DOCSLIB.ORG

Nomenclature of Carboxylic Acids • Select the Longest Carbon Chain Containing the Carboxyl Group

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text

Load more

Chapter 5 Carboxylic Acids and Esters Carboxylic Acids • Carboxylic acids are weak organic acids which Chapter 5 contain the carboxyl group (RCO2H): Carboxylic Acids and Esters O C O H O RCOOH RCO2H Chapter Objectives: O condensed ways of • Learn to recognize the carboxylic acid, ester, and related functional groups. RCOH writing the carboxyl • Learn the IUPAC system for naming carboxylic acids and esters. group a carboxylic acid C H • Learn the important physical properties of the carboxylic acids and esters. • Learn the major chemical reaction of carboxylic acids and esters, and learn how to O predict the products of ester synthesis and hydrolysis reactions. the carboxyl group • Learn some of the important properties of condensation polymers, especially the polyesters. Mr. Kevin A. Boudreaux • The tart flavor of sour-tasting foods is often caused Angelo State University CHEM 2353 Fundamentals of Organic Chemistry by the presence of carboxylic acids. Organic and Biochemistry for Today (Seager & Slabaugh) www.angelo.edu/faculty/kboudrea 2 Nomenclature of Carboxylic Acids • Select the longest carbon chain containing the carboxyl group. The -e ending of the parent alkane name is replaced by the suffix -oic acid. • The carboxyl carbon is always numbered “1” but the number is not included in the name. • Name the substituents attached to the chain in the Nomenclature of usual way. • Aromatic carboxylic acids (i.e., with a CO2H Carboxylic Acids directly connected to a benzene ring) are named after the parent compound, benzoic acid. O C OH 3 4 Benzoic acid Examples: Naming Carboxylic Acids Examples: Naming Carboxylic Acids • Name the following compounds: • Name the following compounds: O O O Br O HCOH CH3 COH COH CH3CHCH2 COH CH3CH2CHCH3 O O HO CCH2CH2CH3 CH3CH2 COH CH3 O CH3CHCH2 COH CH2CH2CH3 5 6 Chapter 5 Carboxylic Acids and Esters Examples: Naming Carboxylic Acids Examples: Naming Carboxylic Acids • Name the following compounds: • Name the following compounds: CH 3 CO H O 2 O CH O COH 3 COH CH C OH CH3CCH3 CH3 O Cl CH2CH2CHCH3 CH3 C OH 7 CH3CHCH3 8 More Complicated Acids Examples: Drawing Carboxylic Acids • For molecules with two carboxylic acid groups the • Draw structural formulas for the following molecules: carbon chain in between the two carboxyl groups – 2-methylpropanoic acid (including the carboxyl carbons) is used as the longest chain; the suffix -dioic acid is used. • For molecules with more than two carboxylic acid groups, the carboxyl groups are named as carboxylic – 2,2,5-trimethylhexanoic acid acid substituents. O O O O HOC C OH – 4,5-dimethyl-3-nitrooctanoic acid ethanedioic acid HO C CH2 CH CH2 C OH O O C OOH HO C CH2 C OH propane-1,2,3-tricarboxylic acid propanedioic acid 9 10 Examples: Drawing Carboxylic Acids • Draw structural formulas for the following molecules: – para-bromobenzoic acid – 2,4,6-trinitrobenzoic acid – 4-ethylpentanedioic acid (what’s wrong with this name?) 11 12 Chapter 5 Carboxylic Acids and Esters Physical Properties of Carboxylic Acids • Carboxylic acids hydrogen bond to themselves to form a dimer: O H O RC C R Physical Properties of O H O • Carboxylic acids also form hydrogen bonds to Carboxylic Acids water molecules: H H O O RC H O H O 13 14 H Physical Properties of Carboxylic Acids Physical Properties of Carboxylic Acids • Since carboxylic acids can form more than one set of • As the number of carbons in a carboxylic acid series hydrogen bonds, their boiling points are usually becomes greater, the boiling point increases and the higher than those of other molecules of the same solubility in water decreases. molecular weight (MW). • Many carboxylic acids that are liquids at room • Low-MW carboxylic acids are generally liquids at temperature have characteristically sharp or room temp. (often, they are somewhat oily); higher- unpleasant odors. MW carboxylic acids are generally waxy solids. – Ethanoic acid/acetic acid is the main ingredient in • Carboxylic acids with 12 to 20 carbon atoms are vinegar. often referred to as fatty acids, since they are found in the triglycerides in fats and oils (more later). – Butanoic acid is partially responsible for the odor of locker rooms and unwashed socks. • Short-chain carboxylic acids are also generally more soluble in water than compounds of similar MW, – Hexanoic acid is responsible for the odor of since they can hydrogen bond to more than one Limburger cheese. water molecule. • Like most acids, carboxylic acids tend to have a sour 15 taste (e.g., vinegar, citric acid, etc.) 16 Table 5.2 Physical properties of some carboxylic acids Boiling Points of Various Functional Groups Common Structural BP MP Solubility Name Formula (°C) (°C) (g/100 mL H2O) Formic acid