Summaries of FY 1996 Research in the Chemical Sciences
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Xerox University Microfilms, Ann Arbor, M Ichigan 48106
I I I 77-2394 EDWARDS, Robert Charles, 1949- SYNTHESES AND CHARACTERIZATION OF CHROMIUM COMPLEXES WITH TETRAAZA MACROCYCLIC LIGANDS. The Ohio State University, Ph.D., 1976 Chemistry, inorganic Xerox University Microfilms, Ann Arbor, Michigan 48106 SYNTHESES AND CHARACTERIZATION OF CHROMIUM COMPLEXES WITH TETRAAZA MACROCYCLIC LIGANDS DISSERTATION Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University By Robert Charles Edwards, B.S. The Ohio State University 1976 Reading Committee: Approved by Professor Daryle H. Busch Professor Devon W. Meek Professor Eugene P. Schram Advised Department of Chemistry To Debra and Marie & # 5J: aj: % # # # ACKNOWLEDGEMENTS I would like to acknowledge the help given to me by fellow graduate students, post-doctoral fellows in Dr. Busch's group, and the staff in the Department of Chemistry. I want to especially thank Professor Daryle H„ Busch for his guidance and understanding,, iii CURRICULUM VITAE March 2, 1949. ................ ... ..................................................... Born, Marion, Ohio 1971 .................................................. ................................................ B .S., Heidelberg College Tiffin, Ohio 1971-1974. ....................................................................................... Teaching Associate, Dept, of Chemistry, The Ohio State University, Columbus, Ohio 1974-197 5 ................................................................................. Allied-Chemical -
An Empirical Formula Expressing the Mutual Dependence of C-C Bond Distances* Arpad Furka Department of Organic Chemistry Eotvos Lorcind University, Muzeum Krt
CROATICA CHEMICA ACTA CCACAA 56 (2) 191-197 (1983) YU ISSN 0011-1643 CCA-1368 UDC 547 :541.6 Originai Scientific Paper An Empirical Formula Expressing the Mutual Dependence of C-C Bond Distances* Arpad Furka Department of Organic Chemistry Eotvos Lorcind University, Muzeum krt. 4/B Budapest, 1088, Hungary Received August 30, 1982 An empirical formula is suggested to describe the mutuaJ dependence of the length of the bonds formed by a central atom in systems built up from equivalent carbon atoms, e.g. diamond, graphite, the cumulene and polyyne chains and intermediate struc tures between them. A geometrical representation of the relation ship is a regular tetrahedron. A point of this tetrahedron charac terizes the arrangement of the atoms around the central one. From the position of the point the bond distances - and possibly the bond angles - can be deduced. Experimental bond length determinations have made clear in the last few decades that the C-C bond distances vary over a relatively long range, from about 1.2 A to about 1.6 A. There were several attempts to correlate these bond distances on empirical way to different factors like double-bond 1 2 4 character, • n:-bond order,3 state of hybridization, •5 the number of adjacent bonds,6 or the overlap integrals.7 Recently ·a new empirical formula has been suggested to describe the mutual dependence of the C-C bond distances.8 The subject of this paper is the interpretation of this empirical equation. Carbon has three allotropic modifications: diamond, graphite and the not completely characterized chain form9•10 (carbynes). -
© Copyright 2013 Jennifer L. Steele
© Copyright 2013 Jennifer L. Steele DIVALENT TRANSITION METAL CENTERS: THE SYNTHESIS OF NEW CHEMICAL VAPOR DEPOSITION PRECURSORS AND STUDIES OF ETHYLENE POLYMERIZATION AND OLIGOMERIZATION CATALYSTS BY JENNIFER L. STEELE DISSERTATION Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Chemistry in the Graduate College of the University of Illinois at Urbana-Champaign, 2013 Urbana, Illinois Doctoral Committee: Professor Gregory S. Girolami, Chair Assistant Professor Alison R. Fout Professor John A. Katzenellenbogen Professor Thomas B. Rauchfuss Abstract Volatile transition metal complexes that contain boron hydride ligands are desirable for their potential as precursors for metal diboride films for microelectronics applications. Recently our group has discovered a new class of potential precursors in the metal complexes of the chelating