PDF Download

Total Page:16

File Type:pdf, Size:1020Kb

PDF Download SYNTHESIS0039-78811437-210X Georg Thieme Verlag Stuttgart · New York 2019, 51, 1115–1122 feature 1115 de Syn thesis S. Krieck et al. Feature Straightforward One-Pot Syntheses of Silylamides of Magnesium and Calcium via an In Situ Grignard Metalation Method Sven Krieck Philipp Schüler Jan M. Peschel Matthias Westerhausen* 0000-0002-1520-2401 Friedrich Schiller University Jena, Institute of Inorganic and Analytical Chemistry, Humboldtstraße 8, D-07743 Jena, Germany [email protected] Published as part of the 50 Years SYNTHESIS – Golden Anniversary Issue Received: 11.10.2018 metalation of (H)HMDS with calcium is very challenging Accepted after revision: 13.11.2018 and requires activation of the alkaline earth metal via metal Published online: 13.12.2018 DOI: 10.1055/s-0037-1610407; Art ID: ss-2018-z0683-fa vapor synthesis and co-condensation with the organic sol- 3 License terms: vent. Alternatively, ammonia-saturated solvents can be used for the direct metalation of (H)HMDS with calcium 9 Abstract Calcium bis[bis(trimethylsilyl)amide] (Ca(HMDS)2) is a widely turnings. These procedures are depicted in Scheme 1. used reagent in diverse stoichiometric and catalytic applications. These processes necessitate a straightforward and large-scale access of this Grignard reaction, complex. Calcium does not react with primary and secondary amines, Salt metathesis, Salt metathesis, Metalation Transmetalation but the addition of excess bromoethane to a mixture of calcium turn- M = Mg, R = aryl, alkyl M = Ca, M' = Sn, Hg ings and amines in THF at room temperature yields the corresponding M = Ca, R = aryl calcium bis(amides), calcium bromide and ethane. This in situ Grignard 2 M + 2 RX MX2 + 2 KR M'X2 + 2 KN(SiMe3) metalation method (iGMM) allows the preparation of calcium bis(am- – MX2 – 2 KX 1) – 2 KX ides) from secondary and primary trialkylsilyl-substituted amines and 2) distillation anilines on a multigram scale. R M M'{N(SiMe ) } 1 Background 2 3 2 2 2 The In Situ Grignard Metalation Method (iGMM) – 2 RH+ 2 HN(SiMe3)2 + M – M' 3 Properties of [(thf)2M(HMDS)2] 4 Applications and Perspective [(D)xM{N(SiMe3)2}2] Key words calcium amides, hexamethyldisilazides, silylamides, alka- 1) – 2 KX line earth metal amides, amidocalcium complexes 2) – KyCa{N(SiMe3)2}2+y extraction MX2 + 2 KN(SiMe3) 1 Background M = Mg, Ca; X = Br, I Salt metathesis The development of diverse procedures for the synthe- Scheme 1 Common established procedures for the synthesis of sis of calcium bis[bis(trimethylsilyl)amides] is based on the Mg(HMDS)2 and Ca(HMDS)2 involving several preparation and purifica- tion steps desperate need of soluble organocalcium complexes for var- ious applications. Therefore, different strategies were devel- oped independently at the beginning of the 1990s. The first All these procedures are related to severe drawbacks. syntheses of calcium bis[bis(trimethylsilyl)amide] Transmetalation protocols require the preparation, isola- (Ca(HMDS)2) were performed via transmetalation of tion and distillation of the precursor organometallics 1 2 Hg(HMDS)2 or Sn(HMDS)2, via metathetical approaches of (Hg(HMDS)2 or Sn(HMDS)2). Metathetical approaches ne- AHMDS (A = alkali metal) with calcium alkoxides3 or cessitate an exact stoichiometry to avoid formation of calci- – pseudohalides such as trifluoromethanesulfonates (tri- ates of the type [Ca(HMDS)3] (excess of AHMDS) and ha- flates)4 and arenesulfonates.5 The metathesis reaction of lide-containing product mixtures (substoichiometric 6,7 8 KHMDS with CaI2 in tetrahydrofuran and toluene yields AHMDS). The Ca(HMDS)2 product commonly contains at thf adducts and unsolvated Ca(HMDS)2, respectively. Direct least traces of potassium (potassium calciate formation Georg Thieme Verlag Stuttgart · New York — Synthesis 2019, 51, 1115–1122 1116 Syn thesis S. Krieck et al. Feature and/or traces of potassium iodide) that have to be removed Drawbacks of these procedures are obvious