DOCSLIB.ORG

C-H Borylation of Terminal Alkynes, the Reductive Cyclization

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
C-H Borylation of Terminal Alkynes, the Reductive Cyclization C-H BORYLATION OF TERMINAL ALKYNES, THE REDUCTIVE CYCLIZATION OF ALKYNYLBORONATES, AND THE SYNTHESIS AND ANALYSIS OF PINCER-LIGATED RHODIUM COMPLEXES A Dissertation by CHRISTOPHER JAMES PELL Submitted to the Office of Graduate and Professional Studies of Texas A&M University in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Chair of Committee, Oleg V. Ozerov Committee Members, Michael B. Hall Franҫois P. Gabbaї Perla B. Balbuena Head of Department, Simon W. North December 2017 Major Subject: Chemistry Copyright 2017 Christopher J. Pell ABSTRACT Due to the utility of organoboron reagents in the synthesis of pharmaceuticals and other industrially relevant compounds, the transition metal-catalyzed C-H borylation of organic molecules has become a very popular area of research. Since the Ozerov group’s initial discovery of an iridium complex that can perform catalytic dehydrogenative borylation of terminal alkynes (DHBTA), we have made further investigations into the C-H borylation of terminal alkynes and the synthetic applications of the alkynylboronate products. Here we describe a pincer-ligated palladium complex as the first group 10 catalyst for DHBTA. Unlike the iridium systems, the palladium catalyst also catalyzed a competing alkyne hydrogenation reaction, which could be suppressed using elemental mercury or phosphines as additives. We then turned our attention to (PNP)Ir complexes as catalysts for the DHBTA of 1,6-enynes and 1,6-diynes. These substrates could be borylated and isolated in moderate to excellent yields, and they could serve as substrates for rhodium-catalyzed reductive cyclization to form five-membered cyclic compounds containing pendant C-B bonds. It was found that borylated 1,6-diynes tethered by amines or an ether linkage would form 3,4-bis(methylpinacolboryl)-substituted pyrroles or furans during reductive cyclization. Investigations into C-C coupling catalyzed by pincer-ligated rhodium complexes will also be discussed. First, we describe the synthesis of a series of PCP-based pincer- ligated rhodium complexes and how they performed as catalysts for stereoselective ii alkyne dimerization. While stereoselectivity was not achieved with any of the PCP- ligands on rhodium, these systems were faster and longer-lived than the (PNP)Rh alkyne dimerization catalysts previously reported by our group. Later, the fate of (PNP)Rh as a potential catalyst for Negishi coupling will be discussed. It was observed that although (PNP)Rh could perform all three fundamental steps in Negishi coupling (oxidative addition of an aryl halide, transmetallation, and reductive elimination), it was not a suitable catalyst. This was due to rhodium’s ability to insert into the carbon-zinc bond of the organozinc reagent to form a catalytically inactive species. Finally, the synthesis, characterization, and electronic structure of complexes of (PNP)Rh bearing small perfluorocarbon ligands will be described. iii DEDICATION To Mom and Dad for showing me that hard work pays off. iv ACKNOWLEDGEMENTS I would like to thank my research advisor Dr. Oleg Ozerov for his guidance over the past five years as well as during my 2011 summer semester as an REU student. I appreciate his time and all the opportunities that he has provided me. His mentorship has allowed me to develop into a successful chemist and an independent thinker. I would also like to thank my committee members Dr. Michael Hall, Dr. François Gabbaï, and Dr. Perla Balbuena. I would also like to thank the Ozerov research group, especially my elders who mentored me in navigating graduate school and becoming a better chemist: Sam Timpa, Morgan MacInnis, Chun-I Lee, Loren Press, Billy McCulloch, Jessica DeMott, Yanjun Zhu, Rafael Huacuja, Rodrigo Ramirez, Jill Davidson, and Chandra Mouli Palit. I also appreciated having Wei-Chun Shih as a classmate, and I am proud to see Bryan Foley continue the project of alkyne C-H borylation. To all of those still working in the Ozerov group, I wish you the best of