15Th European Workshop on Phosphorus Chemistry EWPC 15/2018
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A-PDF Split DEMO : Purchase from to Remove the Watermark
A-PDF Split DEMO : Purchase from www.A-PDF.com to remove the watermark Figure 7.5 (a) Transition state for E2H-syn elimination. (b) Transition state for E2H-anti elimination. (c) Transition state for E,C elimination. tion state similar to that shown in Figure 7.5~is expected, since base attacks the molecule backside to the leaving group but frontside to the /3 hydrogen. Let us now turn to the experimental results to see if these predictions are borne out in fact. It has long been known that E2H reactions normally give preferentially anti elimination. For example, reaction of meso-stilbene dibromide with potassium ethoxide gives cis-bromostilbene (Reaction 7.39), whereas reaction of the D,L-dibromide gives the trans product (Reaction 7.40).lo2 A multitude of other examples exist-see, for example, note 64 (p. 355) and note 82 (p. 362). E2H reactions do, however, give syn elimination when: (1) an H-X di- hedral angle of 0" is achievable but one of 180" is not or, put another way, H and X can become syn-periplanar but not trans-periplanar ; (2) a syn hydrogen is much more reactive than the anti ones; (3) syn elimination is favored for steric reasons; and (4) an anionic base that remains coordinated with its cation, that, in turn, is coordinated with the leaving group, is used as catalyst. The very great importance of category 4 has only begun to be fully realized in the early 1970s. lo2 P. Pfeiffer, 2. Physik. Chem. Leibrig, 48, 40 (1904). 1,2-Elimination Reactions 371 An example of category 1 is found in the observation by Brown and Liu that eliminations from the rigid ring system 44, induced by the sodium salt of 2- cyclohexylcyclohexanol in triglyme, produces norborene (98 percent) but no 2-de~teronorbornene.~~~The dihedral angle between D and tosylate is O", but Crown ether present: No Yes that between H and tosylate is 120". -
Application with the Even-Odd Rule and a Specific Periodic Table for Organic and Inorganic Atoms
Open Journal of Physical Chemistry, 2021, 11, 54-63 https://www.scirp.org/journal/ojpc ISSN Online: 2162-1977 ISSN Print: 2162-1969 First Step in Dissociation Process in the Gas Phase for Small Molecules with Neutral Atoms: Application with the Even-Odd Rule and a Specific Periodic Table for Organic and Inorganic Atoms Geoffroy Auvert Grenoble Alpes University, Grenoble, France How to cite this paper: Auvert, G. (2021) Abstract First Step in Dissociation Process in the Gas Phase for Small Molecules with Neutral Dissociations in the gas phase of small molecules have been intensively stu- Atoms: Application with the Even-Odd died and dissociation energies of various gases are available in reference Rule and a Specific Periodic Table for Or- works. Configurations of compounds before and after the dissociation are ganic and Inorganic Atoms. Open Journal of Physical Chemistry, 11, 54-63. usually known, but local charges are not defined. Building on the even-odd https://doi.org/10.4236/ojpc.2021.112003 rule, the topic of a series of previous articles by the same author, the objective of this paper is to show how it can be used to give electronic rules for dissoci- Received: March 17, 2021 Accepted: May 17, 2021 ations in gases. To this end, a specific periodic table is created and used. The Published: May 20, 2021 rules are applied to a selection of more than 30 common molecules, showing that the even-odd rule and its consequences are useful in explaining the phe- Copyright © 2021 by author(s) and nomenon of dissociation in gases. -
Nomenclature Cyclic Aliphatic Hydrocarbons Are Named By
An alicyclic compound is an organic compound that is both aliphatic and cyclic. They contain one or more all-carbon rings which may be either saturated or unsaturated, but do not have aromatic character. Alicyclic compounds may have one or more aliphatic side chains attached. The simplest alicyclic compounds are the 1. monocyclic cycloalkanes: cyclopropane, cyclobutane, cyclopentane, cyclohexane, cyclohepta ne, cyclooctane, and so on. 2. Bicyclic alkanes include bicycloundecane, decalin, and housane. 