Cycloalkanes, Cycloalkenes, and Cycloalkynes
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C9-14 Aliphatic [2-25% Aromatic] Hydrocarbon Solvents Category SIAP
CoCAM 2, 17-19 April 2012 BIAC/ICCA SIDS INITIAL ASSESSMENT PROFILE Chemical C -C Aliphatic [2-25% aromatic] Hydrocarbon Solvents Category Category 9 14 Substance Name CAS Number Stoddard solvent 8052-41-3 Chemical Names Kerosine, petroleum, hydrodesulfurized 64742-81-0 and CAS Naphtha, petroleum, hydrodesulfurized heavy 64742-82-1 Registry Solvent naphtha, petroleum, medium aliphatic 64742-88-7 Numbers Note: Substances in this category are also commonly known as mineral spirits, white spirits, or Stoddard solvent. CAS Number Chemical Description † 8052-41-3 Includes C8 to C14 branched, linear, and cyclic paraffins and aromatics (6 to 18%), <50ppmV benzene † 64742-81-0 Includes C9 to C14 branched, linear, and cyclic paraffins and aromatics (10 to Structural 25%), <100 ppmV benzene Formula † and CAS 64742-82-1 Includes C8 to C13 branched, linear, and cyclic paraffins and aromatics (15 to 25%), <100 ppmV benzene Registry † Numbers 64742-88-7 Includes C8 to C13 branched, linear, and cyclic paraffins and aromatics (14 to 20%), <50 ppmV benzene Individual category member substances are comprised of aliphatic hydrocarbon molecules whose carbon numbers range between C9 and C14; approximately 80% of the aliphatic constituents for a given substance fall within the C9-C14 carbon range and <100 ppmV benzene. In some instances, the carbon range of a test substance is more precisely defined in the test protocol. In these instances, the specific carbon range (e.g. C8-C10, C9-C10, etc.) will be specified in the SIAP. * It should be noted that other substances defined by the same CAS RNs may have boiling ranges outside the range of 143-254° C and that these substances are not covered by the category. -
Measuring and Predicting Sooting Tendencies of Oxygenates, Alkanes, Alkenes, Cycloalkanes, and Aromatics on a Unified Scale
Measuring and Predicting Sooting Tendencies of Oxygenates, Alkanes, Alkenes, Cycloalkanes, and Aromatics on a Unified Scale Dhrubajyoti D. Dasa,1, Peter St. Johnb,1, Charles S. McEnallya,∗, Seonah Kimb, Lisa D. Pfefferlea aYale University, Department of Chemical and Environmental Engineering, New Haven CT 06520 bNational Renewable Energy Laboratory, Golden CO 80401 Abstract Soot from internal combustion engines negatively affects health and climate. Soot emissions might be reduced through the expanded usage of appropriate biomass-derived fuels. Databases of sooting indices, based on measuring some aspect of sooting behavior in a standardized combustion environment, are useful in providing information on the comparative sooting tendencies of different fuels or pure compounds. However, newer biofuels have varied chemical structures including both aromatic and oxygenated functional groups, making an accurate measurement or prediction of their sooting tendency difficult. In this work, we propose a unified sooting tendency database for pure compounds, including both regular and oxygenated hydrocarbons, which is based on combining two disparate databases of yield-based sooting tendency measurements in the literature. Unification of the different databases was made possible by leveraging the greater dynamic range of the color ratio pyrometry soot diagnostic. This unified database contains a substantial number of pure compounds (≥ 400 total) from multiple categories of hydrocarbons important in modern fuels and establishes the sooting tendencies of aromatic and oxygenated hydrocarbons on the same numeric scale for the first time. Using this unified sooting tendency database, we have developed a predictive model for sooting behavior applicable to a broad range of hydrocarbons and oxygenated hydrocarbons. The model decomposes each compound into single-carbon fragments and assigns a sooting tendency contribution to each fragment based on regression against the unified database. -
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. -