H—CO2H 101 8 Infinite Acetic acid CH3—CO2H 118 17 Infinite Propionic acid CH3CH2—CO2H 141 -21 Infinite Butyric acid CH3(CH2)2—CO2H 164 -5 Infinite Valeric acid CH3(CH2)3—CO2H 186 -34 5 Caproic acid CH3(CH2)4—CO2H 205 -3 1 Caprylic acid CH3(CH2)6—CO2H 239 17 Insoluble Capric acid CH (CH ) —CO H 270 32 Insoluble Figure 5.4 3 2 8 2 The boiling points of Lauric acid CH3(CH2)10—CO2H 299 44 Insoluble carboxylic acids compared Myristic acid CH3(CH2)12—CO2H Dec. 58 Insoluble to 1° alcohols, aldehydes Palmitic acid CH (CH ) —CO H Dec. 63 Insoluble and ketones, ethers and 3 2 14 2 alkanes. Stearic acid CH3(CH2)16—CO2H Dec. 71 Insoluble 17 18 Chapter 5 Carboxylic Acids and Esters Comparing Physical Properties Examples: Predicting Physical Properties Boiling Point: Water Solubility: • Arrange the following compounds in order of Carboxylic acid increasing boiling point. (All of the compounds Carboxylic acid have about the same molecular weight.) Alcohols Alcohols Aldehydes/Ketones Aldehydes/Ketones – 1-pentanol Ethers Ethers – hexane Alkanes Alkanes – butanoic acid – pentanal Name Molecular Boiling Solubility in water weight point • Which member of each of the following pairs of Pentane 72 g/mol 35°C Insoluble compounds would you expect to have a higher Diethyl ether 74 g/mol 35°C Insoluble solubility in water? Butanal 72 g/mol 76°C 7.1 g / 100 mL H2O – 2-butanone or propanoic acid 1-Butanol 74 g/mol 118°C 9.1 g / 100 mL H2O – hexanoic acid or ethanoic acid Propanoic acid 74 g/mol 141°C Infinite 19 20 Important Carboxylic Acids O O O CH3CH2 C OH HOHC CH3 C OH Propanoic acid Methanoic acid Ethanoic acid (Propionic acid) (Formic acid) (Acetic acid) Found in Swiss cheese; (from Latin formica, ant) (from Latin acetum, vinegar) salts of this acid are used A component of the venom Vinegar is a 5% solution of as mold inhibitors of ants and caterpillars; acetic acid dissolved in water; produced in the body when acetic acid is also responsible methanol is consumed for the taste of sour wine (from Some Important the oxidation of ethanol) and sourdough bread Carboxylic Acids O O CH3CH2CH2 C OH CH3CH2CH2CH2CH2 C OH Butanoic acid Hexanoic acid (Butyric acid) (Caproic acid) (from Latin butyrum, butter) Responsible for the odor of This acid has a foul, rancid odor; Limburger cheese. produced from the breakdown of soft triglycerides in butter 21 22 O O OH O O OH HO HO OH OH O O OH H N Glycolic acid 2 An alpha-hydroxy acid used in OH 2-hydroxy-1,2,3-propanetricarboxylic acid cosmetics and skin creams; para-Aminobenzoic aid (PABA) OH (Citric acid) Used in sunscreens; absorbs alpha-hydroxy acids are thought to Found in citrus fruits (lemons, grapefruit, short-wavelength UV light. It is also required loosen the cells of the epidermis and 2-hydroxypropanoic acid oranges, etc.); commonly used in buffering by bacteria for the production of folic acid, accelerate the flaking off of dead skin; (Lactic acid) solutions with sodium citrate needed to maintain the growth of healthy cell however these compounds can increase Produced from the fermentation of sugars walls; sulfa drugs block the uptake of PABA the skin's sensitivity to UV light under anaerobic conditions; found in sweat, by bacteria, causing them to be unable to sour milk, fermented pickles, sauerkraut, manufacture folic acid, and thus preventing and yogurt; produced in muscles from O O glucose under anaerobic conditions (the the bacteria from multiplying O buildup of lactic acid leads to a heavy, weak feeling, and muscle cramps); produced after O O HO HO OH OH death during the breakdown of sugars in the Oxalic acid body by bacteria, inactivating the enzymes Found in many leafy green plants O OH that allow the transport of calcium ions, HO OH such as rhubarb and spinach; Malic acid causing rigor mortis combines with calcium ions in the Terephthalic acid Responsible for the sharp body to produce insoluble salts, A white, crystalline solid; used in taste of apples (genus Malus) which form kidney stones the manufacture of some polyesters 23 24 Chapter 5 Carboxylic Acids and Esters O OH O O HO H2N OH OH OH O OH Gamma-aminobutanoic acid (GABA) N A inhibitory neurotransmitter; ethanol binds to the same Niacin Tartaric acid protein as GABA at a neighboring location, distorting the A water-soluble, B-Complex vitamin obtained Found naturally in wine, and is protein so that GABA binds more easily, further inhibiting the from fish, green vegetables, lean meat, poultry, responsible for some of the sharp taste of cell from firing; benzodiazepines such as Valium also bind to whole-grain and enriched bread and cereal; wine; it is added to many sour-tasting the same protein but at a different site, inhibiting the cell still produced in the body from tryptophan; sweet foods.
Recommended publications
  • The Relative Rates of Thiol–Thioester Exchange and Hydrolysis for Alkyl and Aryl Thioalkanoates in Water