luck. Above all, I would like to thank my family who stood by me and made all of my accomplishments possible. Thanks to my mom, dad, and Tom for instilling in me all the values that have helped me succeed in graduate school. Finally, I would like to thank the love of my life, Yanyan Wang, who inspires me to be a better person. I am proud to have spent time at Texas A&M University. The spirit and traditions of A&M are contagious, and I am glad that I have become a part of this community. v CONTRIBUTORS AND FUNDING SOURCES This work was supervised by a thesis committee consisting of Professor Oleg V. Ozerov, Professor Franҫois P. Gabbaї, and Professor Michael B. Hall of the Department of Chemistry and Professor Perla B. Balbuena of the Department of Chemical Engineering. Assistance with automated flash column chromatography for the work in Chapter 3 was provided by Yanyan Wang and Professor Donald J. Darensbourgh (Department of Chemistry, TAMU). The XRD structures in Chapter 5 were solved by Wei-Chun Shih during his time as a graduate student in the Department of Chemsitry at Texas A&M Univsersity. The XRD structures in Chapter 6 were solved by David Herbert during his time as a postdoctoral research associate in the Department of Chemistry at Texas A&M University. The synthesis and characterization of some compounds in Chapter 6 were completed by Yanjun Zhu (Department of Chemsitry, TAMU), and several experiments were conducted by Rafael Huacuja (Department of Chemistry, TAMU). All computational analysis in Chapter 6 was performed by Professor Russel P. Hughes of the Department of Chemistry at Dartmouth College. All other work conducted for this dissertation was completed by the student independently. This work was made possible in part by the U.S. National Science Foundation (grants CHE-0944634, CHE-1300299, and CHE-1565923 to O. V. O.) and the Welch vi Foundation (grant A-1717 to O. V. O.). Its contents are solely the responsibility of the authors and do not necessarily represent the official views of the U.S. National Science Foundation or the Welch Foundation. vii NOMENCLATURE Ar Aryl BArF20 Tetrakis(pentafluorophenyl)borate B2pin2 Bis(pinacolato)diboron BINAP 2,2’-Bis(diphenylphosphino)-1,1’-binaphthyl BIPHEP 2,2’-Bis(diphenylphosphino)-1,1’-biphenyl Boc tert-Butoxycarbonyl CAAC Cyclic (alkyl)(amino) carbene COD Cyclooctadiene COE Cyclooctene Cp Cyclopentadienyl Cp* 1,2,3,4,5-Pentamethylcyclopentadienyl DBA Dibenzylideneacetone DFT Density Functional Theory DHBTA Dehydrogenative Borylation of Terminal Alkynes Dipp 2,6-diisopropylphenyl Et Ethyl FLP Frustrated Lewis Pair HBpin Pinacolborane, 4,4,5,5-tetramethyl-1,3,2-dioxaborolane HBdan 1,8-naphthalenediaminatoborane iPr iso-propyl MIDA N-methylimidodiacetic acid viii NBO Natural Bond Order NBS N-bromosuccinimide n-Bu n-butyl NHC N-heterocyclic carbene NLMO Natural Localized Molecular Orbitals NMR Nuclear Magnetic Resonance OA Oxidative Addition OAc Acetate OTf Triflate Ph Phenyl PMP 1,2,2,6,6-pentamethylpiperidine py pyridine RE Reductive Elimination TBE tert-butyl ethylene, 2,2-dimethyl-3-butene tBu tert-butyl THF Tetrahydrofuran TM Transmetallation Ts Toluenesulfonamide WBI Wiberg Bond Indices XRD X-Ray Diffraction ix TABLE OF CONTENTS Page ABSTRACT .......................................................................................................................ii DEDICATION .................................................................................................................. iv ACKNOWLEDGEMENTS ............................................................................................... v CONTRIBUTORS AND FUNDING SOURCES ............................................................. vi NOMENCLATURE ....................................................................................................... viii TABLE OF CONTENTS ................................................................................................... x LIST OF SCHEMES ....................................................................................................... xiv LIST OF FIGURES ......................................................................................................... xix LIST OF TABLES .........................................................................................................xxii CHAPTER I INTRODUCTION AND LITERATURE REVIEW .................................... 