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CO2 Derivatives of Molecular Tin Compounds. Part 1: † Hemicarbonato and Carbonato Complexes
inorganics Review CO2 Derivatives of Molecular Tin Compounds. Part 1: y Hemicarbonato and Carbonato Complexes Laurent Plasseraud Institut de Chimie Moléculaire de l’Université de Bourgogne (ICMUB), UMR-CNRS 6302, Université de Bourgogne Franche-Comté, 9 avenue A. Savary, F-21078 Dijon, France; [email protected] Paper dedicated to Professor Georg Süss-Fink on the occasion of his 70th birthday. y Received: 31 March 2020; Accepted: 24 April 2020; Published: 29 April 2020 Abstract: This review focuses on organotin compounds bearing hemicarbonate and carbonate ligands, and whose molecular structures have been previously resolved by single-crystal X-ray diffraction analysis. Most of them were isolated within the framework of studies devoted to the reactivity of tin precursors with carbon dioxide at atmospheric or elevated pressure. Alternatively, and essentially for the preparation of some carbonato derivatives, inorganic carbonate salts such as K2CO3, Cs2CO3, Na2CO3 and NaHCO3 were also used as coreagents. In terms of the number of X-ray structures, carbonate compounds are the most widely represented (to date, there are 23 depositions in the Cambridge Structural Database), while hemicarbonate derivatives are rarer; only three have so far been characterized in the solid-state, and exclusively for diorganotin complexes. For each compound, the synthesis conditions are first specified. Structural aspects involving, in particular, the modes of coordination of the hemicarbonato and carbonato moieties and the coordination geometry around tin are then described and illustrated (for most cases) by showing molecular representations. Moreover, when they were available in the original reports, some characteristic spectroscopic data are also given for comparison (in table form). -
EI-ICHI NEGISHI Herbert C
MAGICAL POWER OF TRANSITION METALS: PAST, PRESENT, AND FUTURE Nobel Lecture, December 8, 2010 by EI-ICHI NEGISHI Herbert C. Brown Laboratories of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, IN 47907-2084, U.S.A. Not long ago, the primary goal of the synthesis of complex natural products and related compounds of biological and medicinal interest was to be able to synthesize them, preferably before anyone else. While this still remains a very important goal, a number of today’s top-notch synthetic chemists must feel and even think that, given ample resources and time, they are capable of synthesizing virtually all natural products and many analogues thereof. Accepting this notion, what would then be the major goals of organic synthesis in the twenty-first century? One thing appears to be unmistakably certain. Namely, we will always need, perhaps increasingly so with time, the uniquely creative field of synthetic organic and organometallic chemistry to prepare both new and existing organic compounds for the benefit and well-being of mankind. It then seems reasonably clear that, in addition to the question of what compounds to synthesize, that of how best to synthesize them will become increasingly important. As some may have said, the primary goal would then shift from aiming to be the first to synthesize a given compound to seeking its ultimately satisfactory or “last synthesis”. If one carefully goes over various aspects of organic synthetic methodology, one would soon note how primitive and limited it had been until rather recently, or perhaps even today. For the sake of argument, we may propose here that the ultimate goal of organic synthesis is “to be able to synthesize any desired and fundamentally synthesizable organic compounds (a) in high yields, (b) efficiently (in as few steps as possible, for example), (c) selectively, preferably all in t98–99% selectivity, (d) economically, and (e) safely, abbreviated hereafter as the y(es)2 manner.” with or without catalyst R1M + R2X R1R2 + MX R1, R2: carbon groups. -
Catalytic Systems Based on Cp2zrx2 (X = Cl, H), Organoaluminum
