High Performance Using Bifunctional a Review Liquid Chromatography
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Retention Indices for Frequently Reported Compounds of Plant Essential Oils
Retention Indices for Frequently Reported Compounds of Plant Essential Oils V. I. Babushok,a) P. J. Linstrom, and I. G. Zenkevichb) National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA (Received 1 August 2011; accepted 27 September 2011; published online 29 November 2011) Gas chromatographic retention indices were evaluated for 505 frequently reported plant essential oil components using a large retention index database. Retention data are presented for three types of commonly used stationary phases: dimethyl silicone (nonpolar), dimethyl sili- cone with 5% phenyl groups (slightly polar), and polyethylene glycol (polar) stationary phases. The evaluations are based on the treatment of multiple measurements with the number of data records ranging from about 5 to 800 per compound. Data analysis was limited to temperature programmed conditions. The data reported include the average and median values of retention index with standard deviations and confidence intervals. VC 2011 by the U.S. Secretary of Commerce on behalf of the United States. All rights reserved. [doi:10.1063/1.3653552] Key words: essential oils; gas chromatography; Kova´ts indices; linear indices; retention indices; identification; flavor; olfaction. CONTENTS 1. Introduction The practical applications of plant essential oils are very 1. Introduction................................ 1 diverse. They are used for the production of food, drugs, per- fumes, aromatherapy, and many other applications.1–4 The 2. Retention Indices ........................... 2 need for identification of essential oil components ranges 3. Retention Data Presentation and Discussion . 2 from product quality control to basic research. The identifi- 4. Summary.................................. 45 cation of unknown compounds remains a complex problem, in spite of great progress made in analytical techniques over 5. -
Precursors and Chemicals Frequently Used in the Illicit Manufacture of Narcotic Drugs and Psychotropic Substances 2017
INTERNATIONAL NARCOTICS CONTROL BOARD Precursors and chemicals frequently used in the illicit manufacture of narcotic drugs and psychotropic substances 2017 EMBARGO Observe release date: Not to be published or broadcast before Thursday, 1 March 2018, at 1100 hours (CET) UNITED NATIONS CAUTION Reports published by the International Narcotics Control Board in 2017 The Report of the International Narcotics Control Board for 2017 (E/INCB/2017/1) is supplemented by the following reports: Narcotic Drugs: Estimated World Requirements for 2018—Statistics for 2016 (E/INCB/2017/2) Psychotropic Substances: Statistics for 2016—Assessments of Annual Medical and Scientific Requirements for Substances in Schedules II, III and IV of the Convention on Psychotropic Substances of 1971 (E/INCB/2017/3) Precursors and Chemicals Frequently Used in the Illicit Manufacture of Narcotic Drugs and Psychotropic Substances: Report of the International Narcotics Control Board for 2017 on the Implementation of Article 12 of the United Nations Convention against Illicit Traffic in Narcotic Drugs and Psychotropic Substances of 1988 (E/INCB/2017/4) The updated lists of substances under international control, comprising narcotic drugs, psychotropic substances and substances frequently used in the illicit manufacture of narcotic drugs and psychotropic substances, are contained in the latest editions of the annexes to the statistical forms (“Yellow List”, “Green List” and “Red List”), which are also issued by the Board. Contacting the International Narcotics Control Board The secretariat of the Board may be reached at the following address: Vienna International Centre Room E-1339 P.O. Box 500 1400 Vienna Austria In addition, the following may be used to contact the secretariat: Telephone: (+43-1) 26060 Fax: (+43-1) 26060-5867 or 26060-5868 Email: [email protected] The text of the present report is also available on the website of the Board (www.incb.org). -
Bifunctional Molecular Catalysts with Cooperating Amine/Amido Ligands