borohydride, N,N-dimethylaminodiboranate (DMADB). To date, attempts to synthesize homoleptic complexes of the late transition metals have afforded intractable mixtures, likely the result of overreduction of the metal center. This work has focused on the synthesis and characterization of heteroleptic complexes of the late transition metals that contain both DMADB and 1,2,3,4,5,-pentamethylcyclopentadienyl ligands. The reaction of metal complexes of the form [Cp*MX]n, where Cp* is 1,2,3,4,5,- pentamethylcyclopentadienyl, M = Cr, Fe, Co, or Ru, and X = Cl or I with sodium dimethylaminodiboranate (NaDMADB) in diethyl ether affords the divalent complexes [Cp*M(DMADB)]. Additionally, the analogous vanadium compound [Cp*V(DMADB)] can be synthesized from the reduction of [Cp*VCl2]3 with NaDMADB in diethyl ether. All of these compounds are volatile under static vacuum at room temperature, but are also thermally sensitive; the iron and ruthenium derivatives decompose at room temperature over a day. -
Conversion of Methoxy and Hydroxyl Functionalities of Phenolic Monomers Over Zeolites Rajeeva Thilakaratne Iowa State University
Chemical and Biological Engineering Publications Chemical and Biological Engineering 2016 Conversion of methoxy and hydroxyl functionalities of phenolic monomers over zeolites Rajeeva Thilakaratne Iowa State University Jean-Philippe Tessonnier Iowa State University, [email protected] Robert C. Brown Iowa State University, [email protected] Follow this and additional works at: https://lib.dr.iastate.edu/cbe_pubs Part of the Biomechanical Engineering Commons, and the Catalysis and Reaction Engineering Commons The ompc lete bibliographic information for this item can be found at https://lib.dr.iastate.edu/ cbe_pubs/328. For information on how to cite this item, please visit http://lib.dr.iastate.edu/ howtocite.html. This Article is brought to you for free and open access by the Chemical and Biological Engineering at Iowa State University Digital Repository. It has been accepted for inclusion in Chemical and Biological Engineering Publications by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. Conversion of methoxy and hydroxyl functionalities of phenolic monomers over zeolites Abstract This study investigates the mechanisms of gas phase anisole and phenol conversion over zeolite catalyst. These monomers contain methoxy and hydroxyl groups, the predominant functionalities of the phenolic products of lignin pyrolysis. The proposed reaction mechanisms for anisole and phenol are distinct, with significant differences in product distributions. The nia sole mechanism involves methenium ions in the conversion of phenol and alkylating aromatics inside zeolite pores. Phenol converts primarily to benzene and naphthalene via a ring opening reaction promoted by hydroxyl radicals. The hep nol mechanism sheds insights on how reactive bi-radicals generated from fragmented phenol aromatic rings (identified as dominant coke precursors) cyclize rapidly to produce polyaromatic hydrocarbons (PAHs). -
Stabilization of Anti-Aromatic and Strained Five-Membered Rings with A
ARTICLES PUBLISHED ONLINE: 23 JUNE 2013 | DOI: 10.1038/NCHEM.1690 Stabilization of anti-aromatic and strained five-membered rings with a transition metal Congqing Zhu1, Shunhua Li1,MingLuo1, Xiaoxi Zhou1, Yufen Niu1, Minglian Lin2, Jun Zhu1,2*, Zexing Cao1,2,XinLu1,2, Tingbin Wen1, Zhaoxiong Xie1,Paulv.R.Schleyer3 and Haiping Xia1* Anti-aromatic compounds, as well as small cyclic alkynes or carbynes, are particularly challenging synthetic goals. The combination of their destabilizing features hinders attempts to prepare molecules such as pentalyne, an 8p-electron anti- aromatic bicycle with extremely high ring strain. Here we describe the facile synthesis of osmapentalyne derivatives that are thermally viable, despite containing the smallest angles observed so far at a carbyne carbon. The compounds are characterized using X-ray crystallography, and their computed energies and magnetic properties reveal aromatic character. Hence, the incorporation of the osmium centre not only reduces the ring strain of the parent pentalyne, but also converts its Hu¨ckel anti-aromaticity into Craig-type Mo¨bius aromaticity in the metallapentalynes. The concept of aromaticity is thus extended to five-membered