because anoth- by repeated recrystallization efforts. Prior to the direct er metalorganic precursor is required to prepare the meta- metalation of (H)HMDS the calcium metal has to be activat- lation reagent. ed to apply pyrophoric metal powders. In our hands, calci- The bis(trimethylsilyl)amido ligands guarantee not only um pieces are sluggish in reactions in ammonia-saturated solubility of the respective metal complexes in common or- solutions and dull, grayish reaction mixtures are obtained ganic solvents, but variations of this anion allow modifica- which prohibit the isolation of a pure product. These initial tion of the electronic and (especially) steric properties. investigations are summarized and evaluated in more detail Transmetalation of Sn[N(SiMe2CH2)2]2 with calcium in THF elsewhere.10 yields the corresponding tris(thf) adduct of calcium Due to these reasons, diverse strategies have been de- bis(2,2,5,5-tetramethyl-1-aza-2,5-disilylcyclopentanide).15 veloped to accelerate the synthesis of highly pure In contrast, enlargement of the amido ligand and the use of Ca(HMDS)2. The reaction of calcium with (H)HMDS in THF Sn[N(SiMe3)Si(SiMe3)3]2 in the transmetalation procedure can be ensured via addition of BiPh3 under ultrasonica- only gives the aminyl radicals and finally the amine 11 tion. The organometallic metalation of (H)HMDS with HN(SiMe3)Si(SiMe3)3, but a calcium bis(amide) cannot be dibenzylcalcium12 circumvents the necessity of metal acti- isolated. Suitable procedures for the preparation of vation prior to use. Arylcalcium reagents (heavy Grignard Ca[N(SiHMe2)2]2 are the metathetical approach with 13 reagents) are easily available and represent suitable meta- KN(SiHMe2)2 and CaI2 as well as the transamination of 14 16 lation reagents for the syntheses of calcium amides. Ca(HMDS)2 with HN(SiHMe2)2. The metathesis reaction of the potassium amides with calcium iodide offers access to solvated bulky calcium bis(amides) with amido ligands like Biographical Sketches Sven Krieck (left) studied chemistry at Frie- Philipp Schüler (second from left) studied ny, and studied for his Ph.D. thesis at the drich Schiller University Jena, Germany, and the synthesis and coordination chemistry of University of Stuttgart, Germany, under the graduated in 2007 with his diploma thesis in alkaline earth metal bis[bis(trimethylsi- supervision of Professor Gerd Becker. In the field of electrochemical studies on het- lyl)amides] at Friedrich Schiller University Je- 1987/88, he worked as a postdoctoral fellow erosupramolecular aggregates in the group na, Germany, and obtained his M.Sc. degree with Professor Robert T. Paine at the Univer- of Professor Günter Kreisel. He then joined in 2018. He is currently a Ph.D. student in sity of New Mexico in Albuquerque, USA, in the group of Professor Matthias Westerhau- the Westerhausen group at the same institu- the field of phosphanylboranes. Back at the sen and completed his Ph.D. in April 2010 tion. University of Stuttgart, he finished his habili- working on the stabilization of organocalci- tation in the Institute of Inorganic Chemistry um compounds. His thesis was awarded with Jan M. Peschel (second from right) studied in December 1994 and received the venia the university prize as best thesis in 2010. chemistry at Friedrich Schiller University Je- legendi for Inorganic Chemistry in February After a postdoctoral fellowship with Profes- na, Germany, and obtained his B.Sc. degree 1995. From 1996 to 2004 he was a professor sor Nadia Mösch-Zanetti at Karl Franzens in 2017. During his laboratory courses he in- at Ludwig Maximilians University Munich University in Graz, Austria, he returned to vestigated the synthesis and coordination where he was also vice rector from 2001 to the Westerhausen group in 2011. Today he chemistry of alkaline earth metal 2004. He was awarded the Teaching Excel- is lecturer at the Institute of Inorganic and bis[bis(trimethylsilyl)amides]. lence Award of the State of Bavaria in 1998. Analytical Chemistry