No.147 No.147 Bifunctional Molecular Catalysts with Cooperating Amine/Amido Ligands Yoshihito Kayaki and Takao Ikariya* Department of Applied Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology, 2-12-1-E4-1 O-okayama, Meguro-ku, Tokyo, 152-8552, Japan E-mail: [email protected] 1. Introduction and a coordinatively saturated hydrido(amine)ruthenium complex are involved in the catalytic cycle as depicted in The chemistry of transition metal-based molecular Figure 1. The amido complex has sufficient Brønsted basicity catalysts has progressed with discoveries of novel catalytic to dehydrogenate readily secondary alcohols including transformations as well as understanding the reaction 2-propanol to produce the hydrido(amine) complex. The NH mechanisms. Particularly, significant efforts have been unit bound to the metal center in the amine complex exhibits continuously paid to develop bifunctional molecular catalysts a sufficiently acidic character to activate ketonic substrates. having the combination of two or more active sites working in During the interconversion between the amido and the amine concert, to attain highly efficient molecular transformation for complexes, the metal/NH moiety cooperatively assists the organic synthesis. We have recently developed metal–ligand hydrogen delivery via a cyclic transition state where H– and cooperating bifunctional catalysts (concerto catalysts), in which H+ equivalents are transferred in a concerted manner from the the non-innocent ligands directly participate in the substrate hydrido(amine) complex to the C=O linkage or from 2-propanol activation and the bond formation. The concept of bifunctional to the amido complex without direct coordination to the metal molecular catalysis is now an attractive and general strategy to center (outer-sphere mechanism). -
Application of Biomarker Compounds As Tracers for Sources and Fates of Natural and Anthropogenic Organic Matter in Tile Environment
AN ABSTRACT OF THE DISSERTATION OF Daniel R. Oros for the degree of Doctor of Philosophy in Environmental Sciences presented on September 24. 1999. Title: Application of Biomarker Compoundsas Tracers for Sources and Fates of Natural and Anthropogenic Organic Matter in the Environment. Redacted for Privacy Abstract approved: Bernd R.T. Simoneit Determination of the source and fate of natural (higher plant lipids, marine lipids, etc.) and anthropogenically (e.g., petroleum, coal emissions) derived hydrocarbons and oxygenated compounds in the environment was accomplished using gas chromatography (GC) and gas chromatography-mass spectrometry (GC- MS) to characterize or identify molecular biomarkers to be utilized as tracers. The distributions and abundances of biomarkers such as straight chain homologous series (e.g., n-alkanes, n-alkanoic acids, n-alkan-2-ones, n-alkanols, etc.) and cyclic terpenoid compounds (e.g., sesquiterpenoids, diterpenoids, steroids, triterpenoids) were identified in epicuticular waxes from conifers of western North America (natural emissions). These biomarkers and their thermal alteration derivativeswere also identified in smoke emissions from known vegetation sources (e.g., conifers, deciduous trees and grasses) and were then applied as tracers in soils, soils that contained wildfire residues and soillriver mud washout after wildfire burning. Where possible, the reaction pathways of transformation from the parentprecursor compounds to intermediate and final alteration products were determined from GC- MS data. In addition, molecular tracer analysis was applied to air, water and sediment samples collected from a lacustrine setting (Crater Lake, OR) in order to determine the identities, levels and fates of anthropogenic (i.e., petroleum hydrocarbon contamination from boating and related activities) hydrocarbons ina pristine organic matter sink. -
Organocatalytic Asymmetric N-Sulfonyl Amide C-N Bond Activation to Access Axially Chiral Biaryl Amino Acids
ARTICLE https://doi.org/10.1038/s41467-020-14799-8 OPEN Organocatalytic asymmetric N-sulfonyl amide C-N bond activation to access axially chiral biaryl amino acids Guanjie Wang1, Qianqian Shi2, Wanyao Hu1, Tao Chen1, Yingying Guo1, Zhouli Hu1, Minghua Gong1, ✉ ✉ ✉ Jingcheng Guo1, Donghui Wei 2 , Zhenqian Fu 1,3 & Wei Huang1,3 1234567890():,; Amides are among the most fundamental functional groups and essential structural units, widely used in chemistry, biochemistry and material science. Amide synthesis and trans- formations is a topic of continuous interest in organic chemistry. However, direct catalytic asymmetric activation of amide C-N bonds still remains a long-standing challenge due to high stability of amide linkages. Herein, we describe an organocatalytic asymmetric amide C-N bonds cleavage of N-sulfonyl biaryl lactams under mild conditions, developing a general and practical method for atroposelective construction of axially chiral biaryl amino acids. A structurally diverse set of axially chiral biaryl amino acids are obtained in high yields with excellent enantioselectivities. Moreover, a variety of axially chiral unsymmetrical biaryl organocatalysts are efficiently constructed from the resulting axially chiral biaryl amino acids by our present strategy, and show competitive outcomes in asymmetric reactions. 