Recent Studies on the Aromaticity and Antiaromaticity of Planar Cyclooctatetraene
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Transport of Dangerous Goods
ST/SG/AC.10/1/Rev.16 (Vol.I) Recommendations on the TRANSPORT OF DANGEROUS GOODS Model Regulations Volume I Sixteenth revised edition UNITED NATIONS New York and Geneva, 2009 NOTE The designations employed and the presentation of the material in this publication do not imply the expression of any opinion whatsoever on the part of the Secretariat of the United Nations concerning the legal status of any country, territory, city or area, or of its authorities, or concerning the delimitation of its frontiers or boundaries. ST/SG/AC.10/1/Rev.16 (Vol.I) Copyright © United Nations, 2009 All rights reserved. No part of this publication may, for sales purposes, be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, electrostatic, magnetic tape, mechanical, photocopying or otherwise, without prior permission in writing from the United Nations. UNITED NATIONS Sales No. E.09.VIII.2 ISBN 978-92-1-139136-7 (complete set of two volumes) ISSN 1014-5753 Volumes I and II not to be sold separately FOREWORD The Recommendations on the Transport of Dangerous Goods are addressed to governments and to the international organizations concerned with safety in the transport of dangerous goods. The first version, prepared by the United Nations Economic and Social Council's Committee of Experts on the Transport of Dangerous Goods, was published in 1956 (ST/ECA/43-E/CN.2/170). In response to developments in technology and the changing needs of users, they have been regularly amended and updated at succeeding sessions of the Committee of Experts pursuant to Resolution 645 G (XXIII) of 26 April 1957 of the Economic and Social Council and subsequent resolutions. -
Organic Chemistry
Organic Chemistry Organic Chemistry Theory, Reactivity and Mechanisms in Modern Synthesis With a Foreword by Robert H. Grubbs Pierre Vogel Kendall N. Houk Authors All books published by Wiley-VCH are carefully produced. Neverthe- less, authors, editors, and publisher do not warrant the information con- Prof. Pierre Vogel tained in these books, including this book, to be free of errors. Readers EPFL are advised to keep in mind that statements, data, illustrations, procedu- SB-DO ral details or other items may inadvertently be inaccurate. Avenue F.-A. Forel 2 1015 Lausanne Library of Congress Card No.: Switzerland applied for Prof. Kendall N. Houk British Library Cataloguing-in-Publication Data Dept. of Chemistry and Biochemistry A catalogue record for this book is available from the British Library. University of California Los Angeles, CA 90095–1569 Bibliographic information published by United States the Deutsche Nationalbibliothek The Deutsche Nationalbibliothek lists this publication in the Deutsche Cover: The cover features a computed Nationalbibliografie; detailed bibliographic data are available on the transition state structure with frontier Internet at <http://dnb.d-nb.de>. molecular orbitals for the Diels-Alder reaction of SO2 and butadiene, catalyzed © 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Boschstr. 12, 69469 by another SO2 (J. Am. Chem. Soc. 1998, Weinheim, Germany 120, 13276–13277). Pierre Vogel established the mechanism of this All rights reserved (including those of translation into other languages). reaction and applied it to the total No part of this book may be reproduced in any form – by photoprinting, synthesis of natural product microfilm, or any other means – nor transmitted or translated into a (-)-dolabriferol (Angew. -
Polycyclic Aromatic Hydrocarbon Structure Index
