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4-Dimethylamino Pyridine (Dmap) Catalyst with Fluxional Chirality
4-DIMETHYLAMINO PYRIDINE (DMAP) CATALYST WITH FLUXIONAL CHIRALITY: SYNTHESIS AND APPLICATIONS A Dissertation Submitted to the Graduate Faculty of the North Dakota State University of Agriculture and Applied Science By Gaoyuan Ma In Partial Fulfillment of the Requirements for the Degree of DOCTOR OF PHILOSOPHY Major Department: Chemistry and Biochemistry November 2015 Fargo, North Dakota North Dakota State University Graduate School Title 4-Dimethylamino Pyridine (DMAP) Catalyst with Fluxional Chirality: Synthesis and Applications By Gaoyuan Ma The Supervisory Committee certifies that this disquisition complies with North Dakota State University’s regulations and meets the accepted standards for the degree of DOCTOR OF PHILOSOPHY SUPERVISORY COMMITTEE: Prof. Mukund P. Sibi Chair Prof. Gregory R. Cook Prof. Pinjing Zhao Prof. Dean C. Webster Approved: 11/30/2015 Prof. Gregory R. Cook Date Department Chair ABSTRACT Organocatalysis using small organic molecules to catalyze organic transformations, has emerged as a powerful synthetic tool that is complementary to metal-catalyzed transformations and remarkably promote stereoselective synthesis. Our group has designed useful templates, ligands, and additives that use fluxional groups to control and/or enhance stereoselectivity in a variety of asymmetric transformations. A key feature of this strategy is that the size of the fluxional substituent can be varied readily. As an extension of this strategy we became interested in developing efficient and broadly applicable and adjustable 4-dimethylaminopyridine (DMAP) organocatalysts. In our design, we surmised that a fluxional group would be effective in relaying stereochemical information from the fixed chiral center to the catalytic center of DMAP. Presented herein the synthesis of novel fluxionally chiral DMAP catalysts and their application in the acylative kinetic resolution of secondary alcohols and axially chiral biaryls, dynamic kinetic resolution of chiral biaryls with low rotation barriers and allylic substitution reactions. -
Design and Synthesis of Chiral Ligands and Their Applications in Transition
The Pennsylvania State University The Graduate School Department of Chemistry DESIGN AND SYNTHESIS OF CHIRAL LIGANDS AND THEIR APPLICATIONS IN TRANSITION METAL-CATALYZED ASYMMETRIC REACTIONS A Dissertation in Chemistry by Wei Li 2012 Wei Li Submitted in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy May 2012 The dissertation of Wei Li was reviewed and approved* by the following: Gong Chen Assistant Professor of Chemistry Dissertation Advisor Chair of Committee Tom Mallouk Evan Pugh Professor of Material Chemistry and Physics Alex Radosevich Assistant Professor of Chemistry Qing Wang Associate Professor of Material Science and Engineering Xumu Zhang Professor of Chemistry Special Member Barbara J. Garrison Shapiro Professor of Chemistry Head of the Department of Chemistry *Signatures are on file in the Graduate School iii ABSTRACT Transition metal catalyzed reactions are among the most powerful and direct approaches for the synthesis of organic molecules. During the past several decades, phosphorous-containing ligands have been extensively studied in transition metal - catalyzed transformations particularly asymmetric hydrogenations. Development of new chiral ligands and efficient catalyst systems for various prochiral unsaturated substrates in asymmetric hydrogenations are the focus of this dissertation. An important family of atropisomeric biaryl bisphosphine ligands, C3*-TunePhos and related bisaminophosphines have been designed and synthesized. The Ru catalysts of the highly modular C3*-TunePhos have been proved to be highly efficient (up to 99.8% ee, up to 1,000,000 TON) for practical asymmetric hydrogenations of a wide range of unfunctionalized ketones as well as α-, β- keto esters and N-2-substituted allylphthalimides. The synthetic utility of bisaminophosphine ligands was studied for rhodium-catalyzed asymmetric hydrogenations of α-dehydroamino acid esters, affording up to 98% ee’s. -
Synthesis and Application of Chiral Arabox Ligands for Asymmetric Catalysis