at Friedrich Schiller Uni- Since 2004, he has been teaching and re- Matthias Westerhausen (right) obtained versity Jena, Germany. searching at Friedrich Schiller University Je- his diploma degree in chemistry in 1983 na, Germany. from Philipps University in Marburg, Germa- Georg Thieme Verlag Stuttgart · New York — Synthesis 2019, 51, 1115–1122 1117 Syn thesis S. Krieck et al. Feature N(SiMe3)(SiMe2tBu), N(SiMe3)(SiPh2tBu), and havior of aromatic and aliphatic hydrocarbyl iodides and 17 N(SiMe3)(SiPh3). The salt metathesis reaction even allows bromides R–X (X = Br, I) lies in the nature of the hydrocarbyl the synthesis of unsolvated calcium bis[bis(triisopropylsi- halide radical anions after the first electron transfer from lyl)amide] with a nearly linear N–Ca–N fragment of the metal onto R–X. Without stabilization of the negative 172.62(11)°.18 This metathetical approach also provides ac- charge (via delocalization into the aryl group or via negative cess to substituted N-trimethylsilylanilides with bulky aryl hyperconjugation to the trimethylsilyl groups) the C–X groups like 2,4,6-trimethylphenyl (mesityl, Mes)19 and 2,6- bond is elongated much more, easing dissociation into the diisopropylphenyl (Dipp).20 halide anion and the alkyl radical. Furthermore, the co-ligands of Ca(HMDS)2 can be varied Calcium is unable to directly metalate (H)HMDS in com- to also influence the shielding of the reactive Ca–N bonds. mon organic solvents (aliphatic and aromatic hydrocar- Structural studies have been reported for dimeric bons, ethers) regardless of a prior activation procedure. 21 [Ca(HMDS)2]2 as well as for the ether solvates Therefore, commercially available calcium granules and this 21 22 [(dme)Ca(HMDS)2], [(thf)2Ca(HMDS)2], and amine were placed together in a Schlenk flask in THF. Next, 23 [(thp)2Ca(HMDS)2]. Electroneutral co-ligands with nitro- ethyl bromide, dissolved in THF, was added dropwise at gen donor atoms like tmeda24 and imidazole25 form stable room temperature and the reaction mixture was stirred for complexes too.
Recommended publications
  • Download Article
    Volume 10, Issue 3, 2020, 5412 - 5417 ISSN 2069-5837 Biointerface Research in Applied Chemistry www.BiointerfaceResearch.com https://doi.org/10.33263/BRIAC103.412417 Original Research Article Open Access Journal Received: 26.01.2020 / Revised: 02.03.2020 / Accepted: 03.03.2020 / Published on-line: 09.03.2020 Obtaining salts of resin acids from Cuban pine by metathesis reactions Olinka Tiomno-Tiomnova 1 , Jorge Enrique Rodriguez-Chanfrau 2 , Daylin Gamiotea-Turro 2 , Thayná Souza Silva 3 , Carlos Henrique Gomes Martins 3 , Alexander Valerino-Diaz 2 , Yaymarilis Veranes-Pantoja 4 , Angel Seijo-Santos 1 , Antonio Carlos Guastaldi 2 1Center of Engineering and Chemical Investigations. Havana. CP 10600, Cuba 2Group of Biomaterials, Department of Physical Chemistry, Institute of Chemistry, Sao ~ Paulo State University (UNESP), Araraquara, SP, 14800-060, Brazil 3Laboratory of Research on Antimicrobial Trials (LaPEA), Institute of Biomedical Sciences – ICBIM, Federal University of Uberlândia, Uberlândia, Brazil 4Biomaterials Center. University of Havana. Havana. CP 10600, Cuba *corresponding author e-mail address: [email protected] | Scopus ID 7801488065 ABSTRACT The resin acids obtained from the Cuban pine rosin are the starting material for the development and application of metathesis reactions. These reactions allow the obtaining of salts with high added value which could be used in the development of biomaterials for dental use. The objective of this work was to obtain calcium, magnesium and zinc resinates from the resin acid obtained from the Cuban pine resin by metathesis reaction for possible use in the development of biomaterials. The products obtained were evaluated by elemental analysis, X-ray powder diffraction, infrared spectroscopy, scanning electron microscopy associated with electron dispersion spectroscopy, nuclear magnetic resonance and biological tests (antibacterial activity).