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. -
Implications for Extraterrestrial Hydrocarbon Chemistry: Analysis Of
The Astrophysical Journal, 889:3 (26pp), 2020 January 20 https://doi.org/10.3847/1538-4357/ab616c © 2020. The American Astronomical Society. All rights reserved. Implications for Extraterrestrial Hydrocarbon Chemistry: Analysis of Acetylene (C2H2) and D2-acetylene (C2D2) Ices Exposed to Ionizing Radiation via Ultraviolet–Visible Spectroscopy, Infrared Spectroscopy, and Reflectron Time-of-flight Mass Spectrometry Matthew J. Abplanalp1,2 and Ralf I. Kaiser1,2 1 W. M. Keck Research Laboratory in Astrochemistry, University of Hawaii at Manoa, Honolulu, HI 96822, USA 2 Department of Chemistry, University of Hawaii at Manoa, Honolulu, HI 96822, USA Received 2019 October 4; revised 2019 December 7; accepted 2019 December 10; published 2020 January 20 Abstract The processing of the simple hydrocarbon ice, acetylene (C2H2/C2D2), via energetic electrons, thus simulating the processes in the track of galactic cosmic-ray particles penetrating solid matter, was carried out in an ultrahigh vacuum surface apparatus. The chemical evolution of the ices was monitored online and in situ utilizing Fourier transform infrared spectroscopy (FTIR) and ultraviolet–visible spectroscopy and, during temperature programmed desorption, via a quadrupole mass spectrometer with an electron impact ionization source (EI-QMS) and a reflectron time-of-flight mass spectrometer utilizing single-photon photoionization (SPI-ReTOF-MS) along with resonance-enhanced multiphoton photoionization (REMPI-ReTOF-MS). The confirmation of previous in situ studies of ethylene ice irradiation -
First Principles Prediction of Thermodynamic Properties
2 First Principles Prediction of Thermodynamic Properties Hélio F. Dos Santos and Wagner B. De Almeida NEQC: Núcleo de Estudos em Química Computacional, Departamento de Química, ICE Universidade Federal de Juiz de Fora (UFJF), Campus Universitário Martelos, Juiz de Fora LQC-MM: Laboratório de Química Computacional e Modelagem Molecular Departamento de Química, ICEx, Universidade Federal de Minas Gerais (UFMG) Campus Universitário, Pampulha, Belo Horizonte Brazil 1. Introduction The determination of the molecular structure is undoubtedly an important issue in chemistry. The knowledge of the tridimensional structure allows the understanding and prediction of the chemical-physics properties and the potential applications of the resulting material. Nevertheless, even for a pure substance, the structure and measured properties reflect the behavior of many distinct geometries (conformers) averaged by the Boltzmann distribution. In general, for flexible molecules, several conformers can be found and the analysis of the physical and chemical properties of these isomers is known as conformational analysis (Eliel, 1965). In most of the cases, the conformational processes are associated with small rotational barriers around single bonds, and this fact often leads to mixtures, in which many conformations may exist in equilibrium (Franklin & Feltkamp, 1965). Therefore, the determination of temperature-dependent conformational population is very much welcomed in conformational analysis studies carried out by both experimentalists and theoreticians. -
Comparing Models for Measuring Ring Strain of Common Cycloalkanes
The Corinthian Volume 6 Article 4 2004 Comparing Models for Measuring Ring Strain of Common Cycloalkanes Brad A. Hobbs Georgia College Follow this and additional works at: https://kb.gcsu.edu/thecorinthian Part of the Chemistry Commons Recommended Citation Hobbs, Brad A. (2004) "Comparing Models for Measuring Ring Strain of Common Cycloalkanes," The Corinthian: Vol. 6 , Article 4. Available at: https://kb.gcsu.edu/thecorinthian/vol6/iss1/4 This Article is brought to you for free and open access by the Undergraduate Research at Knowledge Box. It has been accepted for inclusion in The Corinthian by an authorized editor of Knowledge Box. Campring Models for Measuring Ring Strain of