catalysts Article Catalytic Systems Based on Cp2ZrX2 (X = Cl, H), Organoaluminum Compounds and Perfluorophenylboranes: Role of Zr,Zr- and Zr,Al-Hydride Intermediates in Alkene Dimerization and Oligomerization Lyudmila V. Parfenova 1,* , Pavel V. Kovyazin 1, Almira Kh. Bikmeeva 1 and Eldar R. Palatov 2 1 Institute of Petrochemistry and Catalysis of Russian Academy of Sciences, Prospekt Oktyabrya, 141, 450075 Ufa, Russia; [email protected] (P.V.K.); [email protected] (A.K.B.) 2 Bashkir State University, st. Zaki Validi, 32, 450076 Ufa, Russia; [email protected] * Correspondence: [email protected]; Tel.: +7-347-284-3527 i i Abstract: The activity and chemoselectivity of the Cp2ZrCl2-XAlBu 2 (X = H, Bu ) and [Cp2ZrH2]2- ClAlEt2 catalytic systems activated by (Ph3C)[B(C6F5)4] or B(C6F5)3 were studied in reactions with 1-hexene. The activation of the systems by B(C6F5)3 resulted in the selective formation of head- to-tail alkene dimers in up to 93% yields. NMR studies of the reactions of Zr complexes with organoaluminum compounds (OACs) and boron activators showed the formation of Zr,Zr- and Zr,Al-hydride intermediates, for which diffusion coefficients, hydrodynamic radii, and volumes were estimated using the diffusion ordered spectroscopy DOSY. Bis-zirconium hydride clusters of type x[Cp ZrH ·Cp ZrHCl·ClAlR ]·yRnAl(C F ) − were found to be the key intermediates of alkene 2 2 2 2 6 5 3 n dimerization, whereas cationic Zr,Al-hydrides led to the formation of oligomers. Citation: Parfenova, L.V.; Kovyazin, P.V.; Bikmeeva, A.K.; Palatov, E.R. -
Of Grignard Reagent Formation. the Surface Nature of the Reaction
286 Ace. Chem. Res. 1990,23, 286-293 Mechanism of Grignard Reagent Formation. The Surface Nature of the Reaction H. M. WALBORSKY Dittmer Laboratory of Chemistry, Florida State University, Tallahassee, Florida 32306 Received February 23, 1990 (Revised Manuscript Received May 7, 1990) The reaction of organic halides (Br, C1, I) with mag- Scheme I nesium metal to yield what is referred to today as a Kharasch-Reinmuth Mechanism for Grignard Reagent Grignard reagent has been known since the turn of the Formation century,' The name derives from its discoverer, Nobel (1)(Mg0)AMg*)2y + RX 4 [(M~'~(MQ')~~-,('MQX)+ R.] + laureate Victor Grignard. How this reagent is formed, (Mgo)x-2(MQ')2~MgX)(MgR) that is, how a magnesium atom is inserted into a car- bon-halogen bond, is the subject of this Account. ('4 (Ms0),-*(M9')2~MgX)(MgR) + + (Mg0)x-dMg*)2y+2 + 2RMgX RX + Mg - RMgX Kharasch and Reinmuth,, persuaded by the work of late under the same conditions gave Itl = 6.2 X s-l. Another system that meets the above criterion is the Gomberg and Bachmad as well as by product analyses of many Grignard formation reactions that existed in vinyl system. The lack of reactivity of vinyl halides toward SN1reactions is well-known and is exemplified the literature prior to 1954,speculated that the reaction involved radicals and that the radical reactions might by the low solvolysis rate of 2-propenyl triflate5 in 80% involve "surface adherent radicals, at least in part". The ethanol at 25 OC, kl being 9.8 X s-l. -
Organometrallic Chemistry
CHE 425: ORGANOMETALLIC CHEMISTRY SOURCE: OPEN ACCESS FROM INTERNET; Striver and Atkins Inorganic Chemistry Lecturer: Prof. O. G. Adeyemi ORGANOMETALLIC CHEMISTRY Definitions: Organometallic compounds are compounds that possess one or more metal-carbon bond. The bond must be “ionic or covalent, localized or delocalized between one or more carbon atoms of an organic group or molecule and a transition, lanthanide, actinide, or main group metal atom.” Organometallic chemistry is often described as a bridge between organic and inorganic chemistry. Organometallic compounds are very important in the chemical industry, as a number of them are used as industrial catalysts and as a route to synthesizing drugs that would not have been possible using purely organic synthetic routes. Coordinative unsaturation is a term used to describe a complex that has one or more open coordination sites where another ligand can be accommodated. Coordinative unsaturation is a very important concept in organotrasition metal chemistry. Hapticity of a ligand is the number of atoms that are directly bonded to the metal centre. Hapticity is denoted with a Greek letter η (eta) and the number of bonds a ligand has with a metal centre is indicated as a superscript, thus η1, η2, η3, ηn for hapticity 1, 2, 3, and n respectively. Bridging ligands are normally preceded by μ, with a subscript to indicate the number of metal centres it bridges, e.g. μ2–CO for a CO that bridges two metal centres. Ambidentate ligands are polydentate ligands that can coordinate to the metal centre through one or more atoms. – – – For example CN can coordinate via C or N; SCN via S or N; NO2 via N or N. -