rings containing a metal–carbon triple bond. Moreover, these metal–aromatic compounds exhibit unusual optical effects such as near-infrared photoluminescence with particularly large Stokes shifts, long lifetimes and aggregation enhancement. romaticity is a fascinating topic that has long interested Results and discussion both experimentalists and theoreticians because of its ever- Synthesis, characterization and reactivity of osmapentalynes. Aincreasing diversity1–5. The Hu¨ckel aromaticity rule6 applies Treatment of complex 1 (ref. 32) with methyl propiolate to cyclic circuits of 4n þ 2 mobile electrons, but Mo¨bius topologies (HC;CCOOCH3) at room temperature produced osmapentalyne favour 4n delocalized electron counts7–10. -
Deoxydehydration of Vicinal Diols by Homogeneous Catalysts: a Mechanistic Overview
Deoxydehydration of vicinal diols by homogeneous royalsocietypublishing.org/journal/rsos catalysts: a mechanistic overview Review Cite this article: DeNike KA, Kilyanek SM. 2019 Kayla A. DeNike and Stefan M. Kilyanek Deoxydehydration of vicinal diols by homogeneous catalysts: a mechanistic overview. Department of Chemistry and Biochemistry, University of Arkansas, 1 University of Arkansas, Fayetteville, AR 727001, USA R. Soc. open sci. 6: 191165. http://dx.doi.org/10.1098/rsos.191165 SMK, 0000-0002-6179-2510 Received: 4 July 2019 Deoxydehydration (DODH) is an important reaction for the Accepted: 4 October 2019 upconversion of biomass-derived polyols to commodity chemicals such as alkenes and dienes. DODH can be performed Subject Category: by a variety of early metal-oxo catalysts incorporating Re, Mo and V. The varying reduction methods used in the DODH Chemistry catalytic cycle impact the product distribution, reaction Subject Areas: mechanism and the overall yield of the reaction. This review surveys the reduction methods commonly used in homogeneous inorganic chemistry/organometallic chemistry/ DODH catalyst systems and their impacts on yield and reaction green chemistry conditions. Keywords: deoxydehydration, catalysis, biomass upconversion, early metal-oxo 1. Introduction Due to the long-term implications for the climate of continuing to Author for correspondence: consume non-renewable carbon resources, such as oil, the Stefan M. Kilyanek decarbonization of the economy has become the topic of e-mail: [email protected] significant public and scientific concern [1,2]. As a result, the development of processes to produce valuable carbon-based commodity chemicals from renewable carbon feedstocks has become an important field of study [3]. -
Bond Distances and Bond Orders in Binuclear Metal Complexes of the First Row Transition Metals Titanium Through Zinc
Metal-Metal (MM) Bond Distances and Bond Orders in Binuclear Metal Complexes of the First Row Transition Metals Titanium Through Zinc Richard H. Duncan Lyngdoh*,a, Henry F. Schaefer III*,b and R. Bruce King*,b a Department of Chemistry, North-Eastern Hill University, Shillong 793022, India B Centre for Computational Quantum Chemistry, University of Georgia, Athens GA 30602 ABSTRACT: This survey of metal-metal (MM) bond distances in binuclear complexes of the first row 3d-block elements reviews experimental and computational research on a wide range of such systems. The metals surveyed are titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper, and zinc, representing the only comprehensive presentation of such results to date. Factors impacting MM bond lengths that are discussed here include (a) n+ the formal MM bond order, (b) size of the metal ion present in the bimetallic core (M2) , (c) the metal oxidation state, (d) effects of ligand basicity, coordination mode and number, and (e) steric effects of bulky ligands. Correlations between experimental and computational findings are examined wherever possible, often yielding good agreement for MM bond lengths. The formal bond order provides a key basis for assessing experimental and computationally derived MM bond lengths. The effects of change in the metal upon MM bond length ranges in binuclear complexes suggest trends for single, double, triple, and quadruple MM bonds which are related to the available information on metal atomic radii. It emerges that while specific factors for a limited range of complexes are found to have their expected impact in many cases, the assessment of the net effect of these factors is challenging. -