1 Key Laboratory of Flexible Electronics & Institute of Advanced Materials, Jiangsu National Synergetic Innovation Center for Advanced Materials, Nanjing Tech University, 30 South Puzhu Road, Nanjing 211816, China. 2 College -
2-Alkenes from 1-Alkenes Using Bifunctional Ruthenium Catalysts
Article Cite This: Org. Process Res. Dev. 2018, 22, 1672−1682 pubs.acs.org/OPRD Catalyst versus Substrate Control of Forming (E)‑2-Alkenes from 1‑Alkenes Using Bifunctional Ruthenium Catalysts Erik R. Paulson, Esteban Delgado, III, Andrew L. Cooksy, and Douglas B. Grotjahn* San Diego State University, 5500 Campanile Drive, San Diego, California 92182-1030, United States *S Supporting Information ABSTRACT: Here we examine in detail two catalysts for their ability to selectively convert 1-alkenes to (E)-2-alkenes while κ2 + limiting overisomerization to 3- or 4-alkenes. Catalysts 1 and 3 are composed of the cations CpRu( -PN)(CH3CN) and * κ2 + − Cp Ru( -PN) , respectively (where PN is a bifunctional phosphine ligand), and the anion PF6 . Kinetic modeling of the fi reactions of six substrates with 1 and 3 generated rst- and second-order rate constants k1 and k2 (and k3 when applicable) that represent the rates of reaction for conversion of 1-alkene to (E)-2-alkene (k1), (E)-2-alkene to (E)-3-alkene (k2), and so on. The k1:k2 ratios were calculated to produce a measure of selectivity for each catalyst toward monoisomerization with each substrate. fi The k1:k2 values for 1 with the six substrates range from 32 to 132. The k1:k2 values for 3 are signi cantly more substrate- dependent, ranging from 192 to 62 000 for all of the substrates except 5-hexen-2-one, for which the k1:k2 value was only 4.7. Comparison of the ratios for 1 and 3 for each substrate shows a 6−12-fold greater selectivity using 3 on the three linear substrates as well as a >230-fold increase for 5-methylhex-1-ene and a 44-fold increase for a silyl-protected 4-penten-1-ol substrate, which are branched three and five atoms away from the alkene, respectively. -
Direct Synthesis of Dimethyl Ether from Syngas on Bifunctional Hybrid
catalysts Article Direct Synthesis of Dimethyl Ether from Syngas on Bifunctional Hybrid Catalysts Based on Supported H3PW12O40 and Cu-ZnO(Al): Effect of Heteropolyacid Loading on Hybrid Structure and Catalytic Activity Elena Millán , Noelia Mota, Rut Guil-López, Bárbara Pawelec , José L. García Fierro and Rufino M. Navarro * Instituto de Catálisis y Petroleoquímica (CSIC), C/Marie Curie 2, Cantoblanco, 28049 Madrid, Spain; [email protected] (E.M.); [email protected] (N.M.); [email protected] (R.G.-L.); [email protected] (B.P.); jlgfi[email protected] (J.L.G.F.) * Correspondence: [email protected] Received: 27 August 2020; Accepted: 15 September 2020; Published: 17 September 2020 Abstract: The performance of bifunctional hybrid catalysts based on phosphotungstic acid (H3PW12O40, HPW) supported on TiO2 combined with Cu-ZnO(Al) catalyst in the direct synthesis of dimethyl ether (DME) from syngas has been investigated. We studied the effect of the HPW loading on TiO2 (from 1.4 to 2.7 monolayers) on the dispersion and acid characteristics of the HPW clusters. When the concentration of the heteropoliacid is slightly higher than the monolayer (1.4 monolayers) the acidity of the clusters is perturbed by the surface of titania, while for concentration higher than 1.7 monolayers results in the formation of three-dimensional HPW nanocrystals with acidity similar to the bulk heteropolyacid. Physical hybridization of supported heteropolyacids with the Cu-ZnO(Al) catalyst modifies both the acid characteristics of the supported heteropolyacids and the copper surface area of the Cu-ZnO(Al) catalyst. -
Chiral Bifunctional Phosphine Ligand Enabling Gold-Catalyzed