3. Polycyclic alkanes include cubane, basketane, and tetrahedrane. Spiro compounds have two or more rings that are connected through only one carbon atom. Nomenclature Cyclic aliphatic hydrocarbons are named by prefixing cyclo- to the name of the corresponding open-chain hydrocarbon having the same number of carbons as the ring. For example: Cyclopropane Cyclobutane Cyclopentane Cyclopentene Substituents on the ring- alkyl, groups, halogens- are named and their positions indicated by numbers. Chlorocyclopropane 1,1- Dimethylyclopentane 1,3-Dimethylcyclohexane CH3 CH3 Cl H3C CH3 In simple cycloalkenes and cycloalkynes the double and triply bonded carbons are considered to occupy positions 1 and 2. For example: 3-Ethylcyclopentene 1,3-Cyclohexadiene H3C For convenience, aliphatic rings are often represented by simple geometric figures: a triangle for cyclopropane, a square for cyclobutane, a pentagon for cyclopentane, a hexagon for cyclohexane and so on. It is understood that two hydrogens are located at each corner of the figure unless some other group is indicated. For example H3C cyclopentane 3-Ethylcyclopentene 1,3-Cyclopentadiene CH3 CH3 Cl CH Cyclohexane 3 1,3-Dimethylcyclohexane 2- Chloro-1-methylcyclohexane As usual alcohols are given the ending –ol, which takes priority over –ene and appears last in the name. -
New Applications of Cyclobutadiene Cycloadditions: Diversity and Target Oriented Synthesis
New Applications of Cyclobutadiene Cycloadditions: Diversity and Target Oriented Synthesis Author: Jason Joseph Marineau Persistent link: http://hdl.handle.net/2345/1741 This work is posted on eScholarship@BC, Boston College University Libraries. Boston College Electronic Thesis or Dissertation, 2010 Copyright is held by the author, with all rights reserved, unless otherwise noted. Boston College The Graduate School of Arts and Sciences Department of Chemistry NEW APPLICATIONS OF CYCLOBUTADIENE CYCLOADDITIONS: DIVERSITY AND TARGET ORIENTED SYNTHESIS a dissertation by JASON JOSEPH MARINEAU submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy December 2010 © Copyright by JASON JOSEPH MARINEAU 2010 New Applications of Cyclobutadiene Cycloadditions: Diversity and Target Oriented Synthesis Jason J. Marineau Thesis Advisor: Professor Marc. L. Snapper Abstract Cyclobutadiene cycloadditions provide rapid access to rigid polycyclic systems with high strain energy and unusual molecular geometries. Further functionalization of these systems allows entry into unexplored chemical space. A tricarbonylcyclobutadiene iron complex on solid support enables exploration of these cycloadditions in a parallel format amenable to diversity oriented synthesis. Modeling of the cycloaddition transition states with density functional calculations provides a theoretical basis for analysis of the regioselectivity observed in generation of these substituted bicyclo[2.2.0]hexene derivatives. The high strain energy accessible in cyclobutadiene cycloadducts and their derivatives renders them useful synthons for access to medium-ring natural products through ring expansion. Torilin, a guaiane sesquiterpene isolated from extracts of the fruits of Torilis japonica, exhibits a range of biological activities including testosterone 5 -reductase inhibition, hKv1.5 channel blocking, hepatoprotective, anti-inflammatory and anti-cancer effects. -
Lactide/^Caprolactone Polymerization Behavior of Monomeric Aryloxytitanatrane
698 Bull. Korean Chem. Soc. 2007, Vol. 28, No. 4 Notes Synthesis, X-ray Structure, and /-Lactide/^Caprolactone Polymerization Behavior of Monomeric Aryloxytitanatrane Sang-deok Mun, Younjin Hong, and Youngjo Kim* Department of Chemistry, Chungbuk National University, Cheongju, Chungbuk 361-763, Korea. *E-mail: 가[email protected] Received February 2, 2007 Key Words : Titanatrane, Mononuclear, Ring opening polymerization, Polylactide, Polycaprolactone The chemistry of atrane coordinated by the central nitro polymerization (ROP) of l-lactide (l-LA) or ^caprolactone gen atom as well as all three arms of deprotonated triethanol 任-CL) are now one of popular research fields in the homo amine ligand, imino-2,2',2''-triethanolate, has been inten geneous catalysis. In this regard, a new mononuclear tita- sively studied over the past few decades and its examples are natrane obtained was used as a catalyst for the ROP of l-LA now known across the periodic table.1 Most studies have and £-CL. focused on the use of main group elements such as silicon, The treatment of Ti(O-i-Pr)4 with 1 equivalent of 2,6-di- phosphorus, aluminum, and tin in the formation of atrane.1 tert-butylphenol and 1 equivalent of triethanolamine in THF In view of the well known significant number of similarities gave, after workup, novel mononuclear titanatranes 1 as in the chemistries of tin and titanium, relatively few reports orange-yellow crystals in 81% isolated yield. After recrystal have appeared concerning metallic titanatranes with a lization using toluene, 1 was used as a catalyst for making transannular N—Ti bond from bridgehead N atom in polylactide (PLA) and polycaprolactone (PCL). -
Here Science-Based Cost- Effective Pathways Forward?