Catalytic Organic Transformations Mediated by Actinide Complexes
Inorganics 2015, 3, 392-428; doi:10.3390/inorganics3040392 OPEN ACCESS inorganics ISSN 2304-6740 www.mdpi.com/journal/inorganics Review Catalytic Organic Transformations Mediated by Actinide Complexes Isabell S. R. Karmel, Rami J. Batrice and Moris S. Eisen * Schulich Faculty of Chemistry, Technion—Israel Institute of Technology, Technion City, Haifa 32000, Israel; E-Mails: [email protected] (I.S.R.K.); [email protected] (R.J.B.) * Author to whom correspondence should be addressed; E-Mail: [email protected]; Tel./Fax: +972-4-829-2680. Academic Editors: Stephen Mansell and Steve Liddle Received: 16 September 2015 / Accepted: 9 October 2015 / Published: 30 October 2015 Abstract: This review article presents the development of organoactinides and actinide coordination complexes as catalysts for homogeneous organic transformations. This chapter introduces the basic principles of actinide catalysis and deals with the historic development of actinide complexes in catalytic processes. The application of organoactinides in homogeneous catalysis is exemplified in the hydroelementation reactions, such as the hydroamination, hydrosilylation, hydroalkoxylation and hydrothiolation of alkynes. Additionally, the use of actinide coordination complexes for the catalytic polymerization of α-olefins and the ring opening polymerization of cyclic esters is presented. The last part of this review article highlights novel catalytic transformations mediated by actinide compounds and gives an outlook to the further potential of this field. Keywords: organoactinides; actinide coordination complexes; homogeneous catalysis; hydroelementations; polymerization of olefins; ROP; activation of heterocumulenes 1. Introduction The beginning of modern organoactinide chemistry is often attributed to the synthesis of 8 uranocene, [(η -C8H8)2U] in 1968, as the analogous compound to ferrocene and other transition metal metallocenes [1,2]. -
Supporting Information
Supplementary Material (ESI) for Chemical Communications This journal is © The Royal Society of Chemistry 2008 Supporting information Thermal cyclotrimerization of tetraphenyl[5]cumulene (tetraphenylhexapentaene) to tricyclodecadiene derivative † Nazrul Islam, Takashi Ooi , Tetsuo Iwasawa, Masaki Nishiuchi and Yasuhiko * Kawamura Institute of Technology and Science, The University of Tokushima, 2-1 Minamijosanjima-cho, Tokushima 770-8506, Japan †Institute of Health Biosciences, The University of Tokushima, 1-78 Shomachi, Tokushima 770-8505, Japan *Corresponding author. E-mail: [email protected] Experimental section 1. General Methods: Chemicals were obtained from Tokyo Kasei (Tokyo Chemical Industry), Wako (Wako Pure Chemical Industries), Aldrich, and Merck and used as received if not specified 1 13 otherwise. H NMR and C NMR spectra were recorded in CDCl3 on a JEOL EX-400 spectrometer with TMS as an internal standard. HPLC analysis was performed on a JASCO high-performance liquid chromatography system equipped with a 4.6 x 250 mm silica gel column (JASCO Finepak® SIL) and a HITACHI diode array detector (HITACHI L-2450; detector wavelength = 254 nm; mobile phase, CH3CN : H2O = 8:2 v/v). UV-VIS spectra were measured with a Hitachi UV-2000 spectrophotometer. Mass spectra were determined by a Shimadzu GC-MS QP-1000 with a direct inlet attachment using an ionizing voltage of 20 and 70 eV. Elemental analyses were performed by using Yanoco MT-5 instrument at the microanalytical laboratory of this university. X-ray crystallographic analysis was performed with a Rigaku RAXIS-RAPID instrument 1 Supplementary Material (ESI) for Chemical Communications This journal is © The Royal Society of Chemistry 2008 (Rigaku Corporation). -
Arenechromium Tricarbonyl Complexes: Conformational
