (1848) 7 Organometallic chemistry of the XIX century 8 Organometallic chemistry of the XIX century 9 Reactivity of the Grignard reagents 10 Historic point of view Victor Grignard (1900) Karl Ziegler (1919) 11 Historic point of view first transition metal organometallics: Hein (1919) 12 Historic point of view 1951 : synthesis of ferrocene Pauson (Scotland) 7. -
Using Carbon Dioxide As a Building Block in Organic Synthesis
REVIEW Received 10 Jul 2014 | Accepted 21 Nov 2014 | Published 20 Jan 2015 DOI: 10.1038/ncomms6933 Using carbon dioxide as a building block in organic synthesis Qiang Liu1, Lipeng Wu1, Ralf Jackstell1 & Matthias Beller1 Carbon dioxide exits in the atmosphere and is produced by the combustion of fossil fuels, the fermentation of sugars and the respiration of all living organisms. An active goal in organic synthesis is to take this carbon—trapped in a waste product—and re-use it to build useful chemicals. Recent advances in organometallic chemistry and catalysis provide effective means for the chemical transformation of CO2 and its incorporation into synthetic organic molecules under mild conditions. Such a use of carbon dioxide as a renewable one-carbon (C1) building block in organic synthesis could contribute to a more sustainable use of resources. more sensible resource management is the prerequisite for the sustainable development of future generations. However, when dealing with the feedstock of the chemical Aindustry, the level of sustainability is still far from satisfactory. Until now, the vast majority of carbon resources are based on crude oil, natural gas and coal. In addition to biomass, CO2 offers the possibility to create a renewable carbon economy. Since pre-industrial times, the amount of CO2 has steadily increased and nowadays CO2 is a component of greenhouse gases, which are primarily responsible for the rise in atmospheric temperature and probably abnormal changes in the global climate. This increase in CO2 concentration is largely due to the combustion of fossil fuels, which are required to meet the world’s energy demand1. -
Encyclopedia of Inorganic Chemistry 10 Volume Set, 2Nd Edition R
Encyclopedia of Inorganic Chemistry 10 Volume Set, 2nd Edition R. Bruce King (Editor) ISBN: 0-470-86078-2 Table of Contents: Actinides: Organometallic Chemistry. Activated Complex. Alkali Metals: Organometallic Chemistry. Alkalides. Alkaline Earth Metals: Organometallic Chemistry. Alkane Carbon–Hydrogen Bond Activation. Alkene Complexes. Allyl Complexes. Aluminum: Organometallic Chemistry. Ambidentate Ligand. Ammonolysis. Ancillary Ligand. Antimony: Organometallic Chemistry. Antioxidant. Arsenic: Organoarsenic Chemistry. Arsine & As-donor Ligands. Asymmetric Unit. Beryllium & Magnesium: Organometallic. Chemistry. Beta Sheet. Biomineralization. Biosynthesis. Bismuth: Organometallic Chemistry. Bite Angle. σ -Bond Metathesis. Borates: Solid-state Chemistry. Borazine. Born–Haber Cycle. Boron: Inorganic Chemistry. Boron: Metallacarbaboranes. Boron: Metalloboranes. Boron: Organoboranes. Boron: Polyhedral Carboranes. Borosilicate Glass. Cadmium: Organometallic Chemistry. Cage Effect. Calixarenes. Carbides: Transition Metal Solid-state Chemistry. Carbocation. Carbon: Fullerenes. Carbon: Inorganic Chemistry. Carbon: Nanotubes. Carbonyl Complexes of the Transition Metals. Carbonyl Compound. Carborane. Ceramic Material. Chalcogens. Chlorophyll. CNDO Calculations. Cobalt: Inorganic & Coordination Chemistry. Cobalt: Organometallic Chemistry. Cobaltocene. Coordination Complexes. Coordination & Organometallic Chemistry: Principles. Coordination Theory. Copper: Hemocyanin/Tyrosinase Models. Copper: Inorganic & Coordination Chemistry. Copper: Organometallic -
Part I. Inversion of Secondary Cyclic Grignard Reagents
This dissertation has been , 69-11,692 microfilmed exactly as received PECHHOLD, Engelbert, 1933- STUDIES OF THE BEHAVIOR AND GENERATION OF GARB ANIONS: PART I. INVERSION OF SECONDARY CYCLIC GRIGNARD REAGENTS. PART II. FRAGMENTATION OF AZOFORMATE SALTS AND ACYLAZO COMPOUNDS WITH BASES. The Ohio State University, Ph.D., 1968 Chemistry, organic University Microfilms, Inc., Ann Arbor, Michigan ©Copyright "by- Engelbert Pechhold 1969 STUDIES OF THE BEHAVIOR MD GENERATION OF CARBANIONS PART I. INVERSION OF SECONDARY CYCLIC GRIGNARD REAGENTS PART II. FRAGMENTATION OF AZOFORMATE SADIS AND ACYLAZO COMPOUNDS WITH BASES DISSERTATION Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University By Engelbert Pechhold * # # * * # The Ohio State University 1968 Approved by •pV-gpa.-t— Adviser Department of Chemistry DEDICATION To my wife, Ingrid, and my parents, whose love, understanding, and encouragement have made this venture possible. ii ACKNOWLEDaEMElWS I -wish to express my deepest appreciation to Professor Gideon Fraenkel for suggestinf^ this problem, and for his guidance and encouragement throughout the course of this research. His assistance in the preparation of this dissertation is gratefully acknowledged. It is an understatement to say that without his un usual courage of conviction and high standards for academic perfor mance, this work could not have come into being. I owe special debt of gratitude to my colleagues for many suimtü-ating discussions of chemical matters and otherwise. In particular, I wish to express my gratitute to Dr. Don Dix, Dr. Dave Mams, and James Morton, who gave me much insight in ny research. -
Theoretical Insight Into the Transmetalation of MOF-5 Lattices
Article pubs.acs.org/cm When the Solvent Locks the Cage: Theoretical Insight into the Transmetalation of MOF‑5 Lattices and Its Kinetic Limitations ,† ‡ †,§ ‡ † Luca Bellarosa,* Carl K. Brozek, Max García-Melchor, Mircea Dinca,̆and Nuriá Lopeź † Institute of Chemical Research of Catalonia, ICIQ, Av. Països Catalans 16, 43007 Tarragona, Spain ‡ Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States § SUNCAT Center for Interface Science and Catalysis, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States *S Supporting Information ABSTRACT: Transmetalation is an innovative postsynthetic strategy for tailoring the properties of metal−organic frameworks (MOFs), allowing stable unprecedented metal coordination environments. Although the experimental synthetic protocol is well- established, the underlying mechanism for transmetalation is still unknown. In this work, we propose two different solvent-mediated reaction paths for the Ni transmetalation in Zn- MOF-5 lattices through density functional theory simulations. In both mechanisms, the bond strength between the exchanged metal and the solvent is the key descriptor that controls the degree of transmetalation. We also show that the role of the solvent in this process is twofold: it initially promotes Zn exchange, but if the metal−solvent bond is too strong, it blocks the second transmetalation cycle by restricting the lattice flexibility. The competition between these two effects leads the degree of incorporation of metal into MOF-5 to display a volcano-type dependence with respect to the metal−solvent bond strength for different transition metal ions. ■ INTRODUCTION PSIM.26 Nevertheless, the dependence on the ligand field was The easiness with which metal−organic frameworks (MOFs)1 found to be opposite for Ni inserting into MOF-5 and Co into MFU-4l.