2.4 Department of Organometallic Chemistry
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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. -
Socit Chimique De France 2014 Prize Winners
Angewandte. Angewandte News Chemie Socit Chimique de France 2014 Prize Nazario Martn (Universidad Complutense de Winners Madrid) is the winner of the Prix franco-espagnol Awarded … Miguel Cataln–Paul Sabatier. Martn was featured The Socit Chimique de France has announced its here when he was awarded the 2012 EuCheMS 2014 prize winners. We congratulate all the awar- Lectureship.[4a] Martn is on the International dees and feature our authors and referees here. Advisory Boards of Chemistry—An Asian Journal, Max Malacria (Institut de Chimie des Substan- ChemPlusChem, and ChemSusChem. His report on ces Naturelles; ICSN) is the winner of the Prix modified single-wall nanotubes was recently fea- Joseph Achille Le Bel, which is awarded to tured on the cover of Chemistry—A European recognize internationally recognized research. Mal- Journal.[4b] acria studied at the Universit Aix-Marseille III, Michael Holzinger (Universit Joseph Four- where he completed his PhD under the supervision nier, Grenoble 1; UJF) is the winner of the Prix M. Malacria of Marcel Bertrand in 1974. From 1974–1981, he jeune chercheur from the Analytical Chemistry was matre-assistant with Jacques Gore at the Division. Holzinger carried out his PhD at the Universit Claude Bernard Lyon 1 (UCBL), and Friedrich-Alexander-Universitt Erlangen-Nrn- from 1981–1983, he carried out postdoctoral berg. After postdoctoral research at the Universit research with K. Peter C. Vollhardt at the Univer- Montpellier 2 (UM2) and the Max Planck Institute sity of California, Berkeley. He returned to the for Solid-State Research, and working at Robert UCBL as matre de conferences in 1983, and was Bosch, he joined Serge Cosniers group at the UJF made professor at the Universit Pierre et Marie as a CNRS charg de recherche. -
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. -
Pearson-CV-15.Pdf
A. J. Pearson/C.V. January 2016 Curriculum Vitae Anthony J. Pearson Academic Rank: Rudolph & Susan Rense Professor of Chemistry Birthplace: Kingswinford, England. Citizenship: British; U.S. Naturalized Citizen. Education: University of Leeds, England, B.Sc. Hons. Class 1, 1971, Chemistry. Aston University, England, Ph.D., 1974, Organic Chemistry. Awards & Honors: Akroyd Scholarship (1969), Whytlaw-Gray Prize for Chemistry (1971), and Dawson Prize for Physical Chemistry (1971), University of Leeds. Sir Gilbert Morgan Medal (1973), Society for Chemical Industry, U.K. Science and Engineering Research Council (U.K.) Advanced Fellowship (1977-82). Sigma Xi Research Award (1984), Case Western Reserve University. John S. Diekhoff Award for Distinguished Graduate Teaching (1994), Case Western Reserve University. Visiting Scientist, Chemistry Research Promotion Center, Taipei, Taiwan, R.O.C., May 1990. Visiting Professor, University of Auckland, New Zealand, July/August, 1995. Chairman-Elect, American Chemical Society, Cleveland Section, 1999. Chairman, 2000. Finalist (one of three) for Northern Ohio Live 2001 Award of Achievement in Architecture, with R. Bostwick, N. Distad, K. Kutina, and N. Rushforth, for design of Agnar Pytte Science Center at CWRU. Case Alumni Association, Recognition of Meritorious Service, 2003. Experience: 1963-66 Chemist. Industrial research and analytical laboratories. Albright & Wilson; British Steel; West Midlands Gas Board. Semi-professional musician. 1974-77 Postdoctoral Research Fellow, with Arthur J. Birch. Research School of Chemistry, Australian National University, Canberra, Australia. 1977-82 SERC Advanced Fellow. Cambridge University Chemical Laboratory. 1978-81 Pauline Merz Official Fellow and Lecturer in Chemistry. Girton College, Cambridge University. 1979-81 Tutor. Girton College, Cambridge University. 1982-84 Associate Professor of Chemistry. -
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 -
A Nobel Synthesis