1 1.1 Introduction .............................................................................................................. 1 1.1.1 Introduction to Organoboron Chemistry ........................................................... 1 1.1.2 Synthesis of Organoboron Reagents and the Beginning of C-H Borylation ..... 3 1.1.3 Summary – Alkynylboronates in Context ......................................................... 7 1.2 Synthesis of Alkynylboron Compounds ................................................................ 10 1.2.1 Traditional Synthesis of Alkynylboron Reagents ........................................... 10 1.2.1.1 Synthesis of Alkynylboronates ................................................................. 10 1.2.1.2 Synthesis of Ethynyl N-Methylimidodiacetic Acid Boronates ................ 12 1.2.1.3 Synthesis of Alkynyl Trifluoroborate Salts .............................................. 13 1.2.2 Dehydrogenative Borylation of Terminal Alknyes ......................................... 13 1.2.3 Formation of Alkynyl Triarylborates with Frustrated Lewis Pairs ................. 19 1.2.4 Formation
Load more

Recommended publications
  • Electronic Structure and Crystal Phase Stability of Palladium Hydrides
    Electronic structure and crystal phase stability of palladium hydrides Abdesalem Houari∗ Theoretical Physics Laboratory, Department of Physics, University of Bejaia, Bejaia, Algeria Samir F. Matar† CNRS, ICMCB, Universit´ede Bordeaux, 33600 Pessac, France Volker Eyert‡ Materials Design SARL, 92120 Montrouge, France (Dated: November 4, 2014) The results of electronic structure calculations for a variety of palladium hydrides are presented. The calculations are based on density functional theory and used different local and semilocal approximations. The thermodynamic stability of all structures as well as the electronic and chemical bonding properties are addressed. For the monohydride, taking into account the zero-point energy is important to identify the octahedral Pd-H arrangement with its larger voids and, hence, softer hydrogen vibrational modes as favorable over the tetrahedral arrangement as found in the zincblende and wurtzite structures. Stabilization of the rocksalt structure is due to strong bonding of the 4d and 1s orbitals, which form a characteristic split-off band separated from the main d-band group. Increased filling of the formerly pure d states of the metal causes strong reduction of the density of states at the Fermi energy, which undermines possible long-range ferromagnetic order otherwise favored by strong magnetovolume effects. For the dihydride, octahedral Pd-H arrangement as realized e.g. in the pyrite structure turns out to be unstable against tetrahedral arrangemnt as found in the fluorite structure. Yet, from both heat of formation and chemical bonding considerations the dihydride turns out to be less favorable than the monohydride. Finally, the vacancy ordered defect phase Pd3H4 follows the general trend of favoring the octahedral arrangement of the rocksalt structure for Pd:H ratios less or equal to one.
    [Show full text]
  • Contemporary Organosilicon Chemistry
    Contemporary organosilicon chemistry Edited by Steve Marsden Generated on 05 October 2021, 02:13 Imprint Beilstein Journal of Organic Chemistry www.bjoc.org ISSN 1860-5397 Email: [email protected] The Beilstein Journal of Organic Chemistry is published by the Beilstein-Institut zur Förderung der Chemischen Wissenschaften. This thematic issue, published in the Beilstein Beilstein-Institut zur Förderung der Journal of Organic Chemistry, is copyright the Chemischen Wissenschaften Beilstein-Institut zur Förderung der Chemischen Trakehner Straße 7–9 Wissenschaften. The copyright of the individual 60487 Frankfurt am Main articles in this document is the property of their Germany respective authors, subject to a Creative www.beilstein-institut.de Commons Attribution (CC-BY) license. Contemporary organosilicon chemistry