NIST Special Publication 922 Polycyclic Aromatic Hydrocarbon Structure Index Lane C. Sander and Stephen A. Wise Chemical Science and Technology Laboratory National Institute of Standards and Technology Gaithersburg, MD 20899-0001 December 1997 revised August 2020 U.S. Department of Commerce William M. Daley, Secretary Technology Administration Gary R. Bachula, Acting Under Secretary for Technology National Institute of Standards and Technology Raymond G. Kammer, Director Polycyclic Aromatic Hydrocarbon Structure Index Lane C. Sander and Stephen A. Wise Chemical Science and Technology Laboratory National Institute of Standards and Technology Gaithersburg, MD 20899 This tabulation is presented as an aid in the identification of the chemical structures of polycyclic aromatic hydrocarbons (PAHs). The Structure Index consists of two parts: (1) a cross index of named PAHs listed in alphabetical order, and (2) chemical structures including ring numbering, name(s), Chemical Abstract Service (CAS) Registry numbers, chemical formulas, molecular weights, and length-to-breadth ratios (L/B) and shape descriptors of PAHs listed in order of increasing molecular weight. Where possible, synonyms (including those employing alternate and/or obsolete naming conventions) have been included. Synonyms used in the Structure Index were compiled from a variety of sources including “Polynuclear Aromatic Hydrocarbons Nomenclature Guide,” by Loening, et al. [1], “Analytical Chemistry of Polycyclic Aromatic Compounds,” by Lee et al. [2], “Calculated Molecular Properties of Polycyclic Aromatic Hydrocarbons,” by Hites and Simonsick [3], “Handbook of Polycyclic Hydrocarbons,” by J. R. Dias [4], “The Ring Index,” by Patterson and Capell [5], “CAS 12th Collective Index,” [6] and “Aldrich Structure Index” [7]. In this publication the IUPAC preferred name is shown in large or bold type. -
Aromaticity Sem- Ii
AROMATICITY SEM- II In 1931, German chemist and physicist Sir Erich Hückel proposed a theory to help determine if a planar ring molecule would have aromatic properties .This is a very popular and useful rule to identify aromaticity in monocyclic conjugated compound. According to which a planar monocyclic conjugated system having ( 4n +2) delocalised (where, n = 0, 1, 2, .....) electrons are known as aromatic compound . For example: Benzene, Naphthalene, Furan, Pyrrole etc. Criteria for Aromaticity 1) The molecule is cyclic (a ring of atoms) 2) The molecule is planar (all atoms in the molecule lie in the same plane) 3) The molecule is fully conjugated (p orbitals at every atom in the ring) 4) The molecule has 4n+2 π electrons (n=0 or any positive integer Why 4n+2π Electrons? According to Hückel's Molecular Orbital Theory, a compound is particularly stable if all of its bonding molecular orbitals are filled with paired electrons. - This is true of aromatic compounds, meaning they are quite stable. - With aromatic compounds, 2 electrons fill the lowest energy molecular orbital, and 4 electrons fill each subsequent energy level (the number of subsequent energy levels is denoted by n), leaving all bonding orbitals filled and no anti-bonding orbitals occupied. This gives a total of 4n+2π electrons. - As for example: Benzene has 6π electrons. Its first 2π electrons fill the lowest energy orbital, and it has 4π electrons remaining. These 4 fill in the orbitals of the succeeding energy level. The criteria for Antiaromaticity are as follows: 1) The molecule must be cyclic and completely conjugated 2) The molecule must be planar. -
An Indicator of Triplet State Baird-Aromaticity
inorganics Article The Silacyclobutene Ring: An Indicator of Triplet State Baird-Aromaticity Rabia Ayub 1,2, Kjell Jorner 1,2 ID and Henrik Ottosson 1,2,* 1 Department of Chemistry—BMC, Uppsala University, Box 576, SE-751 23 Uppsala, Sweden; [email protected] (R.A.); [email protected] (K.J.) 2 Department of Chemistry-Ångström Laboratory Uppsala University, Box 523, SE-751 20 Uppsala, Sweden * Correspondence: [email protected]; Tel.: +46-18-4717476 Received: 23 October 2017; Accepted: 11 December 2017; Published: 15 December 2017 Abstract: Baird’s rule tells that the electron counts for aromaticity and antiaromaticity in the first ππ* triplet and singlet excited states (T1 and S1) are opposite to those in the ground state (S0). Our hypothesis is that a silacyclobutene (SCB) ring fused with a [4n]annulene will remain closed in the T1 state so as to retain T1 aromaticity of the annulene while it will ring-open when fused to a [4n + 2]annulene in order to alleviate T1 antiaromaticity. This feature should allow the SCB ring to function as an indicator for triplet state aromaticity. Quantum chemical calculations of energy and (anti)aromaticity changes along the reaction paths in the T1 state support our hypothesis. The SCB ring should indicate T1 aromaticity of [4n]annulenes by being photoinert except when fused to cyclobutadiene, where it ring-opens due to ring-strain relief. Keywords: Baird’s rule; computational chemistry; excited state aromaticity; Photostability 1. Introduction Baird showed in 1972 that the rules for aromaticity and antiaromaticity of annulenes are reversed in the lowest ππ* triplet state (T1) when compared to Hückel’s rule for the electronic ground state (S0)[1–3]. -