    [Show full text]
  • A Metal-Free Approach to Biaryl Compounds: Carbon-Carbon Bond Formation from Diaryliodonium Salts and Aryl Triolborates
    Portland State University PDXScholar Dissertations and Theses Dissertations and Theses Winter 4-3-2015 A Metal-Free Approach to Biaryl Compounds: Carbon-Carbon Bond Formation from Diaryliodonium Salts and Aryl Triolborates Kuruppu Lilanthi Jayatissa Portland State University Follow this and additional works at: https://pdxscholar.library.pdx.edu/open_access_etds Part of the Catalysis and Reaction Engineering Commons Let us know how access to this document benefits ou.y Recommended Citation Jayatissa, Kuruppu Lilanthi, "A Metal-Free Approach to Biaryl Compounds: Carbon-Carbon Bond Formation from Diaryliodonium Salts and Aryl Triolborates" (2015). Dissertations and Theses. Paper 2229. https://doi.org/10.15760/etd.2226 This Thesis is brought to you for free and open access. It has been accepted for inclusion in Dissertations and Theses by an authorized administrator of PDXScholar. Please contact us if we can make this document more accessible: [email protected]. A Metal-Free Approach to Biaryl Compounds: Carbon-Carbon Bond Formation from Diaryliodonium Salts and Aryl Triolborates. by Kuruppu Lilanthi Jayatissa A thesis submitted in partial fulfillment of the requirement for the degree of Master of Science in Chemistry Thesis Committee: David Stuart, Chair Robert Strongin Theresa McCormick Portland State University 2015 Abstract Biaryl moieties are important structural motifs in many industries, including pharmaceutical, agrochemical, energy and technology. The development of novel and efficient methods to synthesize these carbon-carbon bonds is at the forefront of synthetic methodology. Since Ullmann’s first report of stoichiometric Cu-mediated homo-coupling of aryl halides, there has been a dramatic evolution in transition metal catalyzed biaryl cross-coupling reactions.
    [Show full text]
  • THAT ARE NOT ALLOLLIKULTTUUS009958363B2 (12 ) United States Patent ( 10 ) Patent No
    THAT ARE NOT ALLOLLIKULTTUUS009958363B2 (12 ) United States Patent ( 10 ) Patent No. : US 9 , 958 ,363 B2 Smart et al. (45 ) Date of Patent: May 1 , 2018 ( 54 ) FLUOROUS AFFINITY EXTRACTION FOR (56 ) References Cited IONIC LIQUID - BASED SAMPLE PREPARATION U . S . PATENT DOCUMENTS 7 ,273 ,587 B1 9 / 2007 Birkner et al . ( 71 ) Applicant: Agilent Technologies , Inc. , Loveland , 7 ,273 ,720 B1 9 / 2007 Birkner et al. CA (US ) ( Continued ) ( 72 ) Inventors: Brian Phillip Smart, San Jose , CA (US ) ; Brooks Bond - Watts , Fremont, FOREIGN PATENT DOCUMENTS CA (US ) ; James Alexander Apffel, Jr ., WO WO2007110637 10 /2007 Mountain View , CA (US ) WO WO2011155829 12 / 2011 ( 73 ) Assignee : Agilent Technologies , Inc ., Santa Clara , OTHER PUBLICATIONS CA (US ) Yuesheng Ye , Yossef A . Elabd “ Anion exchanged polymerized ionic ( * ) Notice : Subject to any disclaimer, the term of this liquids: High free volume single ion conductors ” Polymer 52 ( 2011 ) patent is extended or adjusted under 35 1309 - 1317 , plus supplementary data ( pp . 1 - 6 ) . * U . S . C . 154 (b ) by 168 days . (Continued ) ( 21) Appl . No. : 14 /724 ,656 Primary Examiner — Christine T Mui ão( 22 ) Filed : May 28 , 2015 Assistant Examiner - Emily R . Berkeley (6565 ) Prior Publication Data (57 ) ABSTRACT US 2015 /0369711 A1 Dec . 24 , 2015 A method for removing an ionic liquid from an aqueous Related U . S . Application Data sample is provided . In some embodiments , the method includes : ( a ) combining an aqueous sample including an ( 60 ) Provisional application No . 62/ 016 ,000 , filed on Jun . ionic liquid with an ion exchanger composition including an 23 , 2014 , provisional application No . 62 /016 , 003 , ion exchanger counterion to produce a solution including a (Continued ) fluorous salt of the ionic liquid , where at least one of the ionic liquid and the ion exchanger counterion is fluorinated ; (51 ) Int .