    The Relative Rates of Thiol–Thioester Exchange and Hydrolysis for Alkyl and Aryl Thioalkanoates in Water

    Orig Life Evol Biosph (2011) 41:399–412 DOI 10.1007/s11084-011-9243-4 PREBIOTIC CHEMISTRY The Relative Rates of Thiol–Thioester Exchange and Hydrolysis for Alkyl and Aryl Thioalkanoates in Water Paul J. Bracher & Phillip W. Snyder & Brooks R. Bohall & George M. Whitesides Received: 14 April 2011 /Accepted: 16 June 2011 / Published online: 5 July 2011 # Springer Science+Business Media B.V. 2011 Abstract This article reports rate constants for thiol–thioester exchange (kex), and for acid- mediated (ka), base-mediated (kb), and pH-independent (kw) hydrolysis of S-methyl thioacetate and S-phenyl 5-dimethylamino-5-oxo-thiopentanoate—model alkyl and aryl thioalkanoates, respectively—in water. Reactions such as thiol–thioester exchange or aminolysis could have generated molecular complexity on early Earth, but for thioesters to have played important roles in the origin of life, constructive reactions would have needed to compete effectively with hydrolysis under prebiotic conditions. Knowledge of the kinetics of competition between exchange and hydrolysis is also useful in the optimization of systems where exchange is used in applications such as self-assembly or reversible binding. For the alkyl thioester S-methyl thioacetate, which has been synthesized in −5 −1 −1 −1 −1 −1 simulated prebiotic hydrothermal vents, ka = 1.5×10 M s , kb = 1.6×10 M s , and −8 −1 kw = 3.6×10 s . At pH 7 and 23°C, the half-life for hydrolysis is 155 days. The second- order rate constant for thiol–thioester exchange between S-methyl thioacetate and 2- −1 −1 sulfonatoethanethiolate is kex = 1.7 M s .
  • Chapter 7, Haloalkanes, Properties and Substitution Reactions of Haloalkanes Table of Contents 1

    Chapter 7, Haloalkanes, Properties and Substitution Reactions of Haloalkanes Table of Contents 1