Common Cycloalkanes Comparing Models for Measuring R..ing Strain of Common Cycloalkanes Brad A. Hobbs Dr. Kenneth C. McGill Chemistry Major Faculty Sponsor Introduction The number of carbon atoms bonded in the ring of a cycloalkane has a large effect on its energy. A molecule's energy has a vast impact on its stability. Determining the most stable form of a molecule is a usefol technique in the world of chemistry. One of the major factors that influ ence the energy (stability) of cycloalkanes is the molecule's ring strain. Ring strain is normally viewed as being directly proportional to the insta bility of a molecule. It is defined as a type of potential energy within the cyclic molecule, and is determined by the level of "strain" between the bonds of cycloalkanes. For example, propane has tl1e highest ring strain of all cycloalkanes. Each of propane's carbon atoms is sp3-hybridized. -
Text Related to Segment 5.02 ©2002 Claude E. Wintner from the Previous Segment We Have the Value of the Heat of Combustion Of
Text Related to Segment 5.02 ©2002 Claude E. Wintner From the previous segment we have the value of the heat of combustion of an "unstrained" methylene unit as -157.4 kcal/mole. On this basis one would predict that combustion of "unstrained" cyclopropane should liberate 3 X 157.4 = 472.2 kcal/mole; however, when cyclopropane is burned, a value of 499.8 kcal/mole is measured for the actual heat of combustion. The difference of 27.6 kcal/mole is interpreted as representing the higher internal energy ("strain energy") of real cyclopropane as compared to a postulated strain-free "model." ("Model" in this usage speaks of a proposal, or postulate.) These facts are graphed conveniently on an energy diagram as follows: "Strain Energy" represents the error units: kcal/mole not to scale in the "strain-free model" real cyclopropane + 4.5 O2 27.6 "strain-free model" of cyclopropane 499.8 observed heat of combustion + 4.5 O2 472.2 3CO2 + 3H2O heat of combustion predicted for "strain-free model" Note that this estimate of the strain energy in cyclopropane amounts to 9.2 kcal/mole of strain per methylene group (dividing 27.6 by 3, because of the three carbon atoms). Comparable values in kcal/mole for other small and medium rings are given in the following table. As one might expect, in general the strain decreases as the ring is enlarged. units: kcal/mole n Total Strain Strain per CH2 3 27.6 9.2 (CH2)n 4 26.3 6.6 5 6.2 1.2 6 0.1 0.0 ! 7 6.2 0.9 8 9.7 1.2 9 12.6 1.4 10 12.4 1.2 12 4.1 0.3 15 1.9 0.1 Without entering into a discussion of the relevant bonding concepts here, and instead relying on geometry alone, interpretation of the source of the strain energy in cyclopropane and cyclobutane is to some extent self-evident. -
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]. -
Annex XV Report
Annex XV report PROPOSAL FOR IDENTIFICATION OF A SUBSTANCE OF VERY HIGH CONCERN ON THE BASIS OF THE CRITERIA SET OUT IN REACH ARTICLE 57 Substance Name(s): 1,6,7,8,9,14,15,16,17,17,18,18- Dodecachloropentacyclo[12.2.1.16,9.02,13.05,10]octadeca-7,15-diene (“Dechlorane Plus”TM) [covering any of its individual anti- and syn-isomers or any combination thereof] EC Number(s): 236-948-9; -; - CAS Number(s): 13560-89-9; 135821-74-8; 135821-03-3 Submitted by: United Kingdom Date: 29 August 2017 ANNEX XV – IDENTIFICATION OF DECHLORANE PLUS AS SVHC CONTENTS PROPOSAL FOR IDENTIFICATION OF A SUBSTANCE OF VERY HIGH CONCERN ON THE BASIS OF THE CRITERIA SET OUT IN REACH ARTICLE 57..........................................................................................IV PART I ...............................................................................................................................................1 JUSTIFICATION ..................................................................................................................................1 1. IDENTITY OF THE SUBSTANCE AND PHYSICAL AND CHEMICAL PROPERTIES ...................................2 1.1 Name and other identifiers of the substance................................................................................2 1.2 Composition of the substance ........................................................................................................2 1.3 Identity and composition of degradation products/metabolites relevant for the SVHC assessment ....................................................................................................................................3 -