    [Show full text]
  • 1 Structural Characterization of a Tetrametallic Diamine-Bis(Phenolate) Complex of Lithium and Synthesis of a Related Bismuth Co
    Structural Characterization of a Tetrametallic Diamine-bis(phenolate) Complex of Lithium and Synthesis of a Related Bismuth Complex Marcus W. Drover,a Jennifer N. Murphy,a Jenna C. Flogeras,a Céline M. Schneider,a,b Louise N. Dawe,a,c and Francesca M. Kerton*a a Department of Chemistry, Memorial University of Newfoundland St. John’s, Newfoundland, Canada A1B 3X7 b NMR Laboratory, C-CART, Memorial University of Newfoundland, St. John’s, NL, A1B 3X7, Canada c C-CART X-ray Diffraction Laboratory, Memorial University of Newfoundland, St. John’s, Newfoundland, Canada A1B 3X7; Current address, Department of Chemistry, Wilfrid Laurier University, Science Building, 75 University Ave. W., Waterloo, Ontario, Canada N2L 3C5 * Author to whom correspondence should be addressed. Tel: +1-709-864-8089, Fax: +1-709- 864-3702, E-mail: [email protected] Contribution For Special Issue on “Modern Canadian Inorganic Chemistry” Abstract A novel lithium complex was prepared from the reaction of 1,4-bis(2-hydroxy-3,5-di-tert-butyl- BuBuIm benzyl)imidazolidine H2[O2N2] (L1H2) with n-butyllithium to provide the corresponding 7 tetralithium amine-bis(phenolate) complex {Li2[L1]}2•4THF, 1. Variable temperature Li NMR revealed that this complex is labile in solution, dissociating at elevated temperatures to afford two dilithium entities. Additionally, 7Li MAS NMR was performed on 1 to provide information regarding the lithium coordination environment in the bulk solid-state. The reactivity of 1 was assessed in the ring-expansion polymerization of ε-caprolactone (ε-CL), which was first order in ε-CL with an activation energy of 50.9 kJmol-1.
    [Show full text]
  • Syntheses and Studies of Group 6 Terminal Pnictides, Early-Metal Trimetaphosphate Complexes, and a New Bis-Enamide Ligand
    Syntheses and Studies of Group 6 Terminal Pnictides, Early-Metal Trimetaphosphate Complexes, and a New bis-Enamide Ligand by MASSACHUSMS INSTITUTE Christopher Robert Clough OF TECHNOLOGY B.S., Chemistry (2002) JUN 072011 M.S., Chemistry (2002) The University of Chicago Submitted to the Department of Chemistry ARCHIVES in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the MASSACHUSETTS INSTITUTE OF TECHNOLOGY June 2011 @ Massachusetts Institute of Technology 2011. All rights reserved. Author.. .. .. .. .. ... .. .. .. .. .... Department of Chemistry May 6,2011 Certified by............. Christopher C. Cummins Professor of Chemistry Thesis Supervisor Accepted by ........ Robert W. Field Chairman, Department Committee on Graduate Studies 2 This Doctoral Thesis has been examined by a Committee of the Department of Chemistry as follows: Professor Daniel G. Nocera ..................... Henry Dreyfus Profe~ssofof Energy and Pr6fessor of Chemistry Chairman Professor Christopher C. Cummins............................ .................. Professor of Chemistry Thesis Supervisor Professor Richard R. Schrock .................. Frederick G. Keyes Professor of Chemistry Committee Member 4 For my Grandfather: For always encouraging me to do my best and to think critically about the world around me. 6 Alright team, it's the fourth quarter. The Lord gave us the atoms and it's up to us to make 'em dance. -Homer Simpson 8 Syntheses and Studies of Group 6 Terminal Pnictides, Early-Metal Trimetaphosphate Complexes, and a New bis-Enamide Ligand by Christopher Robert Clough Submitted to the Department of Chemistry on May 6, 2011, in partial fulfillment of the requirements for the degree of Doctor of Philosophy Abstract Investigated herein is the reactivity of the terminal-nitrido, trisanilide tungsten complex, NW(N[i- Pr]Ar) 3 (Ar = 3,5-Me 2C6H3, 1).