Submitted to the Requirements For
THE SYNTIIE$IS OP C LABELLED 2, 4-DICI LOROi-EENOÇYAGETIC ACID by ERNEST GEORGE AWORSKI A THESIS submitted to OREGON STA1 COLLEGE in partial fulfillment or the requirements for the degree of MAS2R 0F SCIENCE June 1950 PROVED: professor ot Clie'thlstry Department In Charge of Major Head of Department of' Chemistry Chairman of School Graduate Conimittee Dean of Graduate School Date thesis is presented Typed by Clara Homyar ACNOWLEDGMNTS The author wishes to express his appreciation to Dr. oseph S. Butts for his eneouragem.ent and generous direction in r4laking this work possible. Grateful aoknowledgnient is given to Dr. Albert V. Logan for his assistance in methodical diff i- culties. This research project was supported by an Atoniic inergy Commission grant carried under Navy contract N7-onr-3 7602. TABLE OF CONTENTS Page I. INTRODUCTION I II. STNTHESI OF ALPHA METH'LENB LABELLED2,14-D . , * 4 A. Apparatus ......*,*., B Method . 7 C. Analysis and }hysica1 Constants 3.7 In. StfliSIs OF C CABBOXTh LABELLED 2LD 19 A. Apparatus . 19 B )kethoc3. , , , , , 23. C. Analysis and PhjsLoa3. Constants 26 Iv DISCUSSION . , , . , , V. SUL2&RY . e e . 30 LTTERATUREOITED .......... 31 I1N1)I. 3 2 THE SYNTHESIS OF C LABELLED 2, 4-DICHLOROHENOXThCETIC ACID I. INTRODUCTION The synthesis or C labelled 2,4-dichlorophen- oxyacetic acid (hereafter referred to as 2,4V-D) was undertaken In order to study the process by which lt exerts its selective herbicidal effect on soiae noxious plants. Should this method prove fruitful, it would be useful for a more systematic approach to the study of ooitounds having potential herbicidal properties. -
Cyclopentadienyl Compounds of the First Row Transition Metals And
University of Vermont ScholarWorks @ UVM Graduate College Dissertations and Theses Dissertations and Theses 2017 Cyclopentadienyl Compounds of the First Row Transition Metals and Early Actinides: Novel Main-Group Bond Forming Catalysis and New Metallacycles Justin Kane Pagano University of Vermont Follow this and additional works at: https://scholarworks.uvm.edu/graddis Part of the Chemistry Commons Recommended Citation Pagano, Justin Kane, "Cyclopentadienyl Compounds of the First Row Transition Metals and Early Actinides: Novel Main-Group Bond Forming Catalysis and New Metallacycles" (2017). Graduate College Dissertations and Theses. 700. https://scholarworks.uvm.edu/graddis/700 This Dissertation is brought to you for free and open access by the Dissertations and Theses at ScholarWorks @ UVM. It has been accepted for inclusion in Graduate College Dissertations and Theses by an authorized administrator of ScholarWorks @ UVM. For more information, please contact [email protected]. CYCLOPENTADIENYL COMPOUNDS OF THE FIRST ROW TRANSITION METALS AND EARLY ACTINIDES: NOVEL MAIN-GROUP BOND FORMING CATALYSIS AND NEW METALLACYCLES A Dissertation Presented by Justin Kane Pagano to The Faculty of the Graduate College of The University of Vermont In Partial Fulfilment of the Requirements For the Degree of Doctor of Philosophy Specializing in Chemistry May, 2017 Defense Date: November 29, 2016 Dissertation Examination Committee: Rory Waterman, Ph. D., Advisor John M. Hughes, Ph. D., Chairperson Matthias Brewer, Ph. D. Jaqueline L. Kiplinger, Ph. D. Matthew D. Liptak, Ph. D. Cynthia J. Forehand, Ph. D., Dean of the Graduate College ABSTRACT Cyclopentadienyl first row transition-metal compounds have been well studied 5 since the 1950’s, with the nearly ubiquitous CpFe(CO)2Me (FpMe) (Cp = η -C5H5) being one of the first organometallics to be fully characterized. -
![Preparation of “Constrained Geometry” Titanium Complexes of [1,2]Azasilinane Framework for Ethylene/1-Octene Copolymerization](https://docslib.b-cdn.net/cover/5079/preparation-of-constrained-geometry-titanium-complexes-of-1-2-azasilinane-framework-for-ethylene-1-octene-copolymerization-825079.webp)
Preparation of “Constrained Geometry” Titanium Complexes of [1,2]Azasilinane Framework for Ethylene/1-Octene Copolymerization