Stabilization of Anti-Aromatic and Strained Five-Membered Rings with A
ARTICLES PUBLISHED ONLINE: 23 JUNE 2013 | DOI: 10.1038/NCHEM.1690 Stabilization of anti-aromatic and strained five-membered rings with a transition metal Congqing Zhu1, Shunhua Li1,MingLuo1, Xiaoxi Zhou1, Yufen Niu1, Minglian Lin2, Jun Zhu1,2*, Zexing Cao1,2,XinLu1,2, Tingbin Wen1, Zhaoxiong Xie1,Paulv.R.Schleyer3 and Haiping Xia1* Anti-aromatic compounds, as well as small cyclic alkynes or carbynes, are particularly challenging synthetic goals. The combination of their destabilizing features hinders attempts to prepare molecules such as pentalyne, an 8p-electron anti- aromatic bicycle with extremely high ring strain. Here we describe the facile synthesis of osmapentalyne derivatives that are thermally viable, despite containing the smallest angles observed so far at a carbyne carbon. The compounds are characterized using X-ray crystallography, and their computed energies and magnetic properties reveal aromatic character. Hence, the incorporation of the osmium centre not only reduces the ring strain of the parent pentalyne, but also converts its Hu¨ckel anti-aromaticity into Craig-type Mo¨bius aromaticity in the metallapentalynes. The concept of aromaticity is thus extended to five-membered rings containing a metal–carbon triple bond. Moreover, these metal–aromatic compounds exhibit unusual optical effects such as near-infrared photoluminescence with particularly large Stokes shifts, long lifetimes and aggregation enhancement. romaticity is a fascinating topic that has long interested Results and discussion both experimentalists and theoreticians because of its ever- Synthesis, characterization and reactivity of osmapentalynes. Aincreasing diversity1–5. The Hu¨ckel aromaticity rule6 applies Treatment of complex 1 (ref. 32) with methyl propiolate to cyclic circuits of 4n þ 2 mobile electrons, but Mo¨bius topologies (HC;CCOOCH3) at room temperature produced osmapentalyne favour 4n delocalized electron counts7–10. -
Chapter 2: Alkanes Alkanes from Carbon and Hydrogen
Chapter 2: Alkanes Alkanes from Carbon and Hydrogen •Alkanes are carbon compounds that contain only single bonds. •The simplest alkanes are hydrocarbons – compounds that contain only carbon and hydrogen. •Hydrocarbons are used mainly as fuels, solvents and lubricants: H H H H H H H H H H H H C H C C H C C C C H H C C C C C H H H C C H H H H H H CH2 H CH3 H H H H CH3 # of carbons boiling point range Use 1-4 <20 °C fuel (gasses such as methane, propane, butane) 5-6 30-60 solvents (petroleum ether) 6-7 60-90 solvents (ligroin) 6-12 85-200 fuel (gasoline) 12-15 200-300 fuel (kerosene) 15-18 300-400 fuel (heating oil) 16-24 >400 lubricating oil, asphalt Hydrocarbons Formula Prefix Suffix Name Structure H CH4 meth- -ane methane H C H H C H eth- -ane ethane 2 6 H3C CH3 C3H8 prop- -ane propane C4H10 but- -ane butane C5H12 pent- -ane pentane C6H14 hex- -ane hexane C7H16 hept- -ane heptane C8H18 oct- -ane octane C9H20 non- -ane nonane C10H22 dec- -ane decane Hydrocarbons Formula Prefix Suffix Name Structure H CH4 meth- -ane methane H C H H H H C2H6 eth- -ane ethane H C C H H H H C H prop- -ane propane 3 8 H3C C CH3 or H H H C H 4 10 but- -ane butane H3C C C CH3 or H H H C H 4 10 but- -ane butane? H3C C CH3 or CH3 HydHrydorcocaarrbobnos ns Formula Prefix Suffix Name Structure H CH4 meth- -ane methane H C H H H H C2H6 eth- -ane ethane H C C H H H H C3H8 prop- -ane propane H3C C CH3 or H H H C H 4 10 but- -ane butane H3C C C CH3 or H H H C H 4 10 but- -ane iso-butane H3C C CH3 or CH3 HydHrydoroccarbrobnsons Formula Prefix Suffix Name Structure H H