1 Vita Peter J. Stang Personal Data
VITA PETER J. STANG PERSONAL DATA: BORN: November 17, 1941, Nurnberg, Germany CITIZENSHIP: U.S.A. (Naturalized, June, 1962) MARRIED: 1969, Christine M.E. Schirmer CHILDREN: Antonia (b. 1973); B.S. Brown Univ. 1995; M.D. and MBA McGill Univ. 2001 Alexandra (b. 1977); Honors B.S. Univ. of Utah 2000 ADDRESS: 1406 S Chancellor Way, Salt Lake City, Utah 84108 Chemistry Department, 315 S 1400 E, Rm. 2020, University of Utah, Salt Lake City, Utah 84112 PHONE: Office – (801) 581-8329; Home – (801) 581-9749; FAX: Office – (801) 581-8433 EDUCATION B.S. Chemistry, 1963, DePaul University, Chicago, Illinois (Magna Cum Laude) Ph.D., Chemistry, 1966, University of California, Berkeley (NIH Fellow, with A. Streitwieser) Postdoctoral, 1966-68, Princeton University (NIH Fellow, with P.v.R. Schleyer) ACADEMIC EXPERIENCE David P. Gardner Chair of Chemistry, 2014-present Distinguished Professor of Chemistry, University of Utah, 1992-present Dean, College of Science, University of Utah, 1997-2007 Chairperson, Department of Chemistry, University of Utah, 1989-1995 Professor, University of Utah, 1979-1992 Honorary Professor of Chemistry, CAS Institute of Chemistry, Beijing, China Honorary Professor, Zhejiang Univ., East China Normal Univ. and East China Univ. of Science and Technology, Soochow University, Nanjing Normal University, University of Science & Technology of China Senior Fellow, Loker Hydrocarbon Research Inst., U. of Southern Calif. 1991-Present Visiting Scientist, MIT, Cambridge, Mass., 1978 Associate Professor, University of Utah, 1975-79 Assistant Professor, University of Utah, 1969-75 Instructor, Princeton University, 1968-69 RESEARCH INTERESTS Molecular Architecture via Coordination: Formation of discrete supramolecular species with well defined geometries and shapes via self-assembly (molecular triangles, squares, rectangles, pentagons, hexagons, 3D assemblies). -
Cycloalkanes, Cycloalkenes, and Cycloalkynes
CYCLOALKANES, CYCLOALKENES, AND CYCLOALKYNES any important hydrocarbons, known as cycloalkanes, contain rings of carbon atoms linked together by single bonds. The simple cycloalkanes of formula (CH,), make up a particularly important homologous series in which the chemical properties change in a much more dramatic way with increasing n than do those of the acyclic hydrocarbons CH,(CH,),,-,H. The cyclo- alkanes with small rings (n = 3-6) are of special interest in exhibiting chemical properties intermediate between those of alkanes and alkenes. In this chapter we will show how this behavior can be explained in terms of angle strain and steric hindrance, concepts that have been introduced previously and will be used with increasing frequency as we proceed further. We also discuss the conformations of cycloalkanes, especially cyclo- hexane, in detail because of their importance to the chemistry of many kinds of naturally occurring organic compounds. Some attention also will be paid to polycyclic compounds, substances with more than one ring, and to cyclo- alkenes and cycloalkynes. 12-1 NOMENCLATURE AND PHYSICAL PROPERTIES OF CYCLOALKANES The IUPAC system for naming cycloalkanes and cycloalkenes was presented in some detail in Sections 3-2 and 3-3, and you may wish to review that ma- terial before proceeding further. Additional procedures are required for naming 446 12 Cycloalkanes, Cycloalkenes, and Cycloalkynes Table 12-1 Physical Properties of Alkanes and Cycloalkanes Density, Compounds Bp, "C Mp, "C diO,g ml-' propane cyclopropane butane cyclobutane pentane cyclopentane hexane cyclohexane heptane cycloheptane octane cyclooctane nonane cyclononane "At -40". bUnder pressure. polycyclic compounds, which have rings with common carbons, and these will be discussed later in this chapter. -
Alkenes and Alkynes