Provided by the author(s) and NUI Galway in accordance with publisher policies. Please cite the published version when available. Title Synthesis and Application of Chiral AraBOX ligands for Asymmetric Catalysis Author(s) Kellehan, David Publication Date 2012-11-28 Item record http://hdl.handle.net/10379/3405 Downloaded 2021-09-25T11:23:55Z Some rights reserved. For more information, please see the item record link above. Synthesis and Application of Chiral AraBOX ligands for Asymmetric Catalysis David Kellehan, B.Sc. (Hons.) Thesis presented for the Ph.D. Degree of the National University of Ireland, Galway School of Chemistry National University of Ireland, Galway September 2012 Head of School: Professor Paul V. Murphy Supervisor: Dr. Patrick O’Leary To Mom and Dad Contents i Acknowledgements iv Abbreviations v Abstract ix Chapter 1: Introduction 1 1.1 Asymmetric synthesis 2 1.1.1 Chiral pool synthesis 3 1.1.2 Resolution 4 1.2 Chiral auxiliaries 6 1.2.1 N-tert-butylsulfinamide 8 1.3 Catalysis 15 1.4 Asymmetric catalysis 15 1.4.1 Asymmetric transition metal catalysis 16 1.5 Bisoxazoline ligands 16 1.5.1 Structure 17 1.5.2 Naming of bisoxazolines 18 1.5.3 Synthesis of bisoxazolines 18 1.5.4 Metal bisoxazoline complexes 25 1.5.5 BOX ligands with secondary binding site 27 1.6 Asymmetric reactions using BOX ligands 30 1.6.1 Diels Alder reaction 30 i 1.6.2 Allylic Alkylation reaction 37 1.6.3 Ene reaction 41 1.6.4 Cyclopropanation reaction 44 References 51 Chapter 2: Results and Discussion 56 2.1 Introduction 57 2.2 Synthesis of 4,4'-bisoxazoline -
And Intermolecular Cyclopropanation by Co(II)- Based Metalloradical Catalysis Xue Xu University of South Florida, [email protected]
University of South Florida Scholar Commons Graduate Theses and Dissertations Graduate School January 2012 Asymmetric Intra- and Intermolecular Cyclopropanation by Co(II)- Based Metalloradical Catalysis Xue Xu University of South Florida, [email protected] Follow this and additional works at: http://scholarcommons.usf.edu/etd Part of the American Studies Commons, and the Organic Chemistry Commons Scholar Commons Citation Xu, Xue, "Asymmetric Intra- and Intermolecular Cyclopropanation by Co(II)- Based Metalloradical Catalysis" (2012). Graduate Theses and Dissertations. http://scholarcommons.usf.edu/etd/4262 This Dissertation is brought to you for free and open access by the Graduate School at Scholar Commons. It has been accepted for inclusion in Graduate Theses and Dissertations by an authorized administrator of Scholar Commons. For more information, please contact [email protected]. Asymmetric Intra- and Intermolecular Cyclopropanation by Co(II)- Based Metalloradical Catalysis by Xue(Snow) Xu A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy Department of Chemistry College of Arts and Sciences University of South Florida Major Professor: X. Peter Zhang, Ph.D. Jon Antilla, Ph.D. Mark L. McLaughlin, Ph.D. Wayne Guida, Ph.D. Date of Defense: June 20th, 2012 Keywords: cobalt, porphyrin, catalysis, cyclopropanation, carbene, diazo Copyright © 2012, Xue Xu DEDICATION I dedicate this dissertation to my parents and my husband, without their caring support, it would not have been possible. ACKNOWLEGEMENTS I need to begin with thanking Dr. Peter Zhang for his continuous guidance and support over the last 5 and half years. Especially for encouraging me to achieving my potential as a researcher and setting an example of dedication to science that is admirable. -
1 Introduction Asymmetric 1,3-Dipolar Cycloadditions Of
UCC Library and UCC researchers have made this item openly available. Please let us know how this has helped you. Thanks! Title Asymmetric 1,3-dipolar cycloadditions of acrylamides Author(s) Kissane, Marie; Maguire, Anita R. Publication date 2009 Original citation KISSANE, M. & MAGUIRE, A. R. 2010. Asymmetric 1,3-dipolar cycloadditions of acrylamides. Chemical Society Reviews, 39, 845-883. doi:10.1039/B909358N Type of publication Review Link to publisher's http://pubs.rsc.org/en/content/articlelanding/2010/cs/b909358n version http://dx.doi.org/10.1039/B909358N Access to the full text of the published version may require a subscription. Rights ©2010, The Authors. Exclusive licence to publish RSC Publishing. Item downloaded http://hdl.handle.net/10468/593 from Downloaded on 2021-10-06T13:25:14Z 1 Introduction Asymmetric 1,3-Dipolar Cycloadditions of Acrylamides Marie Kissanea and Anita R. Maguireb* a Department of Chemistry, Analytical and Biological Chemistry Research Facility, University College Cork, Cork, Ireland. bDepartment of Chemistry & School of Pharmacy, Analytical and Biological Chemistry Research Facility, University College Cork, Cork, Ireland. *Corresponding author. Tel.: +353 21 4901693; fax: +353 21 4274097. E-mail: [email protected]. Contents 1 Introduction ........................................................................................................................................................ 1 1.1 1,3-Dipolar cycloadditions .................................................................................................................... -