η6 – ARENECHROMIUM TRICARBONYL COMPLEXES: CONFORMATIONAL ANALYSIS, STEREOCONTROL IN NUCLEOPHILIC ADDITION AND APPLICATIONS IN ORGANIC SYNTHESIS by HARINANDINI PARAMAHAMSAN Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy Thesis Advisor: Prof. Anthony J. Pearson Department of Chemistry CASE WESTERN RESERVE UNIVERSITY May 2005 CASE WESTERN RESERVE UNIVERSITY SCHOOL OF GRADUATE STUDIES We hereby approve the dissertation of Harinandini Paramahamsan candidate for the Ph.D. degree*. (signed) Prof. Philip P. Garner (Chair of the Committee, Department of Chemistry, CWRU) Prof. Anthony J. Pearson (Department of Chemistry, CWRU) Prof. Fred L. Urbach (Department of Chemistry, CWRU) Dr. Zwong-Wu Guo (Department of Chemistry, CWRU) Dr. Stuart J. Rowan (Department of Macromolecular Science and Engineering, CWRU) Date: 14th January 2005 *We also certify that written approval has been obtained for any propriety material contained therein. To Amma, Naina & all my Teachers Table of Contents List of Tables………………………………………………………………………..……iv List of Figures…………………………………………………………………….…........vi List of Schemes…………………………………………………………………….….….ix List of Equations………………………………………………………...……….……….xi Acknowledgements………………………………………………………….…..……….xii List of Abbreviations……………………………………………………………………xiv Abstract………………………………………………………………………………….xvi CHAPTER I........................................................................................................................ 1 I.1 Structure and Bonding ........................................................................................... -
United States Patent (19) 11 Patent Number: 5,342,985 Herrmann Et Al
USOO5342985A United States Patent (19) 11 Patent Number: 5,342,985 Herrmann et al. (45. Date of Patent: Aug. 30, 1994 54) ORGANIC DERIVATIVES OF RHENIUM 58 Field of Search ................ 556/482, 485; 560/130, OXDES AND THER PREPARATION AND 560/219, 221, 205; 568/626, 627, 630, 655, 685, USE FOR THE METATHESS OF OLEFENS 687; 570/135, 136; 585/510,520 75 Inventors: Wolfgang A. Herrmann, Freising: Primary Examiner-Paul F. Shaver Werner Wagner, Munich; Ursula Attorney, Agent, or Firm-Connolly & Hutz Volkhardt, Freising, all of Fed. Rep. of Germany 57 ABSTRACT 73) Assignee: Hoechst AG, Frankfurt am Main, The invention relates to a process for the metathesis of Fed. Rep. of Germany olefins which comprises reacting an olefin of the for mula YCZ=CZ-(CX2),R2 (II) wherein 21 Appl. No.: 569,614 n is an integer from 1 to 28, 22 Filed: Aug. 20, 1990 X represents H or F, Y represents H or alkyl having from 1 to 10 carbon Related U.S. Application Data atoms and 63 Continuation-in-part of Ser. No. 320,404, Mar. 8, 1989, Z represents Hor a non-aromatic hydrocarbon group abandoned. having from 1 to 6 carbon atoms and R2 represents a H, alkyl, halogen, COOR3 or OR', wherein R3and 30 Foreign Application Priority Data R4 represent alkyl having from 1 to 15 carbon Dec. 10, 1988 DE Fed. Rep. of Germany ....... 384,733 atoms or phenyl which is unsubstituted or contains Jan. 31, 1989 IDE Fed. Rep. of Germany ....... 3902787 from 1 to 3 substituents or wherein R is trialkylsi Mar. -
Synthesis of Fused and Bridged Ring Systems James Nicolas Ong Sy Iowa State University
Iowa State University Capstones, Theses and Retrospective Theses and Dissertations Dissertations 1988 Synthesis of fused and bridged ring systems James Nicolas Ong Sy Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/rtd Part of the Organic Chemistry Commons Recommended Citation Sy, James Nicolas Ong, "Synthesis of fused and bridged ring systems " (1988). Retrospective Theses and Dissertations. 9735. https://lib.dr.iastate.edu/rtd/9735 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 Retrospective Theses and Dissertations by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. INFORMATION TO USERS The most advanced technology has been used to photo graph and reproduce this manuscript from the microfilm master. UMI films the original text directly from the copy submitted. Thus, some dissertation copies are in typewriter face, while others may be from a computer printer. In the unlikely event that the author did not send UMl a complete manuscript and there are missing pages, these will be noted. Also, if unauthorized copyrighted material had to be removed, a note will indicate the deletion. Oversize materials (e.g., maps, drawings, charts) are re produced by sectioning the original, beginning at the upper left-hand comer and continuing from left to right in equal sections with small overlaps. Each oversize page is available as one exposure on a standard 35 mm slide or as a 17" x 23" black and white photographic print for an additional charge.