Chapter 21 Organic Chemistry
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Part I: Carbonyl-Olefin Metathesis of Norbornene
Part I: Carbonyl-Olefin Metathesis of Norbornene Part II: Cyclopropenimine-Catalyzed Asymmetric Michael Reactions Zara Maxine Seibel Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Graduate School of Arts and Sciences COLUMBIA UNIVERSITY 2016 1 © 2016 Zara Maxine Seibel All Rights Reserved 2 ABSTRACT Part I: Carbonyl-Olefin Metathesis of Norbornene Part II: Cyclopropenimine-Catalyzed Asymmetric Michael Reactions Zara Maxine Seibel This thesis details progress towards the development of an organocatalytic carbonyl- olefin metathesis of norbornene. This transformation has not previously been done catalytically and has not been done in practical manner with stepwise or stoichiometric processes. Building on the previous work of the Lambert lab on the metathesis of cyclopropene and an aldehyde using a hydrazine catalyst, this work discusses efforts to expand to the less stained norbornene. Computational and experimental studies on the catalytic cycle are discussed, including detailed experimental work on how various factors affect the difficult cycloreversion step. The second portion of this thesis details the use of chiral cyclopropenimine bases as catalysts for asymmetric Michael reactions. The Lambert lab has previously developed chiral cyclopropenimine bases for glycine imine nucleophiles. The scope of these catalysts was expanded to include glycine imine derivatives in which the nitrogen atom was replaced with a carbon atom, and to include imines derived from other amino acids. i Table of Contents List of Abbreviations…………………………………………………………………………..iv Part I: Carbonyl-Olefin Metathesis…………………………………………………………… 1 Chapter 1 – Metathesis Reactions of Double Bonds………………………………………….. 1 Introduction………………………………………………………………………………. 1 Olefin Metathesis………………………………………………………………………… 2 Wittig Reaction…………………………………………………………………………... 6 Tebbe Olefination………………………………………………………………………... 9 Carbonyl-Olefin Metathesis……………………………………………………………. -
Chapter 21 the Chemistry of Carboxylic Acid Derivatives
Instructor Supplemental Solutions to Problems © 2010 Roberts and Company Publishers Chapter 21 The Chemistry of Carboxylic Acid Derivatives Solutions to In-Text Problems 21.1 (b) (d) (e) (h) 21.2 (a) butanenitrile (common: butyronitrile) (c) isopentyl 3-methylbutanoate (common: isoamyl isovalerate) The isoamyl group is the same as an isopentyl or 3-methylbutyl group: (d) N,N-dimethylbenzamide 21.3 The E and Z conformations of N-acetylproline: 21.5 As shown by the data above the problem, a carboxylic acid has a higher boiling point than an ester because it can both donate and accept hydrogen bonds within its liquid state; hydrogen bonding does not occur in the ester. Consequently, pentanoic acid (valeric acid) has a higher boiling point than methyl butanoate. Here are the actual data: INSTRUCTOR SUPPLEMENTAL SOLUTIONS TO PROBLEMS • CHAPTER 21 2 21.7 (a) The carbonyl absorption of the ester occurs at higher frequency, and only the carboxylic acid has the characteristic strong, broad O—H stretching absorption in 2400–3600 cm–1 region. (d) In N-methylpropanamide, the N-methyl group is a doublet at about d 3. N-Ethylacetamide has no doublet resonances. In N-methylpropanamide, the a-protons are a quartet near d 2.5. In N-ethylacetamide, the a- protons are a singlet at d 2. The NMR spectrum of N-methylpropanamide has no singlets. 21.9 (a) The first ester is more basic because its conjugate acid is stabilized not only by resonance interaction with the ester oxygen, but also by resonance interaction with the double bond; that is, the conjugate acid of the first ester has one more important resonance structure than the conjugate acid of the second. -