Steve Marsden Editorial Open Access Address: Beilstein Journal of Organic Chemistry 2007, 3, No. 4. School of Chemistry, University of Leeds, Leeds LS2 9JT, UK doi:10.1186/1860-5397-3-4 Email: Received: 06 February 2007 Steve Marsden - [email protected] Accepted: 08 February 2007 Published: 08 February 2007 © 2007 Marsden; licensee Beilstein-Institut License and terms: see end of document. Abstract Editorial for the Thematic Series on Contemporary Organosilicon Chemistry. The field of organosilicon chemistry has a rich and varied the 1990s, and equivalent to the number appearing in the much history, and has long since made the progression from chemical longer established field of organoboron chemistry
    [Show full text]
  • Herbert Charles Brown, a Biographical Memoir
    NATIONAL ACADEMY OF SCIENCES H E R B E R T Ch ARLES BROWN 1 9 1 2 — 2 0 0 4 A Biographical Memoir by E I-I CH I N EGIS HI Any opinions expressed in this memoir are those of the author and do not necessarily reflect the views of the National Academy of Sciences. Biographical Memoir COPYRIGHT 2008 NATIONAL ACADEMY OF SCIENCES WASHINGTON, D.C. Photograph Credit Here. HERBERT CHARLES BROWN May 22, 1912–December 19, 2004 BY EI -ICH I NEGISHI ERBERT CHARLES BROWN, R. B. Wetherill Research Profes- Hsor Emeritus of Purdue University and one of the truly pioneering giants in the field of organic-organometallic chemistry, died of a heart attack on December 19, 2004, at age 92. As it so happened, this author visited him at his home to discuss with him an urgent chemistry-related matter only about 10 hours before his death. For his age he appeared well, showing no sign of his sudden death the next morn- ing. His wife, Sarah Baylen Brown, 89, followed him on May 29, 2005. They were survived by their only child, Charles A. Brown of Hitachi Ltd. and his family. H. C. Brown shared the Nobel Prize in Chemistry in 1979 with G. Wittig of Heidelberg, Germany. Their pioneering explorations of boron chemistry and phosphorus chemistry, respectively, were recognized. Aside from several biochemists, including V. du Vigneaud in 1955, H. C. Brown was only the second American organic chemist to win a Nobel Prize behind R. B. Woodward, in 1965. His several most significant contribu- tions in the area of boron chemistry include (1) codiscovery of sodium borohyride (1972[1], pp.
    [Show full text]
  • Frontiers in Iridium-Catalyzed CH Borylation
    Frontiers in Iridium-Catalyzed C-H Borylation: Attaining Novel Reactivity and Selectivity By Matthew Alan Larsen A dissertation submitted in partial satisfaction of the requirements for the degree of Doctor of Philosophy in Chemistry in the Graduate Division of the University of California, Berkeley Committee in charge: Professor John F. Hartwig, Chair Professor Robert G. Bergman Professor Alexis T. Bell Fall 2016 Abstract Frontiers in Iridium-Catalyzed C-H Borylation: Attaining Novel Reactivity and Selectivity By Matthew Alan Larsen Doctor of Philosophy in Chemistry University of California, Berkeley Professor John F. Hartwig, Chair The following dissertation discusses the development of novel methodology for the catalytic borylation of C-H bonds and includes in-depth studies on the mechanism and selectivity of these synthetic transformations. These methods include the borylation of heteroaryl C-H bonds, the selective borylation of benzylic C-H bonds, and the directed and undirected borylation of unactivated alkyl C-H bonds. Chapter 1 contains a comprehensive review of C-H borylation methodology. This review focuses on the initial development of catalytic C-H borylation and on the state-of- the-art of methodology for the undirected and directed borylation of aryl, benzylic, and alkyl C-H bonds. Additionally, this review highlights knowledge gaps and unsolved challenges. Furthermore, this review provides the author’s opinion on future directions for research on the borylation of C-H bonds. Chapter 2 describes the study of the iridium-catalyzed borylation of heteroaryl C- H bonds. Contained is an examination of the scope of the borylation of heterocycles containing more than one heteroatom and rules for predicting the site-selectivity of this reaction.