molecules Article Preparation of “Constrained Geometry” Titanium Complexes of [1,2]Azasilinane Framework for Ethylene/1-Octene Copolymerization Seul Lee, Seung Soo Park, Jin Gu Kim, Chung Sol Kim and Bun Yeoul Lee * Department of Molecular Science and Technology, Ajou University, Suwon 443-749, Korea; [email protected] (S.L.); [email protected] (S.S.P.); [email protected] (J.G.K.); [email protected] (C.S.K.) * Correspondence: [email protected]; Tel.: +82-031-219-1844 Academic Editor: Kotohiro Nomura Received: 27 December 2016; Accepted: 7 February 2017; Published: 9 February 2017 5 t Abstract: The Me2Si-bridged ansa-Cp/amido half-metallocene, [Me2Si(η -Me4C5)(N Bu)]TiCl2, termed a “constrained-geometry catalyst (CGC)”, is a representative homogeneous Ziegler catalyst. CGC derivatives with the [1,2]azasilinane framework, in which the amide alkyl substituent is joined by the Si-bridge, were prepared, and the catalytic performances of these species was studied. Me4C5HSi(Me)(CH2CH=CH2)-NH(C(R)(R’)CH=CH2) (R, R’ = H or methyl; Me4C5H = tetramethylcyclopentadienyl) was susceptible to ring closure metathesis (RCM) when treated with Schrock’s Mo-catalyst to afford -Si(Me4C5H)(Me)CH2CH=CHC(R)(R’)NH- containing a six-membered ring framework. Using the precursors and the products of RCM, various CGC derivatives, i.e., 5 5 [-Si(η -Me4C5)(Me)CH2CH=CHC(R)(H)N-]TiMe2 (13, R = H; 15, R = Me), [-Si(η -Me4C5)(Me) 5 CH2CH2CH2CH2N]TiMe2 (14), [(η -Me4C5)Si(Me)(CH2CH=CH2)NCH2CH=CH2]TiMe2 (16), 5 5 [(η -Me4C5)Si (Me)(CH=CH2)NCH2CH=CH2]TiMe2 (17), and [(η -Me4C5)Si(Me)(CH2CH3)NCH2 CH2CH3]TiMe2 (18), were prepared. -
Part I. Inversion of Secondary Cyclic Grignard Reagents
This dissertation has been , 69-11,692 microfilmed exactly as received PECHHOLD, Engelbert, 1933- STUDIES OF THE BEHAVIOR AND GENERATION OF GARB ANIONS: PART I. INVERSION OF SECONDARY CYCLIC GRIGNARD REAGENTS. PART II. FRAGMENTATION OF AZOFORMATE SALTS AND ACYLAZO COMPOUNDS WITH BASES. The Ohio State University, Ph.D., 1968 Chemistry, organic University Microfilms, Inc., Ann Arbor, Michigan ©Copyright "by- Engelbert Pechhold 1969 STUDIES OF THE BEHAVIOR MD GENERATION OF CARBANIONS PART I. INVERSION OF SECONDARY CYCLIC GRIGNARD REAGENTS PART II. FRAGMENTATION OF AZOFORMATE SADIS AND ACYLAZO COMPOUNDS WITH BASES DISSERTATION Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University By Engelbert Pechhold * # # * * # The Ohio State University 1968 Approved by •pV-gpa.-t— Adviser Department of Chemistry DEDICATION To my wife, Ingrid, and my parents, whose love, understanding, and encouragement have made this venture possible. ii ACKNOWLEDaEMElWS I -wish to express my deepest appreciation to Professor Gideon Fraenkel for suggestinf^ this problem, and for his guidance and encouragement throughout the course of this research. His assistance in the preparation of this dissertation is gratefully acknowledged. It is an understatement to say that without his un usual courage of conviction and high standards for academic perfor mance, this work could not have come into being. I owe special debt of gratitude to my colleagues for many suimtü-ating discussions of chemical matters and otherwise. In particular, I wish to express my gratitute to Dr. Don Dix, Dr. Dave Mams, and James Morton, who gave me much insight in ny research. -
Materials Properties Derived from INSITE Metallocene Catalysts
REVIEW Materials Properties Derived from INSITE Metallocene Catalysts By P. Stephen Chum,* William J. Kruper, and Martin J. Guest Novel metallocene catalysts for the synthesis of ethylene/a-olefin copolymers are reviewed here. The technology usedÐsingle-site constrained geometry catalyst technologyÐis demonstrated to be useful for the preparation of a wide array of copolymers with unique materials properties, such as a high melt fracture resistance, as illustrated in the Figure. 1. General Aspects and Challenges of Catalysis procatalyst is inactive for olefin polymerization and may be activated through the use of Lewis acid catalysis with mixtures Over the past decade, the development of Dow's INSITE of modified methylalumoxane (MMAO) and electron-defi- (trademark of The Dow Chemical Co.) metallocene catalysts cient boranes such as tris-perfluorophenylborane (FAB). Al- has led to the launch of many new polyolefin product lines ternatively, the procatalyst may be activated through the use that had been previously unattainable from conventional of preformed, non-coordinating counterions, which are appro- Ziegler±Natta catalysis.