Communication Cite This: J. Am. Chem. Soc. 2019, 141, 3787−3791 pubs.acs.org/JACS Chiral Bifunctional Phosphine Ligand Enabling Gold-Catalyzed Asymmetric Isomerization of Alkyne to Allene and Asymmetric Synthesis of 2,5-Dihydrofuran Xinpeng Cheng, Zhixun Wang, Carlos D. Quintanilla, and Liming Zhang* Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, United States *S Supporting Information Scheme 1. Soft Propargylic Deprotonation and Chiral 2,5- ABSTRACT: The asymmetric isomerization of alkyne to Dihydrofuran Synthesis allene is the most efficient and the completely atom- economic approach to this class of versatile axial chiral structure. However, the state-of-the-art is limited to tert- butyl alk-3-ynoate substrates that possess requisite acidic propargylic C−H bonds. Reported here is a strategy based on gold catalysis that is enabled by a designed chiral bifunctional biphenyl-2-ylphosphine ligand. It permits isomerization of alkynes with nonacidic α-C−H bonds and hence offers a much-needed general solution. With chiral propargylic alcohols as substrates, 2,5-disubstituted 2,5-dihydrofurans are formed in one step in typically good yields and with good to excellent diastereoselectivities. With achiral substrates, 2,5-dihydrofurans are formed with good to excellent enantiomeric excesses. A novel center- chirality approach is developed to achieve a stereocontrol effect similar to an axial chirality in the designed chiral ligand. The mechanistic studies established that the precatalyst axial epimers are all converted into the catalytically active cationic gold catalyst owing to the fluxional axis of the latter. from https://pubs.acs.org/doi/10.1021/jacs.8b12833. -
Relationship Between Chemical Structure and the Occupational
243 Occup Environ Med: first published as 10.1136/oem.2004.016402 on 18 March 2005. Downloaded from ORIGINAL ARTICLE Relationship between chemical structure and the occupational asthma hazard of low molecular weight organic compounds J Jarvis, M J Seed, R A Elton, L Sawyer, R M Agius ............................................................................................................................... Occup Environ Med 2005;62:243–250. doi: 10.1136/oem.2004.016402 Aims: To investigate quantitatively, relationships between chemical structure and reported occupational asthma hazard for low molecular weight (LMW) organic compounds; to develop and validate a model linking asthma hazard with chemical substructure; and to generate mechanistic hypotheses that might explain the relationships. Methods: A learning dataset used 78 LMW chemical asthmagens reported in the literature before 1995, and 301 control compounds with recognised occupational exposures and hazards other than respiratory sensitisation. The chemical structures of the asthmagens and control compounds were characterised by the presence of chemical substructure fragments. Odds ratios were calculated for these fragments to determine which were associated with a likelihood of being reported as an occupational asthmagen. Logistic See end of article for regression modelling was used to identify the independent contribution of these substructures. A post-1995 authors’ affiliations set of 21 asthmagens and 77 controls were selected to externally validate the model. ...................... -
Design of Bifunctional Tetraarylphosphonium Salt Catalysts
TCIMAIL No. 183 l Spring 2020 Spring 2020 l No. 183 TCIMAIL Research Article Design of Bifunctional Tetraarylphosphonium Salt Catalysts Yasunori Toda and Hiroyuki Suga Department of Materials Chemistry, Faculty of Engineering, Shinshu University: Wakasato, Nagano-shi, Nagano 380-8553, Japan E-mail: [email protected]; [email protected] Abstract: The [3+2] reactions between epoxides and carbon dioxide proceeded effectively in the presence of bifunctional tetraarylphosphonium salt catalysts, affording the corresponding cyclic carbonates in high yields. The use of isocyanates instead of carbon dioxide was found to be efficient for the synthesis of oxazolidinones from epoxides. In addition, we have successfully developed a novel phosphonium ylide as a nucleophilic catalyst for selective acylation of primary alcohols. Keywords: organocatalyst, bifunctional catalysis, phosphonium salt, [3+2] reaction, acylation 1. Introduction 2. Bifunctional TAPS catalysis Environmentally-friendly chemical syntheses are 2-1. Catalyst design challenges desired