    Chapter 7, Haloalkanes, Properties and Substitution Reactions of Haloalkanes Table of Contents 1. Alkyl Halides (Haloalkane) 2. Nucleophilic Substitution Reactions (SNX, X=1 or 2) 3. Nucleophiles (Acid-Base Chemistry, pka) 4. Leaving Groups (Acid-Base Chemistry, pka) 5. Kinetics of a Nucleophilic Substitution Reaction: An SN2 Reaction 6. A Mechanism for the SN2 Reaction 7. The Stereochemistry of SN2 Reactions 8. A Mechanism for the SN1 Reaction 9. Carbocations, SN1, E1 10. Stereochemistry of SN1 Reactions 11. Factors Affecting the Rates of SN1 and SN2 Reactions 12. --Eliminations, E1 and E2 13. E2 and E1 mechanisms and product predictions In this chapter we will consider: What groups can be replaced (i.e., substituted) or eliminated The various mechanisms by which such processes occur The conditions that can promote such reactions Alkyl Halides (Haloalkane) An alkyl halide has a halogen atom bonded to an sp3-hybridized (tetrahedral) carbon atom The carbon–chlorine and carbon– bromine bonds are polarized because the halogen is more electronegative than carbon The carbon-iodine bond do not have a per- manent dipole, the bond is easily polarizable Iodine is a good leaving group due to its polarizability, i.e. its ability to stabilize a charge due to its large atomic size Generally, a carbon-halogen bond is polar with a partial positive () charge on the carbon and partial negative () charge on the halogen C X X = Cl, Br, I Different Types of Organic Halides Alkyl halides (haloalkanes) sp3-hybridized Attached to Attached to Attached
  • APPENDIX G Acid Dissociation Constants

    APPENDIX G Acid Dissociation Constants

    harxxxxx_App-G.qxd 3/8/10 1:34 PM Page AP11 APPENDIX G Acid Dissociation Constants §␮ ϭ 0.1 M 0 ؍ (Ionic strength (␮ † ‡ † Name Structure* pKa Ka pKa ϫ Ϫ5 Acetic acid CH3CO2H 4.756 1.75 10 4.56 (ethanoic acid) N ϩ H3 ϫ Ϫ3 Alanine CHCH3 2.344 (CO2H) 4.53 10 2.33 ϫ Ϫ10 9.868 (NH3) 1.36 10 9.71 CO2H ϩ Ϫ5 Aminobenzene NH3 4.601 2.51 ϫ 10 4.64 (aniline) ϪO SNϩ Ϫ4 4-Aminobenzenesulfonic acid 3 H3 3.232 5.86 ϫ 10 3.01 (sulfanilic acid) ϩ NH3 ϫ Ϫ3 2-Aminobenzoic acid 2.08 (CO2H) 8.3 10 2.01 ϫ Ϫ5 (anthranilic acid) 4.96 (NH3) 1.10 10 4.78 CO2H ϩ 2-Aminoethanethiol HSCH2CH2NH3 —— 8.21 (SH) (2-mercaptoethylamine) —— 10.73 (NH3) ϩ ϫ Ϫ10 2-Aminoethanol HOCH2CH2NH3 9.498 3.18 10 9.52 (ethanolamine) O H ϫ Ϫ5 4.70 (NH3) (20°) 2.0 10 4.74 2-Aminophenol Ϫ 9.97 (OH) (20°) 1.05 ϫ 10 10 9.87 ϩ NH3 ϩ ϫ Ϫ10 Ammonia NH4 9.245 5.69 10 9.26 N ϩ H3 N ϩ H2 ϫ Ϫ2 1.823 (CO2H) 1.50 10 2.03 CHCH CH CH NHC ϫ Ϫ9 Arginine 2 2 2 8.991 (NH3) 1.02 10 9.00 NH —— (NH2) —— (12.1) CO2H 2 O Ϫ 2.24 5.8 ϫ 10 3 2.15 Ϫ Arsenic acid HO As OH 6.96 1.10 ϫ 10 7 6.65 Ϫ (hydrogen arsenate) (11.50) 3.2 ϫ 10 12 (11.18) OH ϫ Ϫ10 Arsenious acid As(OH)3 9.29 5.1 10 9.14 (hydrogen arsenite) N ϩ O H3 Asparagine CHCH2CNH2 —— —— 2.16 (CO2H) —— —— 8.73 (NH3) CO2H *Each acid is written in its protonated form.
  • Basic Principles and Analytical Application of Derivative Spectrophotometry