Metabolic-Hydroxy and Carboxy Functionalization of Alkyl Moieties in Drug Molecules: Prediction of Structure Influence and Pharmacologic Activity
molecules Review Metabolic-Hydroxy and Carboxy Functionalization of Alkyl Moieties in Drug Molecules: Prediction of Structure Influence and Pharmacologic Activity Babiker M. El-Haj 1,* and Samrein B.M. Ahmed 2 1 Department of Pharmaceutical Sciences, College of Pharmacy and Health Sciences, University of Science and Technology of Fujairah, Fufairah 00971, UAE 2 College of Medicine, Sharjah Institute for Medical Research, University of Sharjah, Sharjah 00971, UAE; [email protected] * Correspondence: [email protected] Received: 6 February 2020; Accepted: 7 April 2020; Published: 22 April 2020 Abstract: Alkyl moieties—open chain or cyclic, linear, or branched—are common in drug molecules. The hydrophobicity of alkyl moieties in drug molecules is modified by metabolic hydroxy functionalization via free-radical intermediates to give primary, secondary, or tertiary alcohols depending on the class of the substrate carbon. The hydroxymethyl groups resulting from the functionalization of methyl groups are mostly oxidized further to carboxyl groups to give carboxy metabolites. As observed from the surveyed cases in this review, hydroxy functionalization leads to loss, attenuation, or retention of pharmacologic activity with respect to the parent drug. On the other hand, carboxy functionalization leads to a loss of activity with the exception of only a few cases in which activity is retained. The exceptions are those groups in which the carboxy functionalization occurs at a position distant from a well-defined primary pharmacophore. Some hydroxy metabolites, which are equiactive with their parent drugs, have been developed into ester prodrugs while carboxy metabolites, which are equiactive to their parent drugs, have been developed into drugs as per se. -
Catalytic Pyrolysis of Plastic Wastes for the Production of Liquid Fuels for Engines
Electronic Supplementary Material (ESI) for RSC Advances. This journal is © The Royal Society of Chemistry 2019 Supporting information for: Catalytic pyrolysis of plastic wastes for the production of liquid fuels for engines Supattra Budsaereechaia, Andrew J. Huntb and Yuvarat Ngernyen*a aDepartment of Chemical Engineering, Faculty of Engineering, Khon Kaen University, Khon Kaen, 40002, Thailand. E-mail:[email protected] bMaterials Chemistry Research Center, Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Khon Kaen University, Khon Kaen, 40002, Thailand Fig. S1 The process for pelletization of catalyst PS PS+bentonite PP ) t e PP+bentonite s f f o % ( LDPE e c n a t t LDPE+bentonite s i m s n HDPE a r T HDPE+bentonite Gasohol 91 Diesel 4000 3500 3000 2500 2000 1500 1000 500 Wavenumber (cm-1) Fig. S2 FTIR spectra of oil from pyrolysis of plastic waste type. Table S1 Compounds in oils (%Area) from the pyrolysis of plastic wastes as detected by GCMS analysis PS PP LDPE HDPE Gasohol 91 Diesel Compound NC C Compound NC C Compound NC C Compound NC C 1- 0 0.15 Pentane 1.13 1.29 n-Hexane 0.71 0.73 n-Hexane 0.65 0.64 Butane, 2- Octane : 0.32 Tetradecene methyl- : 2.60 Toluene 7.93 7.56 Cyclohexane 2.28 2.51 1-Hexene 1.05 1.10 1-Hexene 1.15 1.16 Pentane : 1.95 Nonane : 0.83 Ethylbenzen 15.07 11.29 Heptane, 4- 1.81 1.68 Heptane 1.26 1.35 Heptane 1.22 1.23 Butane, 2,2- Decane : 1.34 e methyl- dimethyl- : 0.47 1-Tridecene 0 0.14 2,2-Dimethyl- 0.63 0 1-Heptene 1.37 1.46 1-Heptene 1.32 1.35 Pentane, -