    [Show full text]
  • Ir(COD)Cl Com- Plexes
    In depth study on chloride abstractions from (NHC)Ir(COD)Cl com- plexes Gellért Sipos†, Pengchao Gao†, Daven Foster†, Brian W. Skelton‡, Alexandre N. Sobolev‡, and Reto Dorta†* † School of Chemistry and Biochemistry, University of Western Australia, M310, 35 Stirling Highway, 6009 Perth, WA, Australia ‡ Centre for Microscopy, Characterisation and Analysis, University of Western Australia, 35 Stirling Highway, 6009 Perth, WA, Australia Supporting Information Placeholder ABSTRACT: While attempting to prepare a series of cationic NHC-Ir complexes of general formula [(NHC)Ir(COD)]+ via the silver salt metathesis reaction of its precursor (NHC)Ir(COD)Cl in dichloromethane, we unexpectedly synthesized [(µ-Cl)-{(2,7- SICyNap)Ir(COD)}·{Ag(OTf)}], a chloride-bridged Ir-Ag adduct. This result led us to investigate the chloride abstraction from the (NHC)Ir(COD)Cl system in detail. We show how the outcome of this ubiquitous reaction is dependent on a fine balance between nucleophilicity of the weakly coordinating anion (WCA) and the polarity / coordinating ability of the reaction medium. A frequent- ly encountered alternative to using silver salts is also presented and compared. The experimental difference in the reactivities of cationic catalysts in a representative intramolecular hydroamination reaction shows how cationic Ir-Ag adduct can fail to deliver the reaction product through what appears to be a stabilization of the catalytically inactive iridium-silver intermediate by the educt. 1. INTRODUCTION halide), which is replaced by a weakly coordinating
    [Show full text]
  • Synthesis and Characterization of Molybdenum N-Heterocyclic Phosphenium
    Synthesis and Characterization of Molybdenum N-Heterocyclic Phosphenium and Phosphido Complexes Undergraduate Research Thesis Presented in partial fulfillment of the requirements for graduation with honors research distinction in Chemistry in the undergraduate colleges of The Ohio State University by Riley Kelch The Ohio State University April 2021 Project Advisor: Professor Christine M. Thomas, Department of Chemistry and Biochemistry Acknowledgements I would like to express my sincerest gratitude to my advisor Professor Christine Thomas. Her guidance has been crucial to the advancement of this project and to my development as a scientist, thinker, and all-around person. Additionally, I must thank my long-time graduate student mentor, Andy Poitras. He taught me how to function in a glovebox, guided me through science before I knew anything about (in)organic chemistry, and took an egregious number of NMRs for me, amongst other things. I also want to thank Greg Hatzis and Leah Oliemuller for being great mates on the NHP project in Michael Scott as well as TJ Yokley and Josh Shoopman for thoughtful discussions and for working night shifts with me through the Covid-19 pandemic. I’ll end with a list of everyone I’ve worked with in the Thomas lab, as I’m grateful to all of you. Prof. Christine Thomas Dr. Jeffrey Beattie Josh Shoopman Dr. Elizabeth Lane Subha Himel Dr. Kyounghoon Lee Nathan McCutcheon Dr. TJ Yokley Jeremiah Stevens Dr. Katie Gramigna Sean Morrison Dr. Hongtu Zhang David Ullery Dr. Andrew Poitras Shannon Cooney Greg Hatzis Nathan Pimental Leah Oliemuller Canning Wang Nate Hunter Prof. Ewan Hamilton Brett Barden Dr.
