The Arene–Alkene Photocycloaddition
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
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 . -
Solvent Effects on Structure and Reaction Mechanism: a Theoretical Study of [2 + 2] Polar Cycloaddition Between Ketene and Imine
J. Phys. Chem. B 1998, 102, 7877-7881 7877 Solvent Effects on Structure and Reaction Mechanism: A Theoretical Study of [2 + 2] Polar Cycloaddition between Ketene and Imine Thanh N. Truong Henry Eyring Center for Theoretical Chemistry, Department of Chemistry, UniVersity of Utah, Salt Lake City, Utah 84112 ReceiVed: March 25, 1998; In Final Form: July 17, 1998 The effects of aqueous solvent on structures and mechanism of the [2 + 2] cycloaddition between ketene and imine were investigated by using correlated MP2 and MP4 levels of ab initio molecular orbital theory in conjunction with the dielectric continuum Generalized Conductor-like Screening Model (GCOSMO) for solvation. We found that reactions in the gas phase and in aqueous solution have very different topology on the free energy surfaces but have similar characteristic motion along the reaction coordinate. First, it involves formation of a planar trans-conformation zwitterionic complex, then a rotation of the two moieties to form the cycloaddition product. Aqueous solvent significantly stabilizes the zwitterionic complex, consequently changing the topology of the free energy surface from a gas-phase single barrier (one-step) process to a double barrier (two-step) one with a stable intermediate. Electrostatic solvent-solute interaction was found to be the dominant factor in lowering the activation energy by 4.5 kcal/mol. The present calculated results are consistent with previous experimental data. Introduction Lim and Jorgensen have also carried out free energy perturbation (FEP) theory simulations with accurate force field that includes + [2 2] cycloaddition reactions are useful synthetic routes to solute polarization effects and found even much larger solvent - formation of four-membered rings. -
Selective Hydrogenation of Cyclopentadiene to Form Cyclopentene
European Patent Office (n) Publication number: 0 009 035 Office europeen des brevets A1 EUROPEAN PATENT APPLICATION {ry Application number: 79930020.7 © lnt.CI.3: C 07 C 13/12 C 07 C 5/05, B 01 J 31/14 (22) Date of filing: 27.08.79 B 01 J 31/12 (30) Priority: 30.08.78 US 938159 (71) Applicant: THE GOODYEAR TIRE 8t RUBBER COMPANY 1144 East Market Street Akron, Ohio, 44316IUS) i*3) uaie ot puDiication ot application: 19.03.80 Bulletin 80 6 [73) Inventor: Menapace, Henry Robert 1738 Washington Circle @ Designated Contracting States: Stow Ohio 44224(US) BE DE FR GB IT NL g) Representative: Zewen, Arthur 4 Place Winston Churchill B.P. 447 Luxembourg-VillelLU ) {&) Selective hydrogenation of cyclopentadiene to form cyclopentene. where (57) Theremere is oiscloseddisclosed a process torfor the preparation otof cyc- wnere Hi,R1, H2R2 and R3 may bebe hydrogen or halogen, or an alkyl lopentene which comprises selectively hydrogenating cyc- radical containing from 1 to 6 carbon atoms; R,OR,R1OR2 wherein lopentadiene in a liquid phase by contacting cyclopentadiene R,Ri and R2 may bebe the same or different alkyl radicals contain- from with hydrogen in the presence of a hydrogenation catalyst inging 1 to 6 carbon atoms; and R^CR^ comprising (1(1) ) a soluble nickel compound, (2) an 0wherein wherein R,R1 may be organoaluminum compound or a lithium alkyl compound, alkylilkyl or an aromatic radical containing from 1 to 8 and (3) at least selected from the carbon one cocatalyst compound atomsitoms and RsR2 may be hydrogen or an alkyl or aromatic hyd- group consisting of HjO;H2O; NH3; ROH where R is an alkyl or a rocarbonocarbon radical containing from 1 to 8 carbon atoms. -
Spirocyclic-2-Oxindoles from Morita-Baylis- Hillman Adduct of Isatin