Sponsors Institute of Atomic and Molecular Sciences, Academia Sinica, Taiwan PIRE-ECCI Program, UC Santa Barbara, USA Max-Planck-Gesellschaft, Germany National Science Council, Taiwan Organizing committee Dr. Kuei-Hsien Chen (IAMS, Academia Sinica, Taiwan) Dr. Susannah Scott (University of California - Santa Barbara, USA) Dr. Alec Wodtke (University of Göttingen & Max-Planck-Gesellschaft, Germany) Table of Contents General Information .............................................................................................. 1 Program for Sustainable Energy Workshop ....................................................... 3 I01 Dr. Alec M. Wodtke Beam-surface Scattering as a Probe of Chemical Reaction Dynamics at Interfaces ........................................................................................................... 7 I02 Dr. Kopin Liu Imaging the steric effects in polyatomic reactions ............................................. 9 I03 Dr. Chi-Kung Ni Energy Transfer of Highly Vibrationally Excited Molecules and Supercollisions ................................................................................................. 11 I04 Dr. Eckart Hasselbrink Energy Conversion from Catalytic Reactions to Hot Electrons in Thin Metal Heterostructures ............................................................................................... 13 I05 Dr. Jim Jr-Min Lin ClOOCl and Ozone Hole — A Catalytic Cycle that We Don’t Like ............... 15 I06 Dr. Trevor W. Hayton Nitric Oxide Reduction Mediated by a Nickel Complex -
The Chemistry of Carbene-Stabilized
THE CHEMISTRY OF CARBENE-STABILIZED MAIN GROUP DIATOMIC ALLOTROPES by MARIHAM ABRAHAM (Under the Direction of Gregory H. Robinson) ABSTRACT The syntheses and molecular structures of carbene-stabilized arsenic derivatives of 1 1 i 1 1 AsCl3 (L :AsCl3 (1); L : = :C{N(2,6- Pr2C6H3)CH}2), and As2 (L :As–As:L (2)), are presented herein. The potassium graphite reduction of 1 afforded the carbene-stabilized diarsenic complex, 2. Notably, compound 2 is the first Lewis base stabilized diatomic molecule of the Group 13–15 elements, in the formal oxidation state of zero, in the fourth period or lower of the Periodic Table. Compound 2 contains one As–As σ-bond and two lone pairs of electrons on each arsenic atom. In an effort to study the chemistry of the electron-rich compound 2, it was combined with an electron-deficient Lewis acid, GaCl3. The addition of two equivalents of GaCl3 to 2 resulted in one-electron oxidation of 2 to 1 1 •+ – •+ – give [L :As As:L ] [GaCl4] (6 [GaCl4] ). Conversely, the addition of four equivalents of GaCl3 to 2 resulted in two- electron oxidation of 2 to give 1 1 2+ – 2+ – •+ [L :As=As:L ] [GaCl4 ]2 (6 [GaCl4 ]2). Strikingly, 6 represents the first arsenic radical to be structurally characterized in the solid state. The research project also explored the reactivity of carbene-stabilized disilicon, (L1:Si=Si:L1 (7)), with borane. The reaction of 7 with BH3·THF afforded two unique compounds: one containing a parent silylene (:SiH2) unit (8), and another containing a three-membered silylene ring (9). -
Electron Transfer and Modification of Oligosilanylsilatranes and Related
This is an open access article published under a Creative Commons Attribution (CC-BY) License, which permits unrestricted use, distribution and reproduction in any medium, provided the author and source are cited. Article pubs.acs.org/Organometallics Electron Transfer and Modification of Oligosilanylsilatranes and Related Derivatives † ‡ § Mohammad Aghazadeh Meshgi, Judith Baumgartner,*, Viatcheslav V. Jouikov,*, † and Christoph Marschner*, † Institut für Anorganische Chemie, Technische Universitaẗ Graz, Stremayrgasse 9, 8010 Graz, Austria ‡ Institut für Chemie, Universitaẗ Graz, Stremayrgasse 9, 8010 Graz, Austria § UMR 6226, Chimie et Photonique Moleculaires,́ Universitéde Rennes 1, 35042 Rennes, France *S Supporting Information ABSTRACT: Several silatranyl -substituted oligosilanes were prepared starting from bis(trimethylsilyl)silatranylsilanide. Electrochemical and theoretical investigations of