    Basic Principles and Analytical Application of Derivative Spectrophotometry

    13 Basic Principles and Analytical Application of Derivative Spectrophotometry Joanna Karpinska Institute of Chemistry, University of Bialystok, Bialystok Poland 1. Introduction Analytical methods based on measurements of UV or visible light absorption belong to the most popular and most often used in laboratory practice. Commercially available apparatuses are cheap and easy for operation. Spectrophotometric procedures usually are not time- and labour-consuming. The economical aspects of UV-Vis techniques is worth of emphasize too. It is one of the cheapest technique, so spectrophotometers are basic equipment of every laboratory. The main disadvantage and limitation of the spectrophotometry is its low selectivity. The measurement of absorbance is burden by interferences derived from others components of sample. A recorded UV-Vis spectrum is the sum of absorbances of analyte and matrix. Usually, recorded bands are well-defined but more or less distorted by a background. As the background is called absorbance exhibited by matrix (reagents or accompanied compounds). The problem with specific or nonspecific background can be omitted by measurements versus blank. Such procedure can be successfully applied only in the case of simple samples, which composition is stable and well known or when highly selective reagents are used. An isolation of an analyte from matrix is another solution for increasing the selectivity of assay. But every additional operation introduced into sample preparation procedure extents time and costs of single analysis and increases risk of loss or contamination of the analyte. One of the simplest method for an increasing a selectivity is derivatisation of spectra. This operation allows to remove spectral interferences and as a consequence leads to increase selectivity of assay.
  • Introduction to Alkenes and Alkynes in an Alkane, All Covalent Bonds

    Introduction to Alkenes and Alkynes in an Alkane, All Covalent Bonds

    Introduction to Alkenes and Alkynes In an alkane, all covalent bonds between carbon were σ (σ bonds are defined as bonds where the electron density is symmetric about the internuclear axis) In an alkene, however, only three σ bonds are formed from the alkene carbon -the carbon thus adopts an sp2 hybridization Ethene (common name ethylene) has a molecular formula of CH2CH2 Each carbon is sp2 hybridized with a σ bond to two hydrogens and the other carbon Hybridized orbital allows stronger bonds due to more overlap H H C C H H Structure of Ethylene In addition to the σ framework of ethylene, each carbon has an atomic p orbital not used in hybridization The two p orbitals (each with one electron) overlap to form a π bond (p bonds are not symmetric about the internuclear axis) π bonds are not as strong as σ bonds (in ethylene, the σ bond is ~90 Kcal/mol and the π bond is ~66 Kcal/mol) Thus while σ bonds are stable and very few reactions occur with C-C bonds, π bonds are much more reactive and many reactions occur with C=C π bonds Nomenclature of Alkenes August Wilhelm Hofmann’s attempt for systematic hydrocarbon nomenclature (1866) Attempted to use a systematic name by naming all possible structures with 4 carbons Quartane a alkane C4H10 Quartyl C4H9 Quartene e alkene C4H8 Quartenyl C4H7 Quartine i alkine → alkyne C4H6 Quartinyl C4H5 Quartone o C4H4 Quartonyl C4H3 Quartune u C4H2 Quartunyl C4H1 Wanted to use Quart from the Latin for 4 – this method was not embraced and BUT has remained Used English order of vowels, however, to name the groups
  • Optimisation Du Métabolisme Énergétique Du Soufre Chez La Bactérie Hyperthermophile Aquifex Aeolicus

    Optimisation Du Métabolisme Énergétique Du Soufre Chez La Bactérie Hyperthermophile Aquifex Aeolicus