    [Show full text]
  • S-Block Amidoboranes: Syntheses, Structures, Reactivity and Applications Cite This: Chem
    Chem Soc Rev View Article Online REVIEW ARTICLE View Journal | View Issue s-Block amidoboranes: syntheses, structures, reactivity and applications Cite this: Chem. Soc. Rev., 2016, 45, 1112 Tom E. Stennett and Sjoerd Harder* Metal amidoborane compounds of the alkali- and alkaline earth metals have in recent years found applications in diverse disciplines, notably as hydrogen storage materials, as reagents for the reduction of organic functional groups and as catalysts and intermediates in dehydrocoupling reactions. These functions are connected by the organometallic chemistry of the MNR2BH3 group.† This review focusses on central aspects of the s-block amidoborane compounds – their syntheses, structures and reactivity. Well-defined amidoborane complexes of group 2 metals are now available by a variety of solution-phase routes, which has allowed a more detailed analysis of this functional group, which was previously largely confined to solid-state materials chemistry. Structures obtained from X-ray crystallography have begun to provide increased understanding of the fundamental steps of key processes, including amine–borane Creative Commons Attribution 3.0 Unported Licence. dehydrocoupling and hydrogen release from primary and secondary amidoboranes. We review structural parameters and reactivity to rationalise the effects of the metal, nitrogen substituents and supporting Received 10th July 2015 ligands on catalytic performance and dehydrogenative decomposition routes. Mechanistic features of DOI: 10.1039/c5cs00544b key processes involving amidoborane compounds as starting materials or intermediates are discussed, alongside emerging applications such as the use of group 1 metal amidoboranes in synthesis. Finally, the www.rsc.org/chemsocrev future prospects of this vibrant branch of main group chemistry are evaluated.
    [Show full text]
  • Flexible Solar Cells
    Flexible Solar Cells A Major Qualifying Project Submitted to the Faculty Of Worcester Polytechnic Institute In Partial Fulfillment of the requirements for the Degree in Bachelor of Science In Mechanical Engineering By Francis LaRovere Edward Peglow Michael McMahon Project Advisor Professor Pratap Rao, Advisor This report represents work of WPI undergraduate students submitted to the faculty as evidence of a degree requirement. WPI routinely publishes these reports on its w ebsite without editorial or peer review. For more information about the projects program at WPI, see http://www.wpi.edu/Academics/Projects. 1 Table of Contents Table of Figures ............................................................................................................................................. 5 Table of Tables .............................................................................................................................................. 6 Acknowledgments ......................................................................................................................................... 7 Abstract ......................................................................................................................................................... 8 1. Introduction .............................................................................................................................................. 9 2. Scope ......................................................................................................................................................
    [Show full text]
  • UNITED STATES PATENT OFFICE 2,56,31 METHOD of REDUCING and by DRO GENATING CHEMICA, COMPOUNDS by REACTING WITE: ALUMNUM-CONAN NG BYOFREDES Hermann E
    Patented Nov. 27, 1951 2,576,31 UNITED STATES PATENT OFFICE 2,56,31 METHOD OF REDUCING AND BY DRO GENATING CHEMICA, COMPOUNDS BY REACTING WITE: ALUMNUM-CONAN NG BYOFREDES Hermann E. Schlesirager and Albert E. Finholt, Chicago, Ill.; said Schlesinger assignor of one fourth to. Edaa, M. Schlesinger and said Fin holt assignor of one-fourth to Marion H. Finholt No Drawing. Application June 3, 1947, Serial No. 752,286 2 (Cairns. (C. 260-638) 2 This invention relates to methods of making LiAlH4. Although this new compound will be aluminum-containing hydrides and the reactions called lithium aluminum hydride in the present thereof, and also relates to products prepared by application, it may also be called lithium alumi said methods. nohydride or lithium tetrahydroaluminide. In This application is a continuation-in-part of one method of making lithium aluminum hydride, our copending application Serial No. 717,312, filed lithium hydride is reacted with an aluminum December 19, 1946, now Patent No. 2,567,972, halide such as aluminum chloride in the presence issued September 18, 1951. of a suitable liquid medium such as an ether. If We have discovered that these compounds, es the reagents are mixed in the proportions of the pecially the ether soluble lithium aluminum hy 0 following equation, or if an excess of lithium hy dride, are extremely useful chemical reagents. dride is used, the reaction proceeds as follows: - They may be employed for replacing halogens or Organic radicals by hydrogen in a great variety 4Li H--AlCl3->LiAlH4--3LiCl of compounds. As a result, their discovery has led to new methods, safer, more convenient, and 16 The liquid medium used is one in which one of more efficient than those hitherto known, for pro the reaction products, e.