some oligosilanes revealed that electrooxidation occurs by formation of a short-lived cation radical. This species undergoes structural relaxation to form a pair of conformers, with endo and exo relationships with respect to the Si−N interaction. Reaction of a 1,4-disilatranyl-1,4-disilanide with 1,2- dichlorotetramethyldisilane gave a mixture of cis and trans diastereomers of a cyclohexasilane with the trans isomer showing a diminished Si−N distance. ■ INTRODUCTION along the Si−N dative bond reflects the nature of Si−N − Among hypercoordinated silicon compounds silatranes (Figure bonding. In fact the Si N bonding neither is covalent nor is − 8 1) occupy a prominent position.1 4 The suffix “atrane” was based on intermolecular charge transfer. What happens with this unusual bond upon electron withdrawal, for instance during electrooxidation, is of a great interest (for classical bonds see ref 9) but is not known so far. -
Open Dissertation Xiang Li 07032018.Pdf
The Pennsylvania State University The Graduate School Department of Chemistry MECHANOCHEMICAL SYNTHESIS OF CARBON AND CARBON NITRIDE NANOTHREAD SINGLE CRYSTALS A Dissertation in Chemistry by Xiang Li 2018 Xiang Li Submitted in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy August 2018 The dissertation of Xiang Li was reviewed and approved* by the following: John V. Badding Professor of Chemistry, Physics and Materials Science and Engineering Dissertation Advisor Chair of Committee Vincent H. Crespi Professor of Physics, Materials Science and Engineering, and Chemistry Paul S. Cremer Professor of Chemistry and Biochemistry and Molecular Biology Mauricio Terrones Professor of Physics, Chemistry and Materials Science and Engineering Thomas E. Mallouk Professor of Chemistry, Biochemistry and Molecular Biology, Physics, and Engineering Science and Mechanics Head of the Department of Chemistry *Signatures are on file in the Graduate School iii ABSTRACT Carbon nanomaterials such as fullerenes, nanotubes, and graphene have been widely studied in recent decades. Benefitting from their unique bonding, they possess extraordinary physical and chemical properties. Compared with sp2 hybridized carbon allotropes, there are significantly fewer new carbon materials dominated by sp3 bonding that have been developed. Adamantane and graphane represent the smallest unit and thinnest sheet of diamond possible, respectively. One-dimensional, mostly sp3 hybridized nanocarbon, did not yet exist in 2013, when the first synthesis of carbon nanothreads finally filled up the last remaining entry in the matrix of dimensionality and hybridization of carbon nanomaterials that year. Carbon nanothread was first made by compressing benzene to ~25 GPa in a large-volume anvil cell and slowly decompressing back to ambient pressure by an alumnus of the Badding group. -
Inorganic Chemistry for Dummies® Published by John Wiley & Sons, Inc
Inorganic Chemistry Inorganic Chemistry by Michael L. Matson and Alvin W. Orbaek Inorganic Chemistry For Dummies® Published by John Wiley & Sons, Inc. 111 River St. Hoboken, NJ 07030-5774 www.wiley.com Copyright © 2013 by John Wiley & Sons, Inc., Hoboken, New Jersey Published by John Wiley & Sons, Inc., Hoboken, New Jersey Published simultaneously in Canada No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, scanning or otherwise, except as permitted under Sections 107 or 108 of the 1976 United States Copyright Act, without either the prior written permis- sion of the Publisher, or authorization through payment of the appropriate per-copy fee to the Copyright Clearance Center, 222 Rosewood Drive, Danvers, MA 01923, (978) 750-8400, fax (978) 646-8600. Requests to the Publisher for permission should be addressed to the Permissions Department, John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030, (201) 748-6011, fax (201) 748-6008, or online at http://www.wiley. com/go/permissions. Trademarks: Wiley, the Wiley logo, For Dummies, the Dummies Man logo, A Reference for the Rest of Us!, The Dummies Way, Dummies Daily, The Fun and Easy Way, Dummies.com, Making Everything Easier, and related trade dress are trademarks or registered trademarks of John Wiley & Sons, Inc. and/or its affiliates in the United States and other countries, and may not be used without written permission. All other trade- marks are the property of their respective owners. John Wiley & Sons, Inc., is not associated with any product or vendor mentioned in this book. -