Butenes Separation, Supp. A
PROCESS ECONOMICS PROGRAM SRI INTERNATIONAL Menlo Park, California 94025 Abstract Process Economics Program Report No. 71A BUTTLENES (October 1982) Demand is fast increasing for lsobutylene, especially that used in manufacturing methyl tertiary-butyl ether, and for high purity butene-1 to use as a copolymer in linear low density polyethylene. Because of their wide availability, mixed butane-butylene streams from oleflns plants and petroleum refineries are being increasingly fed to plants to separate butylenes for use in chemicals. This first supplement to Report No. 71 updates demand projections, production capacities, and separation techniques for high purity butene-1 and lsobutylene. The processes that are now available for separating and purifying both butene-1 and lsobutylene from mixed butyl- ene streams are evaluated and compared. Other procedures for obtaining butylenes, such as dehydrogenatlon, lsomerleatlon, and disproportion&ion, are not updated in this report. PEP’81 JLC Report No. 71A - BUTYLENES SUPPLEMENT A by JOHN L. CHADWICK I I October 1982 f-F0 0 A private report by the m PROCESS ECONOMICS PROGRAM 0 Menlo Park, California 94025 0 For detailed marketing data and information, the reader is referred to one of the SRI programs specializing in marketing research. The CHEMICALECONOMICS HANDBOOK Program covers most major chemicals and chemical products produced in the United States and the WORLDPETROCHEMICALS Program covers major hkdrocarbons and their derivatives on a worldwide basis. In addition, the SRI DIRECTORYOF CHEMICALPRODUCERS services provide detailed lists of chemical producers by company, prod- uct, and plant for the United States and Western Europe. ii CONTENTS 1 INTRODUCTION . 1 2 SUMMARY . -
Organic Chemistry
Wisebridge Learning Systems Organic Chemistry Reaction Mechanisms Pocket-Book WLS www.wisebridgelearning.com © 2006 J S Wetzel LEARNING STRATEGIES CONTENTS ● The key to building intuition is to develop the habit ALKANES of asking how each particular mechanism reflects Thermal Cracking - Pyrolysis . 1 general principles. Look for the concepts behind Combustion . 1 the chemistry to make organic chemistry more co- Free Radical Halogenation. 2 herent and rewarding. ALKENES Electrophilic Addition of HX to Alkenes . 3 ● Acid Catalyzed Hydration of Alkenes . 4 Exothermic reactions tend to follow pathways Electrophilic Addition of Halogens to Alkenes . 5 where like charges can separate or where un- Halohydrin Formation . 6 like charges can come together. When reading Free Radical Addition of HX to Alkenes . 7 organic chemistry mechanisms, keep the elec- Catalytic Hydrogenation of Alkenes. 8 tronegativities of the elements and their valence Oxidation of Alkenes to Vicinal Diols. 9 electron configurations always in your mind. Try Oxidative Cleavage of Alkenes . 10 to nterpret electron movement in terms of energy Ozonolysis of Alkenes . 10 Allylic Halogenation . 11 to make the reactions easier to understand and Oxymercuration-Demercuration . 13 remember. Hydroboration of Alkenes . 14 ALKYNES ● For MCAT preparation, pay special attention to Electrophilic Addition of HX to Alkynes . 15 Hydration of Alkynes. 15 reactions where the product hinges on regio- Free Radical Addition of HX to Alkynes . 16 and stereo-selectivity and reactions involving Electrophilic Halogenation of Alkynes. 16 resonant intermediates, which are special favor- Hydroboration of Alkynes . 17 ites of the test-writers. Catalytic Hydrogenation of Alkynes. 17 Reduction of Alkynes with Alkali Metal/Ammonia . 18 Formation and Use of Acetylide Anion Nucleophiles . -
Introduction to Aromaticity