    [Show full text]
  • MICROREVIEW Reactivity of Polar Organometallic Compounds In
    MICROREVIEW Reactivity of Polar Organometallic Compounds in Unconventional Reaction Media: Challenges and Opportunities Joaquin García-Álvarez,*[a] Eva Hevia,*[b] and Vito Capriati*[c] This paper is gratefully dedicated to the memory of Dr. Guy Lavigne Abstract: Developing new green solvents in designing chemical chemicals in chemical transformations is, indeed, solvents used products and processes or successfully employing the already as reaction media, which account for 80–90% of mass utilization existing ones is one of the key subjects in Green Chemistry and is in a typical pharmaceutical/fine chemical operational process. especially important in Organometallic Chemistry, which is an Thus, the solvent itself is often a critical parameter especially in interdisciplinary field. Can we advantageously use unconventional drug product manufacturing and is as well responsible for most reaction media in place of current harsh organic solvents also for waste generated in the chemical industries and laboratories.[3] polar organometallic compounds? This Microreview critically Following these considerations, some of the most critical analyses the state-of-the-art on this topic and showcases recent and intriguing questions that arise are: Can we get traditional developments and breakthroughs which are becoming new research organic solvents out of organometallic reactions?[4] Can we use directions in this field. Because metals cover a vast swath of the protic, recyclable, biodegradable, and cheap unconventional periodic table, the content is organised into three Sections solvents also for highly reactive organometallic compounds? discussing the reactivity of organometallic compounds of s-, p- and Answering these questions would not only mean to break new d-block elements in unconventional solvents.
    [Show full text]
  • The Synthesis and Thermochemistry of Organoboron and Phosphorus
    The Synthesis and Thermochemistry of Organoboron and Phosphorus Compounds A Thesis submitted by KHAWAJA SABIR HÜ3SAIR in candidature for the degree of Doctor of Philosophy of the University of London Royal Holloway College, Englefleld Green, Surrey. March, 1970. (U.K.;. CLASS N l / V u j AGO. No. I DA ft ACa â u L j j L À ProQuest Number: 10123886 All rights reserved INFORMATION TO ALL USERS The quality of this reproduction is dependent upon the quality of the copy submitted. In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if material had to be removed, a note will indicate the deletion. uest. ProQuest 10123886 Published by ProQuest LLC(2016). Copyright of the Dissertation is held by the Author. All rights reserved. This work is protected against unauthorized copying under Title 17, United States Code. Microform Edition © ProQuest LLC. ProQuest LLC 789 East Eisenhower Parkway P.O. Box 1346 Ann Arbor, Ml 48106-1346 "To all those who wished me to reach this stage" AOKNOlVLEDGmmTS The author wishes to express his gratitude to Dr# Arthur Finch for his Invaluable official supervision and encouragement. He Is highly thankful to Dr. P.J. Gardner for his entire supervision, unfailing encouragement and friendly advice. He Is also thankful to all the academic, technical and clerical staff, of the Chemistry Department, Royal Holloway College, for their co-operation and assistance. He wishes to thank the Petroleum Research Fund for a maintenance grant. ABSTRACT The synthesis and standard heats of formation of some substituted arylboroxlnes are reported.
    [Show full text]
  • The Response of Work Function of Thin Metal Films to Interaction with Hydrogen
    Vol. 114 (2008) ACTA PHYSICA POLONICA A Supplement Proceedings of the Professor Stefan Mr¶ozSymposium The Response of Work Function of Thin Metal Films to Interaction with Hydrogen R. Du¶s¤, E. Nowicka and R. Nowakowski Institute of Physical Chemistry, Polish Academy of Sciences Kasprzaka 44/52, 01-224 Warszawa, Poland The aim of this paper is to summarize the results of experiments carried out at our laboratory on the response of the work function of several thin ¯lms of transition metals and rare earth metals to interaction with molecular hydrogen. The main focus concerns the description of surface phenomena accompanying the reaction of hydride formation as a result of the adsor- bate's incorporation into the bulk of the thin ¯lms. Work function changes ¢© caused by adsorption and reaction concern the surface, hence this ex- perimental method is appropriate for solving the aforementioned problem. A di®erentiation is made between the work function changes ¢© due to cre- ation of speci¯c adsorption states characteristic of hydrides, and ¢© arising as a result of surface defects and protrusions induced in the course of the reaction. The topography of thin metal ¯lms and thin hydride ¯lms with defects and protrusions was illustrated by means of atomic force microscopy. For comparison, the paper discusses work function changes caused by H2 in- teraction with thin ¯lms of metals which do not form hydrides (for example platinum), or when this interaction is performed under conditions excluding hydride formation for thermodynamic reasons. Almost complete diminishing of ¢© was observed, in spite of signi¯cant hydrogen uptake on some rare earth metals, caused by formation of the ordered H{Y{H surface phase.