Template for Electronic Submission to ACS Journals
Understanding the role of Ti-rich domains in the stabilization of gold nanoparticles on mesoporous silica-based catalysts Alaina Moragues a, Begoña Puértolas b, Álvaro Mayoral c,d, Raúl Arenal c,d, Ana B. Hungría e, Sonia Murcia-Mascarós a, Stuart H. Taylor f, Benjamín Solsona g,*, Tomás Garcíab,*, Pedro Amorós a,* a Institut de Ciència dels Materials, Universitat de València, P.O. Box 22085, 46071 Valencia, Spain. b Instituto de Carboquímica (ICB-CSIC), C/ Miguel Luesma Castán 4, 50018 Zaragoza, Spain. c Laboratorio de Microscopias Avanzadas (LMA), Instituto de Nanociencia de Aragon (INA), Universidad de Zaragoza, Mariano Esquillor, 50018 Zaragoza, Spain. d Fundación Agencia Aragonesa para la Investigación y el Desarrollo (ARAID), María de Luna 11, 50018 Zaragoza, Spain. e Departamento de Ciencia de Materiales, Ingeniería Metalúrgica y Química Inorgánica, Universidad de Cádiz, Campus Río San Pedro, 11510 Puerto Real, Spain. f Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, CF10 3AT Cardiff, United Kingdom. g Departamento de Ingenieria Quimica, Universitat de València, Avenida de la Universitat, 46071 Valencia, Spain. *Corresponding authors at: Institut de Ciència dels Materials, Universitat de València, P.O. Box 22085, 46071 Valencia, Spain (Pedro Amorós). E-mail addresses: [email protected], [email protected], [email protected] 1 ABSTRACT The preparation and stabilization of gold nanoparticles with a precise control of size and dispersion is highly attractive for a variety of applications, and a key aspect is thermal stability of the nanoparticles. This paper focuses on understanding the effect of TiO2-based nanodomains, dispersed on mesoporous silicas, and how they control gold nanoparticle stability. -
Oxatrane Is a Parent Compound of a New Atrane Family: Crystal and Molecular Structure of Triethanolamine N Oxide Academician M
ISSN 00125008, Doklady Chemistry, 2014, Vol. 458, Part 1, pp. 172–175. © Pleiades Publishing, Ltd., 2014. Original Russian Text © M.G. Voronkov, E.A. Zel’bst, A.D. Vasil’ev, M.S. Molokeev, G.A. Kuznetsova, 2014, published in Doklady Akademii Nauk, 2014, Vol. 458, No. 3, pp. 287–290. CHEMISTRY Oxatrane Is a Parent Compound of a New Atrane Family: Crystal and Molecular Structure of Triethanolamine NOxide Academician M. G. Voronkova †, E. A. Zel’bstb, A. D. Vasil’evc,d, M. S. Molokeevc,d, and G. A. Kuznetsovaa Received March 27, 2014 DOI: 10.1134/S0012500814090031 Tertiary amine Noxides of general formula A particular interest in tertiary amine Noxides has + increased in recent years. Triethanolamine Noxide, O ⎯ NR3 (previously O=NR3 or O → NR3) continue to attract interest of synthetic, theoretical, and applied which was considered to have structure chemists. They are already used in cosmetics, as bio O=N(CH2CH2OH)3 [3], was ascribed to them by medical agents, and as oxidants in a number of organic analogy, but its molecular structure was not estab reactions (catalytic epoxidation and dihydroxylation lished. Therefore, we determined the structure by X of alkenes, catalytic oxidation of alcohols, etc.) [1, 2]. ray diffraction, presuming that the oxide oxygen atom The most general method of their synthesis is the oxi in this molecule is bound to the nitrogen atom and sur dation of tertiary amines with hydrogen peroxide, per rounded by three CH CH OH groups like hydrogen oxy acids, dioxiranes, and oxaazapyridines [1]. 2 2 atom in protatranes [4]. The obtained data proved to Triethanolamine Noxide (TEA) formulated as be unexpected and, nonetheless, allowed us to name + O –N (CH2CH2OH)3 and obtained by the oxidation TEA Noxide as oxatrane (OA) by analogy with pro of triethanolamine with hydrogen peroxide [3] is also tatranes, Fig.