    [Show full text]
  • Mechanochemical Synthesis of Hydrogen-Storage Materials Based on Aluminum, Magnesium and Their Compounds Ihor Z
    Iowa State University Capstones, Theses and Graduate Theses and Dissertations Dissertations 2015 Mechanochemical synthesis of hydrogen-storage materials based on aluminum, magnesium and their compounds Ihor Z. Hlova Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/etd Part of the Materials Science and Engineering Commons, Mechanics of Materials Commons, and the Oil, Gas, and Energy Commons Recommended Citation Hlova, Ihor Z., "Mechanochemical synthesis of hydrogen-storage materials based on aluminum, magnesium and their compounds" (2015). Graduate Theses and Dissertations. 14573. https://lib.dr.iastate.edu/etd/14573 This Dissertation is brought to you for free and open access by the Iowa State University Capstones, Theses and Dissertations at Iowa State University Digital Repository. It has been accepted for inclusion in Graduate Theses and Dissertations by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. Mechanochemical synthesis of hydrogen-storage materials based on aluminum, magnesium and their compounds by Ihor Z. Hlova A dissertation submitted to the graduate faculty in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Major: Materials Science and Engineering Program of Study committee: Vitalij K. Pecharsky, Major Professor Karl A. Gschneidner, Jr. Marek Pruski Duane Johnson Scott Chumbley Iowa State University Ames, Iowa 2015 Copyright © Ihor Z. Hlova, 2015. All rights reserved. ii
    [Show full text]
  • Recent Advances of Imidazolin-2-Iminato in Transition Metal Chemistry Preethi Raja1, Shanmugam Revathi1 and Tapas Ghatak1,* Abstract
    Eng. Sci., 2020, 12, 23–37 Engineered Science DOI: https://dx.doi.org/10.30919/es8d1151 Recent Advances of Imidazolin-2-iminato in Transition Metal Chemistry Preethi Raja1, Shanmugam Revathi1 and Tapas Ghatak1,* Abstract A new class of monoanionic nitrogen donor ligands imidazolin-2-iminato (ImRN‒) is produced from the reactivity of N- heterocyclic carbenes (NHCs) towards organic azides and is isolobally related to imido ligands (RN2‒). The imidazolin-2-iminato ligands essentially can be derived by substituting alkyl or aryl group from imido moieties. The proton abstraction from imidazolin-2-imine results in the monoanionic imidazolin-2-iminato ligands that possesses the exocyclic nitrogen, which strongly favors the binding with electrophiles. The nucleophilicity of anionic nitrogen is markedly increased by the charge (positive) delocalization into the five-membered heterocyclic ring. Altering the N-substitutions could meet the necessities for kinetic stabilization of high valent reactive species. These ligands have been slowly cemented the status as a potential alternative for ubiquitous cyclopentadienyl ligand and continued receiving attention. These ligands have progressively accustomed as the ancillary ligands for early transition metals, rare earth elements, or early actinides affording pincer complexes or "pogo stick" type compounds. In this article, the present chemistry of transition metal elements bearing imidazolin-2-iminato/imine ligands is reviewed from the year 2015 to date. Keywords: N-heterocyclic carbene; Catalysis; Polymerization;
    [Show full text]
  • Handout Module 3 Chapter 1 Class X
    No. of printed pages-5 ATOMIC ENERGY CENTRAL SCHOOL- KUDANKULAM Handout –Module-3/4 Subject-Chemistry Class-X Lesson No.- Chapter 1- Chemical Reactions and Equations Name of the topic – Displacement, Double Displacement, Neutralisation Reaction Displacement Reaction A single-displacement reaction is a chemical reaction in which one (or more) element(s) replaces an/other element(s) in a compound. It can be represented generically as: A + B-C → A-C + B Displacement reaction can also be defined as – “More reactive metal displaces less reactive metal from its salt solution.” Examples- Fe + CuSO 4(aq) FeSO 4(aq) +Cu 2AgNO 3 +Cu Cu(NO 3)2 + 2Ag Zn + HCl ZnCl 2 + H 2 Characteristics of Displacement reaction High reactive metal displaces low reactive metal. The displacement process is slow. In this type of reaction metal displaces other metal from its salt solution. Zn(s) + CuSO 4(aq) → ZnSO4(aq) + Cu(s) (Copper sulphate) (Zinc sulphate) Pb(s) + CuCl 2(aq) → PbCl 2(aq) + Cu(s) (Copper chloride) (Lead chloride) Zinc and lead are more reactive elements than copper. They displace copper from its compounds. Activity 1.9 NCERT TEXT Experiment -Take three iron nails and clean them by rubbing with sand paper.Take two test tubes marked as (A) and (B). In each test tube, take about 10 ml copper sulphate solution.Tie two iron nails with a thread and immerse them carefully in the copper sulphate solution in test tube B for about 20 minutes. Keep one iron nail aside for comparison. After 20 minutes, take out the iron nails from the copper sulphate solution.