    Aix-Marseille Université Ecole Doctorale des Sciences de la Vie et de la Santé Thèse de Doctorat d’Université Mention Microbiologie Clément AUSSIGNARGUES Optimisation du métabolisme énergétique du soufre chez la bactérie hyperthermophile Aquifex aeolicus Soutenue le 17 Décembre 2012 devant le jury: Pr. Frédéric BARRAS Dr. Laurent COURNAC Dr. Bruno FRANZETTI Dr. Marie-Thérèse GIUDICI-ORTICONI Dr. Anne GODFROY Dr. Marianne ILBERT Laboratoire de Bioénergétique et Ingénierie des Protéines Centre National de la Recherche Scientifique Aix-Marseille Université Ecole Doctorale des Sciences de la Vie et de la Santé Thèse de Doctorat d’Université Mention Microbiologie Clément AUSSIGNARGUES Optimisation du métabolisme énergétique du soufre chez la bactérie hyperthermophile Aquifex aeolicus Soutenue le 17 Décembre 2012 devant le jury: Pr. Frédéric BARRAS Dr. Laurent COURNAC Dr. Bruno FRANZETTI Dr. Marie-Thérèse GIUDICI-ORTICONI Dr. Anne GODFROY Dr. Marianne ILBERT Laboratoire de Bioénergétique et Ingénierie des Protéines Centre National de la Recherche Scientifique Sommaire Sommaire Introduction 2 Chapitre I- Métabolismes énergétiques du soufre 4 I) Le soufre, un élément essentiel aux multiples facettes 6 II) Le soufre utilisé comme composé énergétique 9 A) Oxydation des composés du soufre 10 1. Oxydation du sulfure d’hydrogène H2S 10 a) La Sulfure Quinone Oxydoréductase (SQR) 10 b) La flavocytochrome c sulfure déshydrogénase (FCSD) 13 2- 2. Oxydation du thiosulfate (S2O3 ) 14 a) Thiosulfate : accepteur oxydoréductase (TAOR) 14 b) Le système Sox 16 2- 3. Oxydation du sulfite (SO3 ) 20 a) Sulfite : accepteur oxydoréductase (SAOR) 21 b) Voie de l’APS 23 4. Oxydation du soufre stocké dans les globules 26 B) La réduction du soufre : soufre/polysulfure réductase 29 C) Un cas particulier : la dismutation du soufre (SOR) 33 1.
  • Linear Alkylbenzene Sulphonate (CAS No

    Linear Alkylbenzene Sulphonate (CAS No

    Environmental Risk Assessment LAS Linear Alkylbenzene Sulphonate (CAS No. 68411-30-3) Revised ENVIRONMENTAL Aspect of the HERA Report = February 2013 = 1 1. Contents 2. Executive summary 3. Substance characterisation 3.1 CAS No. and grouping information 3.2 Chemical structure and composition 3.3 Manufacturing route and production/volume statistics 3.4 Consumption scenario in Europe 3.5 Use application summary 4. Environmental safety assessment 4.1 Environmental exposure assessment 4.1.1 Biotic and abiotic degradability 4.1.2 Removal 4.1.3 Monitoring studies 4.1.4 Exposure assessment: scenario description 4.1.5 Substance data used for the exposure calculation 4.1.6 PEC calculations 4.1.7 Bioconcentration 4.2 Environmental effects assessment 4.2.1 Ecotoxicity 4.2.1.1 Aquatic ecotoxicity 4.2.1.2 Terrestrial ecotoxicity 4.2.1.3 Sediment ecotoxicity 4.2.1.4 Ecotoxicity to sewage microorganisms 4.2.1.5 Reassurance on absence of estrogenic effects 4.2.2 PNEC calculations 4.2.2.1 Aquatic PNEC 4.2.2.2 Terrestrial PNEC 4.2.2.3 Sludge PNEC 4.2.2.4 Sediment PNEC 4.2.2.5 STP PNEC 4.3 Environment risk assessment 5. 5. References 6. Contributors to the report 6.1 Substance team 6.2 HERA environmental task force 6.3 HERA human health task force 6.4 Industry coalition for the OECD/ICCA SIDS assessment of LAS 2 2. Executive Summary Linear alkylbenzene sulphonate (LAS) is an anionic surfactant. It was introduced in 1964 as the readily biodegradable replacement for highly branched alkylbenzene sulphonates (ABS).
  • Functional Group Transformations in Derivatives Of