02/21/2019 CHAPTER FOUR Alkenes and Alkynes H N O I Cl C O C O Cl F3C C Cl C Cl Efavirenz Haloprogin (antiviral, AIDS therapeutic) (antifungal, antiseptic) Chapter 4 Table of Content * Unsaturated Hydrocarbons * Introduction and hybridization * Alkenes and Alkynes * Benzene and Phenyl groups * Structure of Alkenes, cis‐trans Isomerism * Nomenclature of Alkenes and Alkynes * Configuration cis/trans, and cis/trans Isomerism * Configuration E/Z * Physical Properties of Hydrocarbons * Acid‐Base Reactions of Hydrocarbons * pka and Hybridizations 1 02/21/2019 Unsaturated Hydrocarbons • Unsaturated Hydrocarbon: A hydrocarbon that contains one or more carbon‐carbon double or triple bonds or benzene‐like rings. – Alkene: contains a carbon‐carbon double bond and has the general formula CnH2n. – Alkyne: contains a carbon‐carbon triple bond and has the general formula CnH2n‐2. Introduction Alkenes ● Hydrocarbons containing C=C ● Old name: olefins • Steroids • Hormones • Biochemical regulators 2 02/21/2019 • Alkynes – Hydrocarbons containing C≡C – Common name: acetylenes Unsaturated Hydrocarbons • Arene: benzene and its derivatives (Ch 9) 3 02/21/2019 Benzene and Phenyl Groups • We do not study benzene and its derivatives until Chapter 9. – However, we show structural formulas of compounds containing a phenyl group before that time. – The phenyl group is not reactive under any of the conditions we describe in chapters 5‐8. Structure of Alkenes • The two carbon atoms of a double bond and the four atoms bonded to them lie in a plane, with bond angles of approximately 120°. 4 02/21/2019 Structure of Alkenes • Figure 4.1 According to the orbital overlap model, a double bond consists of one bond formed by overlap of sp2 hybrid orbitals and one bond formed by overlap of parallel 2p orbitals. -
Aromaticity, Antiaromaticity, Homoaromaticity and the Hückel (4N + 2) Rule
See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/329877657 Aromaticity, Antiaromaticity, Homoaromaticity and the Hückel (4n + 2) Rule Presentation · December 2018 DOI: 10.13140/RG.2.2.34131.63528 CITATIONS READS 0 36,125 1 author: Dr Sumanta Mondal GITAM (Deemed to be University) 259 PUBLICATIONS 510 CITATIONS SEE PROFILE Some of the authors of this publication are also working on these related projects: SARS-CoV-2 View project Natural Products View project All content following this page was uploaded by Dr Sumanta Mondal on 10 May 2021. The user has requested enhancement of the downloaded file. Aromaticity, Antiaromaticity and the Hückel (4n + 2) Rule ❖ Aromaticity - In 1931, German chemist and physicist Sir Erich Hückel proposed a theory to help determine if a planar ring molecule would have aromatic properties. His rule states that if a cyclic, planar molecule has 4n+2 π electrons, it is considered aromatic. This rule would come to be known as Hückel's Rule. • Criteria for Aromaticity 1) The molecule is cyclic (a ring of atoms) 2) The molecule is planar (all atoms in the molecule lie in the same plane) 3) The molecule is fully conjugated (p orbitals at every atom in the ring) 4) The molecule has 4n+2 π electrons (n=0 or any positive integer) • Why 4n+2 π Electrons? - According to Hückel's Molecular Orbital Theory, a compound is particularly stable if all of its bonding molecular orbitals are filled with paired electrons. - This is true of aromatic compounds, meaning they are quite stable. -
WO 2016/074683 Al 19 May 2016 (19.05.2016) W P O P C T
(12) INTERNATIONAL APPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY (PCT) (19) World Intellectual Property Organization International Bureau (10) International Publication Number (43) International Publication Date WO 2016/074683 Al 19 May 2016 (19.05.2016) W P O P C T (51) International Patent Classification: (81) Designated States (unless otherwise indicated, for every C12N 15/10 (2006.01) kind of national protection available): AE, AG, AL, AM, AO, AT, AU, AZ, BA, BB, BG, BH, BN, BR, BW, BY, (21) International Application Number: BZ, CA, CH, CL, CN, CO, CR, CU, CZ, DE, DK, DM, PCT/DK20 15/050343 DO, DZ, EC, EE, EG, ES, FI, GB, GD, GE, GH, GM, GT, (22) International Filing Date: HN, HR, HU, ID, IL, IN, IR, IS, JP, KE, KG, KN, KP, KR, 11 November 2015 ( 11. 