The Pyrolysis of Organic Esters Dissertation
THE PYROLYSIS OF ORGANIC ESTERS DISSERTATION Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University RICHARD JUI-FU LEE, B.S y l f .■) ®rV'«\ a.i @@ :&f a■ ' Adviser * Department of Chemistry -i- ACKMOWLEDGMEMT My sincere and profound thanks to Dr. Christo pher L. Wilson for the suggestion of the problem and his inspiring guidance throughout the research. My gratitude to the B. F. Goodrich Company, whose Research Fellowship I held for the entire span of this work. Finally, but not least, my deepest appreciation to Mr. Daniel Loughran for his ever cooperative assistance in making the infra-red analyses. -ii- TABLE OF CONTENTS Page I. INTRODUCTION AND STATEMENT OF PROBLEM 1 II. HISTORICAL INTRODUCTION........ ........... 5 1. Pyrolysis of Organic Compounds........ 5 A. Berthelot's Theory......... 5 B . Haber' s Rule ........................ 6 C. Rule of Least Molecular Deformation........................ 7 D. Bredt's Rule........................ 8 E. Blanc’s Rule................ 8 F. Nef's Theory......................... 9 2. Theory of Pyrolysis of Esters....... 10 A. Bilger and Hibbert's Mechanism.... 11 B. Hurd's "Hydrogen Bridge" Cyclic Mechanism....................... 13 C. Ritchie's Dual Reactions........... 16 D. Htickel's Concept (Tsugaev Reaction) 19 E. Alexander's Cis-Elimination Studies 20 F. Kinetics on the Pyrolysis of Esters 22 G. Some Contributions from the Kinetic Study of Dehydrochlorination of Chloroparaffins ...... 24 3. The Cyclic Transition State in Other Processes........... 32 A. General Considerations.............. 32 B. The Concept of O'Connor and Nace... 34 C. The Pyrolysis of Sulfites.......... 37 iii £a^e III. -
Acetaldehyde 16.05.2020.Pdf
Acetaldehyde Acetaldehyde (systematic name ethanal) is an organic chemical compound with the formula CH3CHO, sometimes abbreviated by chemists as MeCHO (Me = methyl). It is one of the most important aldehydes, occurring widely in nature and being produced on a large scale in industry. Acetaldehyde occurs naturally in coffee, bread, and ripe fruit, and is produced by plants. It is also produced by the partial oxidation of ethanol by the liver enzyme alcohol dehydrogenase and is a contributing cause of hangover after alcohol consumption. Pathways of exposure include air, water, land, or groundwater, as well as drink and smoke. Consumption of disulfiram inhibits acetaldehyde dehydrogenase, the enzyme responsible for the metabolism of acetaldehyde, thereby causing it to build up in the body. An aldehyde used as a starting material in the synthesis of 1-butanol (n-butyl alcohol), ethyl acetate, perfumes, flavourings, aniline dyes, plastics, synthetic rubber, and other chemical compounds. It has been manufactured by the hydration of acetylene and by the oxidation of ethanol (ethyl alcohol). Formula: C2H4O IUPAC ID: ethanal Boiling point: 20.2 °C Molar mass: 44.05 g/mol Density: 788 kg/m³ Melting point: -123.5 °C Preparation:- The main method of production is the oxidation of ethylene by the Wacker process, which involves oxidation of ethylene using a homogeneous palladium/copper system: 2 CH2=CH2 + O2 → 2 CH3CHO Smaller quantities can be prepared by the partial oxidation of ethanol in an exothermic reaction. This process typically is conducted over a silver catalyst at about 500–650 °C. 1 CH3CH2OH + ⁄2 O2 → CH3CHO + H2O This method is one of the oldest routes for the industrial preparation of acetaldehyde. -
Working Fluid Selection for Space-Based Two-Phase Heat Transport Systems