Introduction to Aromaticity Historical Timeline:1 Spotlight on Benzene:2 th • Early 19 century chemists derive benzene formula (C6H6) and molecular mass (78). • Carbon to hydrogen ratio of 1:1 suggests high reactivity and instability. • However, benzene is fairly inert and fails to undergo reactions that characterize normal alkenes. - Benzene remains inert at room temperature. - Benzene is more resistant to catalytic hydrogenation than other alkenes. Possible (but wrong) benzene structures:3 Dewar benzene Prismane Fulvene 2,4- Hexadiyne - Rearranges to benzene at - Rearranges to - Undergoes catalytic - Undergoes catalytic room temperature. Faraday’s benzene. hydrogenation easily. hydrogenation easily - Lots of ring strain. - Lots of ring strain. - Lots of ring strain. 1 Timeline is computer-generated, compiled with information from pg. 594 of Bruice, Organic Chemistry, 4th Edition, Ch. 15.2, and from Chemistry 14C Thinkbook by Dr. Steven Hardinger, Version 4, p. 26 2 Chemistry 14C Thinkbook, p. 26 3 Images of Dewar benzene, prismane, fulvene, and 2,4-Hexadiyne taken from Chemistry 14C Thinkbook, p. 26. Kekulé’s solution: - “snake bites its own tail” (4) Problems with Kekulé’s solution: • If Kekulé’s structure were to have two chloride substituents replacing two hydrogen atoms, there should be a pair of 1,2-dichlorobenzene isomers: one isomer with single bonds separating the Cl atoms, and another with double bonds separating the Cl atoms. • These isomers were never isolated or detected. • Rapid equilibrium proposed, where isomers interconvert so quickly that they cannot be isolated or detected. • Regardless, Kekulé’s structure has C=C’s and normal alkene reactions are still expected. - But the unusual stability of benzene still unexplained. -
Aldehydes and Ketones
12 Aldehydes and Ketones Ethanol from alcoholic beverages is first metabolized to acetaldehyde before being broken down further in the body. The reactivity of the carbonyl group of acetaldehyde allows it to bind to proteins in the body, the products of which lead to tissue damage and organ disease. Inset: A model of acetaldehyde. (Novastock/ Stock Connection/Glow Images) KEY QUESTIONS 12.1 What Are Aldehydes and Ketones? 12.8 What Is Keto–Enol Tautomerism? 12.2 How Are Aldehydes and Ketones Named? 12.9 How Are Aldehydes and Ketones Oxidized? 12.3 What Are the Physical Properties of Aldehydes 12.10 How Are Aldehydes and Ketones Reduced? and Ketones? 12.4 What Is the Most Common Reaction Theme of HOW TO Aldehydes and Ketones? 12.1 How to Predict the Product of a Grignard Reaction 12.5 What Are Grignard Reagents, and How Do They 12.2 How to Determine the Reactants Used to React with Aldehydes and Ketones? Synthesize a Hemiacetal or Acetal 12.6 What Are Hemiacetals and Acetals? 12.7 How Do Aldehydes and Ketones React with CHEMICAL CONNECTIONS Ammonia and Amines? 12A A Green Synthesis of Adipic Acid IN THIS AND several of the following chapters, we study the physical and chemical properties of compounds containing the carbonyl group, C O. Because this group is the functional group of aldehydes, ketones, and carboxylic acids and their derivatives, it is one of the most important functional groups in organic chemistry and in the chemistry of biological systems. The chemical properties of the carbonyl group are straightforward, and an understanding of its characteristic reaction themes leads very quickly to an understanding of a wide variety of organic reactions. -
Cyclobutane Derivatives in Drug Discovery