[1] From a structure±activity perspec- priately ion-paired with protonated ammonium or trityl salts. IV tive, the catalyst ligand structures are readily tailored synthet- The nature of the catalytically active species derived from Ti ically from both an electronic and steric point of view. This analogues under polymerization conditions has recently been [4] alteration motif has led to the development and screening of reviewed. It is clear from our studies that variation of the several hundred ansa-cyclopentadienyl amido group IV metal Lewis acid components of the catalyst package can affect constrained-geometry catalysts (CGCs), which have been parameters such as efficiency, comonomer incorporation, Mw, evaluated for the preparation of a wide array of ethylene/ polydispersity, and more importantly, polymer microstructure a-olefin copolymers possessing unique materials properties.[2] and stereoregularity. -
Carbonation of a Grignard Preparation of Benzoic Acid
CARBONATION OF A GRIGNARD PREPARATION OF BENZOIC ACID INTRODUCTION The Grignard is one of the most versatile reactions in organic chemistry. It was used to produce 2-methyl-2-hexanol from bromobutane and acetone. Carboxylic acids may also be prepared by the Grignard reagent. The “Grignard” is an organometallic compound that contains one the most powerful nucleophiles. This carbanion is capable of reacting with something that is only slightly basic like carbon dioxide. This reaction will convert bromobenzene to benzoic acid. The bromobenzene is converted to the Grignard and then added to solid carbon dioxide. The carbon dioxide acts as a reactant and as the means to keep the reaction cold. The Grignard is prepared by the process of reflux with addition. In this reaction the glassware and reactants must be kept absolutely dry, as the presence of water will inhibit the reaction. Reactions: Br MgBr Ether + Mg MgBr COOH + H3O + CO2 Week One PROCEDURE 1. PREPARATION OF THE GRIGNARD REAGENT Add 0.1 mole of Mg metal ( 2.43 grams ) to a 100 ml round bottom flask and add 30 ml of anhydrous ether to cover the metal. Clamp the flask to the grid at a height that will allow enough room for heating and cooling. Add 0.1 mole of bromobenzene to a separatory funnel. Attach a Claisen adapter to the round bottom flask and fit the adapter just above with a water cooled column. Attach the separatory funnel to the other connection. Prepare an ice/water bath and position it so that the reaction mixture may be cooled by raising the bath to the round bottom with a lab jack. -
Synthesis and Reactivity of Cyclopentadienyl Based Organometallic Compounds and Their Electrochemical and Biological Properties
Synthesis and reactivity of cyclopentadienyl based organometallic compounds and their electrochemical and biological properties Sasmita Mishra Department of Chemistry National Institute of Technology Rourkela Synthesis and reactivity of cyclopentadienyl based organometallic compounds and their electrochemical and biological properties Dissertation submitted to the National Institute of Technology Rourkela In partial fulfillment of the requirements of the degree of Doctor of Philosophy in Chemistry by Sasmita Mishra (Roll Number: 511CY604) Under the supervision of Prof. Saurav Chatterjee February, 2017 Department of Chemistry National Institute of Technology Rourkela Department of Chemistry National Institute of Technology Rourkela Certificate of Examination Roll Number: 511CY604 Name: Sasmita Mishra Title of Dissertation: ''Synthesis and reactivity of cyclopentadienyl based organometallic compounds and their electrochemical and biological properties We the below signed, after checking the dissertation mentioned above and the official record book(s) of the student, hereby state our approval of the dissertation submitted in partial fulfillment of the requirements of the degree of Doctor of Philosophy in Chemistry at National Institute of Technology Rourkela. We are satisfied with the volume, quality, correctness, and originality of the work. --------------------------- Prof. Saurav Chatterjee Principal Supervisor --------------------------- --------------------------- Prof. A. Sahoo. Prof. G. Hota Member (DSC) Member (DSC) ---------------------------