    [Show full text]
  • Isonitrile Ruthenium and Iron PNP Complexes: Synthesis, Characterization and Catalytic Assessment for Base-Free Dehy- Drogenative Coupling of Alcohols
    Isonitrile ruthenium and iron PNP complexes: Synthesis, characterization and catalytic assessment for base-free dehy- drogenative coupling of alcohols. Duc Hanh Nguyen,a Delphine Merel,a Nicolas Merle,a Xavier Trivelli,b Frédéric Capeta and Régis M. Gauvin*,c. a Univ. Lille, CNRS, Centrale Lille, ENSCL, Univ. Artois, UMR 8181 - UCCS - Unité de Catalyse et Chimie du Solide, F- 59000 Lille, France b Université de Lille, CNRS, INRA, Centrale Lille Institute, Univ. Artois, FR 2638 - IMEC - Institut Michel-Eugène Che- vreul, F-59000 Lille, France c Chimie ParisTech, PSL University, CNRS, Institut de Recherche de Chimie Paris, 75005 Paris, France. E-mail : [email protected] KEYWORDS. Dehydrogenation • ruthenium • iron • pincer ligands • isonitrile. Supporting Information Placeholder H H ABSTRACT: Neutral and ionic ruthenium and iron aliphatic PNP -type pincer complexes (PNP = NH(CH2CH2PiPr2)2) bearing benzyl, n- H butyl or tert-butyl isocyanide ancillary ligands have been prepared and characterized. Reaction of [RuCl2(PNP )]2 with one equivalent CN- H R per ruthenium center affords complexes [Ru(PNP )Cl2(CNR)] (R= benzyl, 1a, R= n-butyl, 1b, R= t-butyl, 1c), with cationic H H [Ru(PNP )(Cl)(CNR)2]Cl 2a-c as side-products. Complexes 2a-c are selectively prepared upon reaction of [RuCl2(PNP )]2 with 2 equiva- H lents of isonitrile per ruthenium center. Dichloride species 1a-c react with excess NaBH4 to afford [Ru(PNP )(H)(BH4)(CN-R)] 3a-c, ana- logues to benchmark Takasago catalyst [Ru(PNP)(H)(BH4)(CO)]. Reaction of 1a-c with a single equivalent of NaBH4 under protic conditions results in formation of hydrido chloride derivatives [Ru(PNPH)(H)(Cl)(CN-R)] (4a-c), from which 3a-c can be prepared upon reaction with H excess NaBH4.
    [Show full text]
  • Synthesis and Reactivity of Group 12 Β-Diketiminate Coordination Complexes
    Synthesis and Reactivity of Group 12 β-Diketiminate Coordination Complexes By Dylan Webb A thesis Submitted to Victoria University of Wellington in fulfilment of the requirements for the degree of Masters of Science In Chemistry Victoria University of Wellington 2016 Abstract The variable β-diketiminate ligand poses as a suitable chemical environment to explore unknown reactivity and functionality of metal centres. Variants on the β-diketiminate ligand can provide appropriate steric and electronic stabilization to synthesize a range of β-diketiminate group 12 metal complexes. This project aimed to explore various β-diketiminate ligands as appropriate ancillary ligands to derivatise group 12 element complexes and investigate their reactivity. i A β-diketiminato-mercury(II) chloride, [o-C6H4{C(CH3)=N-2,6- Pr2C6H3}{NH(2,6- i i Pr2C6H3)}]HgCl, was synthesized by addition of [o-C6H4{C(CH3)=N-2,6- Pr2C6H3}{NH(2,6- i Pr2C6H3)}]Li to mercury dichloride. Attempts to derivatise the β-diketiminato-mercury(II) chloride using salt metathesis reactions were unsuccessful with only β-diketiminate ligand degradation products being observed in the 1H NMR. i A β-diketiminato-cadmium chloride, [CH{(CH3)CN-2,6- Pr2C6H3}2]CdCl, was derivatized to a i β-diketiminato-cadmium phosphanide, [CH{(CH3)CN-2,6- Pr2C6H3}2]Cd P(C6H11)2, via a lithium dicyclohexyl phosphanide and a novel β-diketiminato-cadmium hydride, [CH{(CH3)CN-2,6- i Pr2C6H3}2]CdH, via Super Hydride. Initial reactivity studies of the novel cadmium hydride with various carbodiimides yielded a β-diketiminato-homonuclear cadmium-cadmium i dimer, [CH{(CH3)CN-2,6- Pr2C6H3}2Cd]2, which formed via catalytic reduction of the cadmium hydride.
    [Show full text]