Synthesis of Functionalized 2-Oxindoles and 3- Spirocyclic-2-Oxindoles from Morita-Baylis- Hillman Adduct of Isatin THESIS SUBMITTED TO THE UNIVERSITY OF KERALA IN FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY IN CHEMISTRY UNDER THE FACULTY OF SCIENCE BY K. SELVAKUMAR ORGANIC CHEMISTRY SECTION NATIONAL INSTITUTE FOR INTERDISCIPLINARY SCIENCE AND TECHNOLOGY (CSIR) THIRUVANANTHAPURAM-695 019 KERALA, INDIA 2012 …To my beloved family DECLARATION I hereby declare that Ph. D. thesis entitled “Synthesis of Functionalized 2-Oxindoles and 3-Spirocyclic-2-Oxindoles from Morita-Baylis-Hillman Adduct of Isatin” is an independent work carried out by me and it has not been submitted anywhere else for any other degree, diploma or title. K. Selvakumar Thiruvananthapuram 2012 i CERTIFICATE This is to certify that the work embodied in the thesis entitled “Synthesis of Functionalized 2-Oxindoles and 3-Spirocyclic-2-Oxindoles from Morita- Baylis-Hillman Adduct of Isatin” has been carried out by Mr. K. Selvakumar under our combined supervision at the Chemical Sciences and Technology Division of National Institute for Interdisciplinary Science and Technology (CSIR), Thiruvananthapuram and the same has not been submitted elsewhere for any other degree. Dr. R. LUXMI VARMA Dr. P. SHANMUGAM (Thesis supervisor) (Thesis supervisor) Thiruvananthapuram ii ACKNOWLEDGEMENTS At the outset, I express my sincere and heartfelt gratitude to my research supervisor Dr. P. Shanmugam for suggesting me interesting research topic and for his care, constructive criticism and continuous support throughout my doctoral studies. I would like to offer special thanks to Dr. R. Luxmi Varma, Co-guide for her suggestions, encouragement and timely help during the tenure of this work. -
Cyclopentyl Methyl Ether (CPME)
Korean J. Chem. Eng., 34(2), 463-469 (2017) pISSN: 0256-1115 DOI: 10.1007/s11814-016-0265-5 eISSN: 1975-7220 INVITED REVIEW PAPER Measurement and correlation of the isothermal VLE data for the binary mixtures of cyclopentene (CPEN)+cyclopentyl methyl ether (CPME) Wan Ju Jeong and Jong Sung Lim† Department of Chemical and Biomolecular Engineering, Sogang University, C.P.O. Box 1142, Seoul 04107, Korea (Received 2 August 2016 • accepted 20 September 2016) Abstract−The isothermal vapor-liquid equilibrium data for the binary systems of cyclopentene (1)+cyclopentyl methyl ether (2) were measured at 313.15, 323.15, 333.15, 343.15 and 353.15 K using a dynamic-type equilibrium apparatus and online gas chromatography analysis. For all the measured VLE data consistency tests were performed for the verifi- cation of data using Barker’s method and the ASPEN PLUS Area Test method. All the resulting average absolute val- δ γ γ ues of residuals [ ln ( 1/ 2)] for Barker’s method and D values for the ASPEN PLUS area test method were com- paratively small. So, the VLE data reported in this study are considered to be acceptable. This binary system shows neg- ative deviation from Raoult’s law and does not exhibit azeotropic behavior at whole temperature ranges studied here. The measured data were correlated with the P-R EoS using the Wong-Sandler mixing rule. The overall average relative deviation of pressure (ARD-P (%)) between experimental and calculated values was 0.078% and that of vapor phase compositions (ARD-y (%)) was 0.452%. Keywords: Vapor Liquid Equilibria (VLE), Cyclopentyl Methyl Ether (CPME), Cyclopentene (CPEN), Peng-Robinson Equation of State (PR-EoS), Wong-Sandler Mixing Rule (WS-MR) INTRODUCTION however, have some disadvantages because they use dimethyl sul- fate and methyl iodide as a reactant, respectively, which are muta- Ethers are widely used in organic chemistry and biochemistry. -
Stereochemistry CHAPTER3