NBSIR 88-3812 Working Fluid Selection for Space-Based Two-Phase Heat Transport Systems Mark O. McLinden U.S. DEPARTMENT OF COMMERCE National Bureau of Standards Gaithersburg, MD 20899 May 1988 Issued August 1988 75 Years Stimulating America's Progress 1913-1988 Prepared for: National Aeronautics and Space Administration Goddard Space Flight Center NBSIR 88-3812 WORKING FLUID SELECTION FOR SPACE-BASED TWO-PHASE HEAT TRANSPORT SYSTEMS Mark O. McLinden U.S. DEPARTMENT OF COMMERCE National Bureau of Standards Gaithersburg, MD 20899 May 1988 Issued August 1988 Prepared for: National Aeronautics and Space Administration Goddard Space Flight Center U.S. DEPARTMENT OF COMMERCE, C. William Verity, Secretary NATIONAL BUREAU OF STANDARDS, Ernest Ambler, Director , ABSTRACT The working fluid for externally-mounted, space-based two-phase heat transport systems is considered. A sequence of screening criteria involving freezing and critical point temperatures and latent heat of vaporization and vapor density are applied to a data base of 860 fluids. The thermal performance of the 52 fluids which pass this preliminary screening are then ranked according to their impact on the weight of a reference system. Upon considering other non-thermal criteria ( f lagimability toxicity and chemical stability) a final set of 10 preferred fluids is obtained. The effects of variations in system parameters is investigated for these 10 fluids by means of a factorial design. i * . I . INTRODUCTION In order to remove the heat generated by electronics and other payloads on spacecraft some type of heat transport system is required. The heat generating equipment is typically attached to a 'cold plate'. -
Synthesis of Iron Carbonyl Complexes 64
FAKULTÄT FÜR CHEMIE Lehrstuhl für Strukturanalytik in der Katalyse The Synthesis, Characterization and Performance of Well-Defined Iron Carbonyl Catalysts Hüseyin Güler Vollständiger Abdruck der von der Fakultät für Chemie der Technischen Universität München zur Erlangung des akademischen Grades eines Doktors der Naturwissenschaften genehmigten Dissertation. Vorsitzender : Univ.-Prof. Dr. Klaus Köhler Prüfer der Dissertation: 1. Prof. Moniek Tromp, Ph.D. Univ. Amsterdam / Niederlande 2. Univ.-Prof. Dr. Thomas Brück Die Dissertation wurde am 28.05.2015 bei der Technischen Universität München eingereicht und durch die Fakultät für Chemie am 28.07.2015 angenommen. i THE SYNTHESIS, CHARACTERIZATION AND PERFORMANCE OF WELL-DEFINED IRON CARBONYL CATALYSTS HUSEYIN GULER Doctoral Thesis Technische Universität München May 2015 ii Hüseyin Güler: The Synthesis, Characterization and Performance of Well-Defined Iron Carbonyl Catalysts. © May 2015 iii ABSTRACT The synthesis of well-defined, uniform iron carbonyl based complexes incorporating disphoshine ligands was performed and their performance as homogeneous catalysts evaluated. The iron carbonyl diphosphine complexes were formed by reaction of Fe3(CO)12 and bidentate diphosphine ligands. Detailed characterizations as well as kinetic studies were performed to provide fundamental insights in the catalyst properties. These iron carbonyl complexes were examined as homogeneous catalysts in 2-propanol-based transfer hydrogenation of ketone. The influence of different reaction parameters on the catalytic performance was investigated. The scope and limitations of the described catalyst for the reduction of a series different ketones was shown. In most cases, high conversion and selectivity are obtained. Mechanistic and kinetic studies indicate a monohydride reaction pathway for the homogeneous iron catalyst. Iron carbonyls supported on γ-Al2O3 were obtained and their performance as heterogeneous catalysts evaluated. -
Chemfile Vol.6 No 8
2006 VOLUME 6 NUMBER 8 Privileged Ligands DUPHOS AND BPE PHOSPHOLANE LIGANDS DSM MONOPHOS™ FAMILY CHIRALQUEST PHOSPHINE LIGANDS SOLVIAS® FERROLceNYL-BASed LIGANDS (S)-MonoPhosTM: a powerful ligand for asymmetric synthesis. sigma-aldrich.com Introduction Chemists are continually searching for novel, efficient chiral transition metal catalysts to effect ever more difficult transformations. Highly effective asymmetric catalytic systems Vol. 6 No. 8 offer the possibility of synthesizing either desired enantiomer pure from simple achiral Aldrich Chemical Co., Inc. starting materials, with the chiral products then being directly employed in natural 1 Sigma-Aldrich Corporation product synthesis. Research groups have spent much well-earned effort in designing 6000 N. Teutonia Ave. high performance ligand platforms2 that exhibit the following general characteristics: Milwaukee, WI 53209, USA 1) the synthesis should be economically viable and allow for systematic variations in the architecture; 2) most (if not all) members of the ligand family should be readily produced from milligram to kilogram scale; and 3) the ligands should bind strongly to the metal center as well as generate a highly active and selective catalyst system. To Place Orders Chiral salens,3 bisoxazolines,4 tartrate ligands,5 and cinchona alkaloids6 represent the Telephone 800-325-3010 (USA) original “privileged ligands” classes that effect a wide variety of transformations under FAX 800-325-5052 (USA) exceptional enantiocontrol and with high productivity. Impressively, R&D groups -