Cyclobutane Derivatives in Drug Discovery Overview Key Points Unlike larger and conformationally flexible cycloalkanes, Cyclobutane adopts a rigid cyclobutane and cyclopropane have rigid conformations. Due to the ring strain, cyclobutane adopts a rigid puckered puckered conformation Offer ing advantages on (~30°) conformation. This unique architecture bestowed potency, selectivity and certain cyclobutane-containing drugs with unique pharmacokinetic (PK) properties. When applied appropriately, cyclobutyl profile. scaffolds may offer advantages on potency, selectivity and pharmacokinetic (PK) profile. Bridging Molecules for Innovative Medicines 1 PharmaBlock designs and Cyclobutane-containing Drugs synthesizes over 1846 At least four cyclobutane-containing drugs are currently on the market. cyclobutanes, and 497 Chemotherapy carboplatin (Paraplatin, 1) for treating ovarian cancer was cyclobutane products are prepared to lower the strong nephrotoxicity associated with cisplatin. By in stock. CLICK HERE to replacing cisplatin’s two chlorine atoms with cyclobutane-1,1-dicarboxylic find detailed product acid, carboplatin (1) has a much lower nephrotoxicity than cisplatin. On information on webpage. the other hand, Schering-Plough/Merck’s hepatitis C virus (HCV) NS3/4A protease inhibitor boceprevir (Victrelis, 2) also contains a cyclobutane group in its P1 region. It is 3- and 19-fold more potent than the 1 corresponding cyclopropyl and cyclopentyl analogues, respectively. Androgen receptor (AR) antagonist apalutamide (Erleada, 4) for treating castration-resistant prostate cancer (CRPC) has a spirocyclic cyclobutane scaffold. It is in the same series as enzalutamide (Xtandi, 3) discovered by Jung’s group at UCLA in the 2000s. The cyclobutyl- (4) and cyclopentyl- derivative have activities comparable to the dimethyl analogue although the corresponding six-, seven-, and eight-membered rings are slightly less 2 active. -
Stereochemistry, Alkyl Halide Substitution (SN1 & SN2)
Chem 261 Assignment & Lecture Outline 3: Stereochemistry, Alkyl Halide Substitution (SN1 & SN2) Read Organic Chemistry, Solomons, Fryle & Snyder 12th Edition (Electronic) • Functional Group List – Learn to recognize – Please see Green Handout – also p 76 of text • Periodic Table – Inside Front Cover - know 1st 10 elements (up through Neon) • Relative Strength of Acids and Bases – Inside Front cover (reference only) • Chapter 5 – Stereochemistry • Chapter 6 –Ionic Reactions: Nucleophilic Substitution of Alkyl Halides Problems: Do Not turn in, answers available in "Study Guide Student Solutions Manual " Solomons, Fryle, Snyder • Chapter 5: 5.1 to 5.15; 5.18 to 5.21; 5.26; 5.28; 5.33a-d; 5.46 • Chapter 6: 6.1 to 6.5; 6.7 to 6.10; 6.13; 6.20; 6.26; 6.27 Lecture Outline # 3 I. Comparison of 2 Structures: Same Molecular Formula ? -> If Yes, Possibly Isomers or Identical Same Arrangement (Sequence) of Groups ? If No -> Structural Isomers If Yes -> Superposable? If Yes -> Identical Structures If No -> Stereoisomers Non-Superposable Mirror Images ? If NO -> Diastereomers If Yes -> Enantiomers II. Chirality and Stereoisomers A. The Concept of Chirality 1. Identification of chiral objects a) achiral = not chiral b) planes of symmetry within a molecule 2. Types of stereoisomers – enantiomers and diastereomers B. Location of stereogenic (chiral) centres – 4 different groups on tetrahedral atom 1. Enantiomers & diastereomers 2. Meso compounds - chiral centers with plane of symmetry within molecule 3. Molecules with more than one chiral centre 4. Recognition of chiral centers in complex molecules - cholesterol - 8 chiral centres Drawing the enantiomer of cholesterol and its potential 255 stereoisomers 5. -
Evaluated Gas Phase Basicities and Proton Affinities of Molecules; Heats of Formation of Protonated Molecules