MILESTONES IN CHEMISTRY Ian Grayson A nobel synthesis IAN GRAYSON Evonik Degussa GmbH, Rodenbacher Chaussee 4, Hanau-Wolfgang, 63457, Germany he first Nobel Prize for chemistry was because it is a scientific challenge, as he awarded in 1901 (to Jacobus van’t Hoff). described in his Nobel lecture: “The synthesis T Up to 2010, the chemistry prize has been of brazilin would have no industrial value; awarded 102 times, to 160 laureates, of whom its biological importance is problematical, only four have been women (1). The most but it is worth while to attempt it for the prominent area for awarding the Nobel Prize sufficient reason that we have no idea how for chemistry has been in organic chemistry, in to accomplish the task” (4). which the Nobel committee includes natural Continuing the list of Nobel Laureates in products, synthesis, catalysis, and polymers. organic synthesis we arrive next at R. B. This amounts to 24 of the prizes. Reading the Woodward. Considered by many the greatest achievements of the earlier organic chemists organic chemist of the 20th century, he who were recipients of the prize, we see that devised syntheses of numerous natural they were drawn to synthesis by the structural Alfred Nobel, 1833-1896 products, including lysergic acid, quinine, analysis and characterisation of natural cortisone and strychnine (Figure 1). 6 compounds. In order to prove the structure conclusively, some In collaboration with Albert Eschenmoser, he achieved the synthesis, even if only a partial synthesis, had to be attempted. It is synthesis of vitamin B12, a mammoth task involving nearly 100 impressive to read of some of the structures which were deduced students and post-docs over many years. -
04. M.SC Chemistry
DEPARTMENT OF CHEMISTRY ANNA UNIVERSITY, CHENNAI VISION The Department of Chemistry at Anna University shall strive towards attaining world class status and recognition by producing students with sound knowledge, professional skills, high levels of integrity and ethical values. The Department shall provide an outstanding ambience for teaching, research and consultancy.The Department shall perform frontier research and create knowledge base in theoretical and appliedchemistry, polymeric and catalytic materials, fuel and energy related processes and materials, environmental chemistry and other transdisciplinary areas of technological importance. MISSION The Department of Chemistry, Anna University shall contribute to the educational, economic and social development: By producing postgraduates and Doctorates who are equipped with thorough knowledge in Chemistry, analytical thinking, practical skills and ethics. By inspiring the students to be creative thinkers, inspirational role models and citizens with environmental and social consciousness. By introducing high quality academic and research programmes in Chemistry and enabling interaction with experts from around the world in the fields of Chemistry. By ensuring a supportive ambience in the Department with dynamic leadership and growth opportunities to meet the needs of the students, faculty and staff. By promoting the development of technologically and socially relevant processes and products in the fields of catalysis, polymers, corrosion resistance coatings and energy conversion through academic and sponsored research, in collaboration with global research groups. By sharing the intellectual resources and infrastructural facilities of the Department of Chemistry among the academic fraternity of the University campus and other Institutions, among the industrial research groups, funding agencies and the Government. By facilitating collaborative partnership with industries and other institutions and catalyseinnovation, transfer of technology and commercialization towards fulfilling societal developments. -
Lithium Transport in Crown Ether Polymers
Durham E-Theses Lithium transport in crown ether polymers Collie, Luke E. How to cite: Collie, Luke E. (1995) Lithium transport in crown ether polymers, Durham theses, Durham University. Available at Durham E-Theses Online: http://etheses.dur.ac.uk/5196/ Use policy The full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that: • a full bibliographic reference is made to the original source • a link is made to the metadata record in Durham E-Theses • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders. Please consult the full Durham E-Theses policy for further details. Academic Support Oce, Durham University, University Oce, Old Elvet, Durham DH1 3HP e-mail: [email protected] Tel: +44 0191 334 6107 http://etheses.dur.ac.uk Lithium Transport in Crown Ether Polymers Luke E. Collie BSc. (Hons.) University of Durham Department of Chemistry The copyright of this thesis rests with the author. No quotation from it should be published without his prior written consent and information derived from it should be acknowledged. A Thesis submitted for the degree of Doctor of Philosophy October 1995 1 6 JAN 1996 Statement of Copyright The copyright of this thesis rests with the author. No quotation from it should be published without his prior written consent and information derived from it should be acknowledged.