    Functional Group Transformations in Derivatives Of

    Article pubs.acs.org/joc Functional Group Transformations in Derivatives of 1,4- Dihydrobenzo[1,2,4]triazinyl Radical † § † ∥ † ‡ † ⊥ Agnieszka Bodzioch, , Minyan Zheng, , Piotr Kaszynski,́ *, , and Greta Utecht , † Organic Materials Research Group Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37235, United States ‡ Faculty of Chemistry, University of Łodź,́ Tamka 12, 91403 Łodź,́ Poland *S Supporting Information ABSTRACT: Transformations of functional groups OCOPh, ’ − OCH2Ph, I, NO2, and CO2Me in Blatter s radical derivatives 1 5 were investigated in order to develop synthetic tools for incorporation of the benzo[1,2,4]triazinyl system into complex molecular architectures. Thus, basic hydrolysis of OCOPh or Pd-catalyzed debenzylation of OCH2Ph gave phenol functionality, which was acylated and alkylated. Pd-catalyzed Suzuki, Negishi, Sonogashira, and Heck C−C cross-coupling reactions of iodo derivatives 1c, 1d, and 2d ffi were also successful and e cient. Reduction of NO2 in 1e led to aniline derivative 1t, which was reductively alkylated with hexanal and coupled to L-proline. Selected benzo[1,2,4]triazinyl radicals were characterized by EPR and electronic absorption spectroscopy, and the results were analyzed in tandem with DFT computational methods. Lastly, the mechanism for formation of the 1,4- dihydrobenzo[1,2,4]triazine ring was investigated using the B3LYP/6-31G(2d,p) method. ■ INTRODUCTION little attention, and only a handful of derivatives have been Stable π-delocalized radicals are becoming important structural reported in the literature. This situation changed several years elements of materials for solar cells,1 energy storage,2 ago when Koutentis began systematic development of synthetic − electronic,3,4 and biological5 8 applications.9,10 Their incorpo- access to this class of radicals.
  • Ester Synthesis Lab (Student Handout)

    Ester Synthesis Lab (Student Handout)

    Name: ________________________ Lab Partner: ____________________ Date: __________________________ Class Period: ____________________ Ester Synthesis Lab (Student Handout) Lab Report Components: The following must be included in your lab book in order to receive full credit. 1. Purpose 2. Hypothesis 3. Procedure 4. Observation/Data Table 5. Results 6. Mechanism (In class) 7. Conclusion Introduction The compounds you will be making are also naturally occurring compounds; the chemical structure of these compounds is already known from other investigations. Esters are organic molecules of the general form: where R1 and R2 are any carbon chain. Esters are unique in that they often have strong, pleasant odors. As such, they are often used in fragrances, and many artificial flavorings are in fact esters. Esters are produced by the reaction between alcohols and carboxylic acids. For example, reacting ethanol with acetic acid to give ethyl acetate is shown below. + → + In the case of ethyl acetate, R1 is a CH3 group and R2 is a CH3CH2 group. Naming esters systematically requires naming the functional groups on both sides of the bridging oxygen. In the example above, the right side of the ester as shown is a CH3CH2 1 group, or ethyl group. The left side is CH3C=O, or acetate. The name of the ester is therefore ethyl acetate. Deriving the names of the side from the carboxylic acid merely requires replacing the suffix –ic with –ate. Materials • Alcohol • Carboxylic Acid o 1 o A o 2 o B o 3 o C o 4 Observation Parameters: • Record the combination of carboxylic acid and alcohol • Observe each reactant • Observe each product Procedure 1.
  • In This Handout, All of Our Functional Groups Are Presented As Condensed Line Formulas, 2D and 3D Formulas and with Nomenclature Prefixes and Suffixes (If Present)

    In This Handout, All of Our Functional Groups Are Presented As Condensed Line Formulas, 2D and 3D Formulas and with Nomenclature Prefixes and Suffixes (If Present)

    In this handout, all of our functional groups are presented as condensed line formulas, 2D and 3D formulas and with nomenclature prefixes and suffixes (if present). Organic names are built on a foundation of alkanes, alkenes and alkynes. Those examples are presented first and you need to know those rules. The strategies can be found in Chapter 4 of our textbook (alkanes: pages 93-98, cycloalkanes 102-104, alkenes: pages 104-110, alkynes: pages 112-113 and combinations of all of them 113-115). After introducing examples of alkanes, alkenes, alkynes and combinations of them, the functional groups are presented in order of priority. A few nomenclature examples are provided for each of the functional groups. Examples of the various functional groups are presented on pages 115-135 in the textbook. Two overview pages are on pages 136-137. Some functional groups have a suffix name when they are the highest priority functional group and a prefix name when they are not the highest priority group, and these are added to the skeletal names with identifying numbers and stereochemistry terms (E and Z for alkenes, R and S for chiral centers and cis and trans for rings). Several low priority functional groups only have a prefix name. A few additional special patterns are shown on pages 98-102. The only way to learn this topic is practice (over and over). The best practice approach is to actually write out the names (on an extra piece of paper or on a white board, and then do it again). The same functional groups are used throughout the entire course.
  • And Intermolecular Addition of Carboxylic Acids to Alkynes in Aqueous Media: a Review