for creating a sustainable society. In the field of catalysis development, organocatalysts have emerged as Phosphonium salts are phosphorus(V) compounds green catalysts and great progress in their use has been widely used in organic synthesis as precursors of Wittig made over the past two decades. Most organocatalysts reagents, phase transfer catalysts, ionic liquids, and other have been designed to achieve stereocontrol, especially applications.1 Tetraarylphosphonium salts (TAPS), which enantiocontrol, in asymmetric reactions, whereas there are stereoelectronically tunable, are attractive scaffolds are relatively limited numbers of reports on catalysts for organocatalysts.2 As shown in Figure 1, it is expected that enable the control of chemoselectivity intentionally that TAPS bearing a hydroxyl group on an aromatic ring in non-asymmetric reactions. -
Recommended Methods for the Identification and Analysis Of
Vienna International Centre, P.O. Box 500, 1400 Vienna, Austria Tel: (+43-1) 26060-0, Fax: (+43-1) 26060-5866, www.unodc.org RECOMMENDED METHODS FOR THE IDENTIFICATION AND ANALYSIS OF AMPHETAMINE, METHAMPHETAMINE AND THEIR RING-SUBSTITUTED ANALOGUES IN SEIZED MATERIALS (revised and updated) MANUAL FOR USE BY NATIONAL DRUG TESTING LABORATORIES Laboratory and Scientific Section United Nations Office on Drugs and Crime Vienna RECOMMENDED METHODS FOR THE IDENTIFICATION AND ANALYSIS OF AMPHETAMINE, METHAMPHETAMINE AND THEIR RING-SUBSTITUTED ANALOGUES IN SEIZED MATERIALS (revised and updated) MANUAL FOR USE BY NATIONAL DRUG TESTING LABORATORIES UNITED NATIONS New York, 2006 Note Mention of company names and commercial products does not imply the endorse- ment of the United Nations. This publication has not been formally edited. ST/NAR/34 UNITED NATIONS PUBLICATION Sales No. E.06.XI.1 ISBN 92-1-148208-9 Acknowledgements UNODC’s Laboratory and Scientific Section wishes to express its thanks to the experts who participated in the Consultative Meeting on “The Review of Methods for the Identification and Analysis of Amphetamine-type Stimulants (ATS) and Their Ring-substituted Analogues in Seized Material” for their contribution to the contents of this manual. Ms. Rosa Alis Rodríguez, Laboratorio de Drogas y Sanidad de Baleares, Palma de Mallorca, Spain Dr. Hans Bergkvist, SKL—National Laboratory of Forensic Science, Linköping, Sweden Ms. Warank Boonchuay, Division of Narcotics Analysis, Department of Medical Sciences, Ministry of Public Health, Nonthaburi, Thailand Dr. Rainer Dahlenburg, Bundeskriminalamt/KT34, Wiesbaden, Germany Mr. Adrian V. Kemmenoe, The Forensic Science Service, Birmingham Laboratory, Birmingham, United Kingdom Dr. Tohru Kishi, National Research Institute of Police Science, Chiba, Japan Dr. -
Ebinder, Reply Comment on Proposed Amendment Sand Issue
UNITED STATES DISTRICT COURT Northern District of New York 206 Federal Building 15 Henry Street Binghamton, New York 13902 Thomas J. McAvoy Senior District Judge January 3, 2017 United States Sentencing Commission One Columbus Circle, N.E. Suite 2-500 Washington, DC 2002-8002 Attention: Public Affairs To the Sentencing Commission: I write in reference to your recent request for public comment on sentencing issues involving MDMA/Ecstasy, synthetic cannabinoids (such as JWH-018 and AM-2201), and synthetic cathinones (such as Methylone, MDPV, and Mephedrone). I currently preside over a case involving methylone distribution. The Defendant retained an expert who produced a report concerning the appropriate marijuana equivalency for methylone. The government responded to that report. After considering those documents, I obtained the report of an independent expert chemist. That expert addressed the questions of substantial similarity as required by USSG '2D1.1. I would be happy to share those reports and the briefs and filings related to them with the Commission. Please contact my law clerk at the address below if you would like to have those documents forwarded to you. Sincerely, Case 1:14-cr-00232-TJM Document 53 Filed 05/24/16 Page 1 of 2 May 24, 2016 via ELECTRONIC FILING Senior Judge Thomas J. McAvoy United States District Court Northern District of New York James T. Foley Courthouse 445 Broadway Albany, New York 12207 Re: United States v. Douglas Marshall, et al Docket: 14-CR-232 Your Honor: As you are aware, this firm represents defendant Douglas Marshall in connection with the above-referenced case.