28 Stereochemistry CHAPTER3 Stereochemistry Stereochemistry : It involves the study of the relative spatial arrangement of atoms within the molecules. Dynamic stereochemistry: Dynamic stereochemistry is the study of the effect of stereochemistry on the rate of a chemical reaction. First Stereochemist – Louis Pasteur (1849): Significance of stereochemistry: One of the most infamous demonstration of the significance of stere- ochemistry was the Thalidomide disaster. Thalidomide is a drug was first prepared in 1957 in Germany, prescribed for treating morning Sickness in pregnant women. It was discovered that one optical isomer i.e. R- Isomer of the drug was safe whereas the S-isomer had teratogenic effect, causing serious genetic damage to early embryonic growth and development. O O H O O H N N 1 2 N 3 O N O H H 4 O R-isomer O S-isomer Drug for morning sickness in pregnant women. Teratogenic effect [Remark: In human body, Thalidomide undergoes racemization: even if only one of the two stereoisomers is ingested, the other one is produced.] Now we have another example - Propanolol. H H N N O O H OH OH H R-Propanolol (contraceptive) S-Propanolol (antihypertensive) Stereochemistry 29 SOME TERMINOLOGY Optical activity: The term optical activity derived from the interaction of chiral materials with polarized light. Scalemic: Any non-racemic chiral substance is called Scalemic. • A chiral substance is enantio pure or homochiral when only one of two possible enantiomer is present. • A chiral substance is enantio enriched or heterochiral when an excess of one enantiomer is present but not the exclusion of the other. -
Secondary Organic Aerosol Formation from the Ozonolysis of Cycloalkenes and Related Compounds*
252 Chapter 7 Secondary Organic Aerosol Formation from the Ozonolysis of Cycloalkenes and Related Compounds* * This chapter is reproduced by permission from “Secondary organic aerosol formation from ozonolysis of cycloalkenes and related compounds” by M.D. Keywood, V. Varutbangkul, R. Bahreini, R.C. Flagan, J.H. Seinfeld, Environmental Science and Technology, 38 (15): 4157-4164, 2004. Copyright 2004, American Chemical Society. 253 7.1. Abstract The secondary organic aerosol (SOA) yields from the laboratory chamber ozonolysis of a series of cycloalkenes and related compounds are reported. The aim of this work is to investigate the effect of the structure of the hydrocarbon parent molecule on SOA formation for a homologous set of compounds. Aspects of the compound structures that are varied include the number of carbon atoms present in the cycloalkene ring (C5 to C8), the presence and location of methyl groups, and the presence of an exocyclic or endocyclic double bond. The specific compounds considered here are cyclopentene, cyclohexene, cycloheptene, cyclooctene, 1-methyl-1-cyclopentene, 1-methyl-1- cyclohexene, 1-methyl-1-cycloheptene, 3-methyl-1-cyclohexene, and methylene cyclohexane. SOA yield is found to be a function of the number of carbons present in the cycloalkene ring, with increasing number resulting in increased yield. Yield is enhanced by the presence of a methyl group located at a double-bonded site but reduced by the presence of a methyl group at a non-double bonded site. The presence of an exocyclic double bond also leads to a reduced yield relative to the equivalent methylated cycloalkene. On the basis of these observations, the SOA yield for terpinolene relative to the other cyclic alkenes is qualitatively predicted, and this prediction compares well to measurements of SOA yield from the ozonolysis of terpinolene. -
(12) United States Patent (10) Patent No.: US 7.494,962 B2 Kinet Al