    And Intermolecular Addition of Carboxylic Acids to Alkynes in Aqueous Media: a Review

    catalysts Review Metal-Catalyzed Intra- and Intermolecular Addition of Carboxylic Acids to Alkynes in Aqueous Media: A Review Javier Francos and Victorio Cadierno * Laboratorio de Compuestos Organometálicos y Catálisis (Unidad Asociada al CSIC), Centro de Innovación en Química Avanzada (ORFEO-CINQA), Departamento de Química Orgánica e Inorgánica, IUQOEM, Facultad de Química, Universidad de Oviedo, Julián Clavería 8, E-33006 Oviedo, Spain; [email protected] * Correspondence: [email protected]; Tel.: +34-985-103453 Received: 19 October 2017; Accepted: 2 November 2017; Published: 6 November 2017 Abstract: The metal-catalyzed addition of carboxylic acids to alkynes is a very effective tool for the synthesis of carboxylate-functionalized olefinic compounds in an atom-economical manner. Thus, a large variety of synthetically useful lactones and enol-esters can be accessed through the intra- or intermolecular versions of this process. In order to reduce the environmental impact of these reactions, considerable efforts have been devoted in recent years to the development of catalytic systems able to operate in aqueous media, which represent a real challenge taking into account the tendency of alkynes to undergo hydration in the presence of transition metals. Despite this, different Pd, Pt, Au, Cu and Ru catalysts capable of promoting the intra- and intermolecular addition of carboxylic acids to alkynes in a selective manner in aqueous environments have appeared in the literature. In this review article, an overview of this chemistry is provided. The synthesis of b-oxo esters by catalytic addition of carboxylic acids to terminal propargylic alcohols in water is also discussed. Keywords: aqueous catalysis; alkynes; carboxylic acids; alkynoic acids; hydrocarboxylation reactions; cycloisomerization reactions; enol esters; lactones; b-oxo esters 1.
  • Chemical Equilibria of Aqueous Ammonium–Carboxylate

    Chemical Equilibria of Aqueous Ammonium–Carboxylate

    PCCP View Article Online PAPER View Journal | View Issue Chemical equilibria of aqueous ammonium– carboxylate systems in aqueous bulk, close Cite this: Phys. Chem. Chem. Phys., 2019, 21,12434 to and at the water–air interface† a a a Yina Salamanca Blanco,‡ O¨ nder Topel, § E´va G. Bajno´czi, ab b a Josephina Werner, Olle Bjo¨rneholm and Ingmar Persson * Previous studies have shown that the water–air interface and a number of water molecule layers just below it, the surface region, have significantly different physico-chemical properties, such as lower relative permittivity and density, than bulk water. The properties in the surface region of water favor weakly hydrated species as neutral molecules, while ions requiring strong hydration and shielding of their charge are disfavored. In this + À study the equilibria NH4 (aq) + RCOO (aq) " NH3(aq) + RCOOH(aq) are investigated for R = CnH2n+1, n = 0–8, as open systems, where ammonia and small carboxylic acids in the gas phase above the water surface are removed from the system by a gentle controlled flow of nitrogen to mimic the transport of volatile com- Creative Commons Attribution 3.0 Unported Licence. pounds from water droplets into air. It is shown that this non-equilibrium transport of chemicals can be sufficiently large to cause a change of the chemical content of the aqueous bulk. Furthermore, X-ray photoelectron spectroscopy (XPS) has been used to determine the relative concentration of alkyl carboxylic acids and their conjugated alkyl carboxylates in aqueous surfaces using a micro-jet. These studies confirm that neutral alkyl carboxylic acids are accumulated in the surface region, while charged species, as alkyl carboxylates, are depleted.