Trisoxazolines: Synthesis and Application in Enantioselective Palladium- and Copper-Catalysed Reactions
Trisoxazolines: Synthesis and Application in enantioselective Palladium- and Copper-catalysed Reactions INAUGURAL-DISSERTATION zur Erlangung der Doktorwürde der Naturwissenschaftlich-Mathematischen Gesamtfakultät der Ruprecht-Karls-Universität Heidelberg vorgelegt von Diplom-Chemikerin Carole Foltz-César aus Beinheim, Frankreich durchgeführt am Anorganisch-Chemischen Institut der Ruprecht der Ruprecht-Karls-Universität Heidelberg und am Institut de Chimie der Université Louis Pasteur de Strasbourg Tag der mündlichen Prüfung: 30. November 2007 Trisoxazolines: Synthesis and Application in enantioselective Palladium- and Copper-catalysed Reactions Gutachter (Heidelberg): PD Dr. Markus Enders Prof. Dr. Günter Helmchen Gutachter (Strasbourg): Prof. Kilian Muñiz Acknowledgements Am ertser Stelle möchte ich Herrn Prof. L. H. Gade für die wertvolle Unterstützung und Diskussionsbereitschaft danken. Je remercie également Stéphane Bellemin-Laponnaz pour la confiance qu’il m’a accordée tout au long de ce travail de thèse. Malgré la distance, il a toujours su rester disponible pour partager son expérience et ses conseils. Herrn Prof. H. Wadepohl danke ich für die Durchführung und Auswertung der Röntgenstrukturanalysen und seine Diskussionsbereitschaft. Ich danke auch Herrn Dr. M. Enders für seine stete Hilfsbereitschaft. I am grateful to the Université Franco-Allemande and the European Doctoral College for funding. Irene Meyer und Stefan Schweizer möchte ich für ihre Mitarbeit im Rahmen eines Forschungspraktikums danken. Ein besonderer Dank geht an Beate, Dana und Lorenz für die grosse Hilfsbereitschaft und gute Zusammenarbeit. I would like to thank the members of Lab 2.11, to whom I am indebted for a friendly environment within which to work: Adeline, Felix and Nathanaëlle. I would also like to express my thanks to Ben for his endless help. -
TRANSITION-METAL-CATALYZED HYDROACYLATION Vy M. Dong, Kevin G. M. Kou, and Diane N. Le Department of Chemistry, University of Ca
TRANSITION-METAL-CATALYZED HYDROACYLATION Vy M. Dong, Kevin G. M. Kou, and Diane N. Le Department of Chemistry, University of California, Irvine, California 92697-2025, United States Vy M. Dong: [email protected] ACKNOWLEDGEMENTS Our work in this area has been supported by UC Irvine, the National Institutes of Health (GM105938), and NSERC. We also acknowledge Paul Feldman for his editorial assistance in compiling the chapter as well as Scott Denmark for the opportunity to contribute to Organic Reactions. INTRODUCTION Transition-metal catalysis has revolutionized the way natural products and medicinal targets are made. For example, asymmetric hydrogenation, olefin metathesis, and cross-coupling have evolved into indispensable tools for drug discovery. As a complement to these well-established strategies, the metal-catalyzed activation of C─H bonds is an increasingly valuable and attractive approach. In metal-catalyzed hydroacylation, an aldehyde C─H bond is oxidized to generate either a C─C bond or C─O bond, depending on the coupling partner used (e.g., alkene, alkyne, or carbonyl compound). This strategy represents an attractive, atom-economical approach for building both ketones and esters from aldehydes (Scheme 1). (1) To date, hydroacylation is most well-established for the preparation of five-membered rings, typically by rhodium catalysis. As the tether between the aldehyde and the unsaturated coupling partner becomes longer, decarbonylation becomes favored over hydroacylation. Similarly, the rate of decarbonylation is usually greater than the rate of hydroacylation in intermolecular reactions. The desired transformation is more favorable, however, when coodinating or directing groups are present on the substrate (Schemes 2 and 3).