USOO74949.62B2 (12) United States Patent (10) Patent No.: US 7.494,962 B2 Kinet al. (45) Date of Patent: Feb. 24, 2009 (54) SOLVENTS CONTAINING CYCLOAKYL (56) References Cited ALKYLETHERS AND PROCESS FOR PRODUCTION OF THE ETHERS U.S. PATENT DOCUMENTS 3496,223 A * 2/1970 Mitchell et al. ............... 562/22 (75) Inventors: Idan Kin, Ottawa (CA); Genichi Ohta, Tokyo (JP); Kazuo Teraishi, Tokyo (JP); Kiyoshi Watanabe, Tokyo (JP) (Continued) (73) Assignee: Zeon Corporation, Tokyo (JP) FOREIGN PATENT DOCUMENTS (*) Notice: Subject to any disclaimer, the term of this EP 587434 A1 3, 1994 patent is extended or adjusted under 35 U.S.C. 154(b) by 349 days. (Continued) (21) Appl. No.: 10/481,340 OTHER PUBLICATIONS (22) PCT Filed: Jun. 27, 2002 Edited by Kagaku Daijiten Henshu Iinkai, “Kagaku Daijiten 9”. (86). PCT No.: PCT/UP02/06501 Kyoritsu Shuppan Co., Ltd., Aug. 25, 1962, p. 437, "Yozai'. (Continued) S371 (c)(1), (2), (4) Date: Sep. 24, 2004 Primary Examiner Gregory E Webb (74) Attorney, Agent, or Firm—Birch, Stewart, Kolasch & (87) PCT Pub. No.: WO03/002500 Birch, LLP PCT Pub. Date: Jan. 9, 2003 (57) ABSTRACT (65) Prior Publication Data The present inventions are (A) a solvent comprising at least US 2005/OO65060A1 Mar. 24, 2005 one cycloalkyl alkyl ether (1) represented by the general O O formula: R1-O R2 (wherein R1 is cyclopentyl or the like: (30) Foreign Application Priority Data and R2 is C1-10 alkyl or the like); (B) a method of prepara Jun. 28, 2001 (JP) ............................. 2001-196766 tions the ethers (1) characterized by reacting an alicyclic Oct. -
Organic Chemistry Frontiers
ORGANIC CHEMISTRY FRONTIERS View Article Online REVIEW View Journal | View Issue Progress in the synthesis of perylene bisimide dyes Cite this: Org. Chem. Front., 2019, 6, Agnieszka Nowak-Król and Frank Würthner * 1272 With their versatile absorption, fluorescence, n-type semiconducting and (photo-)stability properties, per- ylene bisimides have evolved as the most investigated compounds among polycyclic aromatic hydro- carbons during the last decade. In this review we collect the results from about 200 original publications, reporting a plethora of new perylene bisimide derivatives whose properties widely enrich the possibility for the application of these dyes beyond traditional fields. While some applications are highlighted, different from other recent reviews, our focus here is on the advances in the synthetic methodologies Received 17th December 2018, that have afforded new bay functionalizations, recently addressed functionalizations at the ortho-positions Accepted 17th February 2019 to the carbonyl groups, and annulation of carbo- and heterocyclic units. An impressive number of DOI: 10.1039/c8qo01368c perylene bisimide oligomers are highlighted as well which are connected by single bonds or spiro linkage rsc.li/frontiers-organic or in a fused manner, leading to arrays with fascinating optical and electronic properties. Creative Commons Attribution 3.0 Unported Licence. Introduction are the leading examples of the class of tetrapyrrole dyes, PBIs are the most important compounds of the family of polycyclic About a hundred years after their discovery, perylene-3,4:9,10- aromatic hydrocarbons. This outstanding role of PBIs has bis(dicarboximide)s, commonly abbreviated as PDIs or PBIs, evolved not only due to their properties, but also due to the have emerged as one of the most important classes of func- incredible development of the synthetic chemistry of this class tional dyes. -
Epoxidation of Cyclopentene, Cyclohexene and Cycloheptene by Acetylperoxyl Radicals
Epoxidation of Cyclopentene, Cyclohexene and Cycloheptene by Acetylperoxyl Radicals J. R. Lindsay Smith, D. M. S. Smith, M. S. Stark* and D. J. Waddington Department of Chemistry, University of York, York, YO10 5DD, United Kingdom To further the current understanding of how peroxyl radicals add to C=C double bonds,eg. 1-3 a series of cyclic alkenes (cyclopentene, cyclohexene and cycloheptene) were reacted with acetylperoxyl radicals over the temperature range 373 - 433 K, via the co- oxidation of acetaldehyde, the cyclic alkene and a reference alkene. The resulting epoxides were monitored by GC-FID, allowing the determination of the Arrhenius parameters given in Table 1 for these addition reactions. 