1 1.2015) KZ, LA, LC, LK, LR, LS, LU, LY, MA, MD, ME, MG, MK, MN, MW, MX, MY, MZ, NA, NG, NI, NO, NZ, OM, (25) Filing Language: English PA, PE, PG, PH, PL, PT, QA, RO, RS, RU, RW, SA, SC, (26) Publication Language: English SD, SE, SG, SK, SL, SM, ST, SV, SY, TH, TJ, TM, TN, TR, TT, TZ, UA, UG, US, UZ, VC, VN, ZA, ZM, ZW. (30) Priority Data: PA 2014 00655 11 November 2014 ( 11. 1 1.2014) DK (84) Designated States (unless otherwise indicated, for every 62/077,933 11 November 2014 ( 11. 11.2014) US kind of regional protection available): ARIPO (BW, GH, 62/202,3 18 7 August 2015 (07.08.2015) US GM, KE, LR, LS, MW, MZ, NA, RW, SD, SL, ST, SZ, TZ, UG, ZM, ZW), Eurasian (AM, AZ, BY, KG, KZ, RU, (71) Applicant: LUNDORF PEDERSEN MATERIALS APS TJ, TM), European (AL, AT, BE, BG, CH, CY, CZ, DE, [DK/DK]; Nordvej 16 B, Himmelev, DK-4000 Roskilde DK, EE, ES, FI, FR, GB, GR, HR, HU, IE, IS, IT, LT, LU, (DK). -
(12) Patent Application Publication (10) Pub. No.: US 2007/0087223 A1 Sakamoto Et Al
US 20070087223A1. (19) United States (12) Patent Application Publication (10) Pub. No.: US 2007/0087223 A1 Sakamoto et al. (43) Pub. Date: Apr. 19, 2007 (54) DIBENZOANTHRACENE DERIVATIVES, 14-position of a dibenzoa,canthracene skeleton and repre ORGANIC ELECTROLUMNESCENT sented by the following formula (1) or (2): DEVICES, AND DISPLAY APPARATUS Formula (1) (75) Inventors: Yukinari Sakamoto, Tokyo (JP); Yoshihisa Miyabayashi, Kanagawa (JP); Tadahiko Yoshinaga, Kanagawa (JP) Correspondence Address: ROBERT. DEPKE LEWIS T. STEADMAN ROCKEY, DEPKE, LYONS AND KITZINGER, LLC SUTE 5450 SEARS TOWER CHICAGO, IL 60606-6306 (US) Formula (2) (73) Assignee: SONY CORPORATION (21) Appl. No.: 11/583,645 (22) Filed: Oct. 17, 2006 (30) Foreign Application Priority Data Oct. 19, 2005 (JP).................................... P2005-304.047 Publication Classification (51) Int. Cl. wherein X', X and X each independently represents a HOIL 5/54 (2006.01) substituted or unsubstituted arylene or divalent heterocyclic C09K II/06 (2006.01) group; A, B, C and D each independently represents a CD7C 2 II/6 (2006.01) Substituted or unsubstituted alkyl, aryl or heterocyclic group, (52) U.S. Cl. ......................... 428/690; 428/917; 313/504; and between the adjacent groups, may be fused together to 313/506; 257/E51; 257/E51; form rings; and Y' to Y''' and R' each independently rep 564/426; 564/434 resents a hydrogen or halogen atom, an alkoxy group, or a Substituted or unsubstituted alkyl, aryl or heterocyclic group, (57) ABSTRACT and, when Y to U' and R' are other than a hydrogen or Dibenzoanthracene derivatives are each substituted by an halogen atom, Y' to Y' and R' may be fused together amino compound group at at least one of 9-position and between the adjacent groups to form rings. -
Synthetic and Mechanistic Studies of 3, 3-Dimethoxycyclopropene
SYNTHETIC AND MECHANISTIC STUDIES OF 3 , 3-DIMETHOXYCYCLOPROPENE By RUDOLPH MILTON ALBERT, JR. A DISSERTATION PRESENTED TO THE GRADUATE COUNCIL OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY UNIVERSITY OF FLORIDA 1973 , This Dissertation is Dedicated to Carol and Elizabeth , Laura , Robert Rebecca and Daniel ACKNOWLEDGEMENTS I wish to express my deep appreciation to Dr. G.B. Butler for his friendship and guidance as my research director. The advice and suggestions of the other members of my supervisory committee are also acknowledged with gratitude. Hy colleagues in the laboratory made working more pleasant and for this I am grateful. A special note of thanks is extended to Dr. Richard L. Veazey for many valuable discussions and helpful suggestions. I wish also to thank the management of the Organic Chemicals Group, Glidden-Durkee Division of the SCM Corporation and especially Mr. R.P.T. Young for a very generous leave of absence which made it possible to come here at all. The patience and skill of my typist, Mrs. Jimmie McLeod, was of inestimable value in the preparation of this manuscript and I would like to give special recognition to her. Finally, I wish to give a special expression of gratitude to my family. All have sacrificed much to make the completion of this program possible and their abiding love has been a source of strength and determination. Ill TABLE OF CONTENTS Page ACKNOWLEDGEMENTS iii LIST OF TABLES vi LIST OF FIGURES vii ABSTRACT viii CHAPTER I. INTRODUCTION 1 II. STUDIES RELATED TO THE PREPARATION OF 3,3-DIMETHOXYCYCLOPROPENE 7 A.