Evaluated Gas Phase Basicities and Proton Affinities of Molecules; Heats of Formation of Protonated Molecules Cite as: Journal of Physical and Chemical Reference Data 13, 695 (1984); https://doi.org/10.1063/1.555719 Published Online: 15 October 2009 Sharon G. Lias, Joel F. Liebman, and Rhoda D. Levin ARTICLES YOU MAY BE INTERESTED IN Evaluated Gas Phase Basicities and Proton Affinities of Molecules: An Update Journal of Physical and Chemical Reference Data 27, 413 (1998); https:// doi.org/10.1063/1.556018 Density-functional thermochemistry. III. The role of exact exchange The Journal of Chemical Physics 98, 5648 (1993); https://doi.org/10.1063/1.464913 A consistent and accurate ab initio parametrization of density functional dispersion correction (DFT-D) for the 94 elements H-Pu The Journal of Chemical Physics 132, 154104 (2010); https://doi.org/10.1063/1.3382344 Journal of Physical and Chemical Reference Data 13, 695 (1984); https://doi.org/10.1063/1.555719 13, 695 © 1984 American Institute of Physics for the National Institute of Standards and Technology. Evaluated Gas Phase Basicities and Proton Affinities of Molecules; Heats of Formation of Protonated Molecules Sharon G. Lias Center for Chemical Physics, National Bureau of Standards, Gaithersburg, MD 20899 Joel F. Liebman Department of Chemistry, University of Maryland Baltimore County, Catonsville, MD 21228 and Rhoda D. Levin Center for Chemical Physics. National Bureau of Standards, Gaithersburg, MD 20899 The available data on gas phase basicities and proton affinities of molecules are compiled and evaluated. Tables giving the molecules ordered (1) according to proton affinity and (2) according to empirical formula, sorted alphabetically are provided. -
Isomer Distributions of Molecular Weight 247 and 273 Nitro-Pahs in Ambient Samples, NIST Diesel SRM, and from Radical-Initiated Chamber Reactions
Atmospheric Environment 55 (2012) 431e439 Contents lists available at SciVerse ScienceDirect Atmospheric Environment journal homepage: www.elsevier.com/locate/atmosenv Isomer distributions of molecular weight 247 and 273 nitro-PAHs in ambient samples, NIST diesel SRM, and from radical-initiated chamber reactions Kathryn Zimmermann a,1, Roger Atkinson a,1,2,3, Janet Arey a,1,2,*, Yuki Kojima b,4, Koji Inazu b,5 a Air Pollution Research Center, University of California, Riverside, CA 92521, USA b Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8502, Japan article info abstract Article history: Molecular weight (mw) 247 nitrofluoranthenes and nitropyrenes and mw 273 nitrotriphenylenes (NTPs), Received 27 December 2011 nitrobenz[a]anthracenes, and nitrochrysenes were quantified in ambient particles collected in Riverside, Received in revised form CA, Tokyo, Japan, and Mexico City, Mexico. 2-Nitrofluoranthene (2-NFL) was the most abundant nitro- 28 February 2012 polycyclic aromatic hydrocarbon (nitro-PAH) in Riverside and Mexico City, and the mw 273 nitro-PAHs Accepted 5 March 2012 were observed in lower concentrations. However, in Tokyo concentrations of 1- þ 2-NTP were more similar to that of 2-NFL. NIST SRM 1975 diesel extract standard reference material was also analyzed to Keywords: examine nitro-PAH isomer distributions, and 12-nitrobenz[a]anthracene was identified for the first time. Nitro-PAH fl Atmospheric reactions The atmospheric formation pathways of nitro-PAHs were studied from chamber reactions of uo- Ambient particles ranthene, pyrene, triphenylene, benz[a]anthracene, and chrysene with OH and NO3 radicals at room Nitrotriphenylenes temperature and atmospheric pressure, with the PAH concentrations being controlled by their vapor pressures.