3 -1 -1 -1 Alkene log10(A / dm mol s ) Eact / kJ mol cyclopentene 9.7±0.6 31.2±5.0 cyclohexene 7.7±0.7 17.4±5.3 cycloheptene 8.8±0.8 25.5±6.5 cis-2-butene4 8.1±0.5 22.9±3.8 Table 1: Arrhenius parameters for the addition of acetylperoxyl radicals to cyclic alkenes and cis-2-butene. Parameters for cis-2-butene are also given for comparison,4 as it would be expected that a relatively unstrained cycloalkene would behave in a similar manner to this non-cyclic alkene; this is indeed found to be so, with no statistically significant difference between cyclohexene and cis-2-butene. Indeed the measured activation energy for cyclohexene fits in well with correlation between charge transfer ( Ec) and activation energy that is known to exist for the addition of acetylperoxyl to acyclic mono-alkenes.1 Cyclopentene however does have a significantly larger pre-exponential factor and activation energy than either cyclohexene or cis-2-butene. -
Copyrighted Material
Index Abbreviations receptor sites 202, 211 weak 122 amino acids, Table 500–1 muscarinic 413 weak, pH calculation 147–8 nucleic acids 551 nicotinic 413 Acid–base nucleotides, Table 551 as quaternary ammonium salt 202 catalysis, enzymes 516 peptides and proteins 504 Acetylcholinesterase equilibria 121 phosphates and diphosphates 277 enzyme mechanism 519–21 interactions, predicting 155–7 structural, Table 14 hydrolysis of acetylcholine 279 Acidic reagents, Table 157 ACE (angiotensin-converting enzyme) inhibitors 279 Acidity enzyme action 532 Acetyl-CoA carboxylase, in fatty acid acidity constant 122 inhibitors 532 biosynthesis 595 bond energy effects 125 Acetal Acetyl-CoA (acetyl coenzyme A) definition 121 in etoposide 233 as acylating agent 262 electronegativity effects 125 formation 229 carboxylation to malonyl-CoA 595, hybridization effects 128 polysaccharides as polyacetals 232 609 inductive effects 125–7 as protecting group 230 Claisen reaction 381 influence of electronic and structural Acetal and ketal enolate anions 373 features 125–34 cyclic, as protecting groups 481 in Krebs cycle 585 and leaving groups, Table 189 groups in sucrose 231 from β-oxidation of fatty acids 388 pKa values 122–5 Acetaldehyde, basicity 139 as thioester 262, 373 resonance / delocalization effects 129–34 Acetamide, basicity 139 Acetylene, bonding molecular orbitals 31 Acidity (compounds) Acetaminophen, see paracetamol Acetylenes, acidity 128 acetone 130 Acetoacetyl-CoA, biosynthesis from N-Acetylgalactosamine, in blood group acetonitrile 365 acetyl-CoA 392 -
Organic Stereoisomerism
Organic : Stereoisomerism Stereoisomerism Introduction: When two compounds have same structure(hence same name) but still they are not identical and some of their properties are different then it means they are stereoisomers. They are not superimposable with each other. They differ in the spatial relationship between their atoms or groups. See this example. CH3 CH3 CH3 H CC CC H H H CH3 cis(Z)-but-2-ene trans(E)-but-2-ene Both are but-2-ene, but they are not identical. Their melting points and boiling points are different. They evolve different heat energy when hydrogenated. So what is the difference between them ? Is it structure- wise ? The answer is NO, as their structures are same i.e but-2-ene. They differ with respect the relationship between some atoms or groups in space. In cis-but-2-ene, the –CH3 groups are on the same side of the double bond and so also the H atoms. However, in trans-but-2-ene, the –CH3 groups lie on opposite sides of the double bond and so also the H atoms. For that reason, the two are not superimposable with each other. If you carry the model of cis-but-2-ene and try to overlap with trans-but-2-ene for the purpose of matching of groups and atoms, what do you find ? Are the two superimposable ? When one –CH3 group matches, the other not. When one –H atom matches, the other not. Thus the structures are non-superimposble. This kind of stereoisomerism is called Geometrical Isomerism(now-a-days called E-Z isomersm), because the geometrical relationsip between groups are different.