    [Show full text]
  • An X-Ray Study of Palladium Hydrides up to 100 Gpa: Synthesis and Isotopic Effects Bastien Guigue, Grégory Geneste, Brigitte Leridon, Paul Loubeyre
    An x-ray study of palladium hydrides up to 100 GPa: Synthesis and isotopic effects Bastien Guigue, Grégory Geneste, Brigitte Leridon, Paul Loubeyre To cite this version: Bastien Guigue, Grégory Geneste, Brigitte Leridon, Paul Loubeyre. An x-ray study of palladium hydrides up to 100 GPa: Synthesis and isotopic effects. Journal of Applied Physics, American Institute of Physics, 2020, 127 (7), pp.075901. 10.1063/1.5138697. hal-03024503 HAL Id: hal-03024503 https://hal.archives-ouvertes.fr/hal-03024503 Submitted on 11 Dec 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. An x-ray study of palladium hydrides up to 100 GPa: Synthesis and isotopic eects. Bastien Guigue,1, 2 Grégory Geneste,2 Brigitte Leridon,1 and Paul Loubeyre2, a) 1)LPEM, ESPCI Paris, PSL Research University, CNRS, Sorbonne Université, 75005 Paris, France 2)CEA, DAM, DIF, F-91297 Arpajon, France (Dated: 10 December 2020) The stable forms of palladium hydrides up to 100 GPa were investigated using the direct reaction of palladium with hydrogen (deuterium) in a laser-heated diamond anvil cell. The structure and volume of PdH(D)x were measured using synchrotron x-ray diffraction.
    [Show full text]
  • Hydrogen Storage Overview
    HYDROGEN STORAGE (Materials) Arturo Fernandez Madrigal Instituto de Energias Renovables-UNAM [email protected] Questions ¿what is the state of the art on hydrogen as energy storage? ¿Which are the main challenges of involved technologies? Hydrogen Economic Hydrogen and other fuels [Sørensen, 2005]. Propiedad Hidrógeno Metanol Metano Propano Gasolina Unidad Mínima energía de 0.02 ---- 0.29 0.25 0.24 mJ ignición Temperatura de 2045 ---- 1875 ---- 2200 °C flama Temperatura de 585 385 540 510 230-500 °C autoignición Máxima velocidad 3.46 ---- 0.43 0.47 ---- m/s de flama Rango de 4-75 7-36 5-15 2.5-9.3 1.0-7.6 Vol. % flamabildad Rango de 13-65 ---- 6.3-13.5 ---- 1.1-3.3 Vol. % explosividad Coeficiente de 0.61 0.16 0.20 0.10 0.05 10-3 m2/s difusión Energy Content of Comparative Fuels Physical storage of H2 •Compressed •Metal Hydride (“sponge”) •Cryogenically liquified •Carbon nanofibers Chemical storage of hydrogen •Sodium borohydride •Methanol •Ammonia •Alkali metal hydrides New emerging methods •Amminex tablets •Solar Zinc production •DADB (predicted) •Alkali metal hydride slurry Compressed •Volumetrically and Gravimetrically inefficient, but the technology is simple, so by far the most common in small to medium sized applications. •3500, 5000, 10,000 psi variants. Liquid (Cryogenic) •Compressed, chilled, filtered, condensed •Boils at 22K (-251 C). •Slow “waste” evaporation •Gravimetrically and volumetrically efficient •Kept at 1 atm or just slightly over. but very costly to compress 9 Metal Hydrides (sponge) •Sold by “Interpower” in Germany •Filled with “HYDRALLOY” E60/0 (TiFeH2) •Technically a chemical reaction, but acts like a physical storage method •Hydrogen is absorbed like in a sponge.
    [Show full text]