Schlenk Equilibrium in Toluene Solutions of Grignard Reagents
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Magnesium Causes Nitric Oxide Independent Coronary Artery Vasodilation in Humans Heart: First Published As 10.1136/Hrt.86.2.212 on 1 August 2001
212 Heart 2001;86:212–216 Magnesium causes nitric oxide independent coronary artery vasodilation in humans Heart: first published as 10.1136/hrt.86.2.212 on 1 August 2001. Downloaded from H Teragawa, M Kato, T Yamagata, H Matsuura, G Kajiyama Abstract Objective—To determine how magnesium aVects human coronary arteries and whether endothe- lium derived nitric oxide (EDNO) is involved in the coronary arterial response to magnesium. Design—Quantitative coronary angiography and Doppler flow velocity measurements were used to determine the eVects of the nitric oxide synthase inhibitor NG-monomethyl-L-arginine (L-NMMA) on magnesium induced dilation of the epicardial and resistance coronary arteries. Setting—Hiroshima University Hospital a tertiary cardiology centre. Patients—17 patients with angiographically normal coronary arteries. Interventions—Magnesium sulfate (MgSO4) (0.02 mmol/min and 0.2 mmol/min) was infused for two minutes into the left coronary ostium before and after intracoronary infusion of L-NMMA. Main outcome measures—Diameter of the proximal and distal segments of the epicardial cor- onary arteries and coronary blood flow. Results—At a dose of 0.02 mmol/min, MgSO4 did not aVect the coronary arteries. At a dose of 0.2 mmol/min, MgSO4 caused coronary artery dilation (mean (SEM) proximal diameter 3.00 (0.09) to 3.11 (0.09) mm; distal 1.64 (0.06) to 1.77 (0.07) mm) and increased coronary blood flow (79.3 (7.5) to 101.4 (9.9) ml/min, p < 0.001 v baseline for all). MgSO4 increased the changes in these parameters after the infusion of L-NMMA (p < 0.001 v baseline). -
THE ACCUMULATION and DISTRIBUTION of EVANS BLUE in the KIDNEY of RATS FED NORMAL OR LOW MAGNESIUM DIETS by George Williams Seign
THE ACCUMULATION AND DISTRIBUTION OF EVANS BLUE IN THE KIDNEY OF RATS FED NORMAL OR LOW MAGNESIUM DIETS by George Williams Seignious, IV Thesis submitted to the Graduate Faculty of the Virginia Polytechnic Institute and State University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE in ! Biochemistry and Nutrition APPROVED: G. E. Bunce, Chairman R. E. Webb ______ fl" ________ M;O. ......... ..;:;...; ___'"";:,....:; __.;..,. ___ _ _.. ''-.::;,,/ ___ , _______ ,_.._~_ M. H. Samli R. G. Saacke August, 1973 Blacksburg, Virginia . l\CKNOWLEDGMEN',rS The author of this thesis would like to e~press his deepest thanks and gra'titU;de to for his.continued help, advice, and . ·. .. : .. - understanding which made this thesis possible •. A special note of ·"· thanks is expressed.to whos_e invaluable help, advice arid suggestions aided greatly the author's efforts. The author would also like to thank for his. help and advice in the lab and all the other graduate students who made the author's stay at Virginia.Tech i{ very pleasant _one. Thanks is expressed to the author's wife, , for .her love, understanding, encouragement, and typing which· enabled the completion of this thesis. Also the author would like.to thank his parents for their lc;rving support and financial assistance. ii 'TABLE OF CONTENTS ACKNOWLEDGMENTS ii. TABLE OF CONTENTS . iii I,.IST OF TABLES iv LIST OF FIGURES Vi LIST OF SELECTED CHEMICAL STRUCTURES vii LIST OF·ABBREVIATIONS viii INTRODUCTION 1 LITERATURE REVIEW 5 EXPERIMENTAL PROCEDURES RESULTS 33 DISCUSSION 74 SUMMARY 82 REFERENCES 85 VITA 88 iii ~· ,,;. -
Addition of a Grignard Reagent to an Ester: Formation of a Tertiary Alcohol
Addition of a Grignard Reagent to an Ester: Formation of a Tertiary Alcohol Introduction: Grignard reagents are important and versatile reagents in organic chemistry. In this experiment, you will prepare a Grignard reagent and react it with an ester to prepare a tertiary alcohol. Specifically, in this reaction you will prepare phenyl magnesium bromide from bromobenzene and magnesium metal and then react it with methyl benzoate to prepare triphenylmethanol (Figure 1). In this reaction, two equivalents of phenylmagnesium bromide add to methyl benzoate. Note: Grignard reagents are sensitive to water. ALL glassware must be completely clean and dry. Reagents have been stored over molecular sieves to keep them dry in storage, but you should also keep containers closed as much as possible. Finally, water in the air can also react with the Grignard reagents over time. To successfully prepare triphenylmethanol in this experiment, you will need to be well organized and not take too much time between steps. Figure 1. O 1) Me O OH Br Mg MgBr THF + 2) H3O triphenylmethanol Mechanism: The formation of Grignard reagents from aryl halides is a complex mechanism, which takes place on the surface of the magnesium metal. You do not need to concern yourself with the details of this step of the mechanism. Figure 2. MgBr O Bu MgBr Bu MgBr O + OH O Bu MgBr O H3O Me OEt Bu Me OEt Me Bu Me Bu Me –EtOMgBr Bu Bu The mechanism of the reaction of a Grignard reagent with an ester is shown in Figure 2 (using methyl propionate and butylmagnesium bromide). -
Magnesium Production
Magnesium Production Subpart T, Greenhouse Gas Reporting Program Under the Greenhouse Gas Reporting Program (GHGRP), owners or operators of facilities that contain magnesium production processes must report emissions from use of cover and carrier gases as well as for all other source categories located at the facility for which methods are defined in the rule. Owners and operators are required to collect emission data, calculate greenhouse gas (GHG) emissions and follow the specified procedures for quality assurance, missing data, recordkeeping, and reporting per the requirements of 40 CFR Part 98 Subpart T – Magnesium Production. How Is This Source Category Defined? The magnesium production source category is defined as consisting of any process where magnesium metal is produced through smelting (including electrolytic smelting), refining, or remelting operations (including primary production facilities that extract magnesium from its ore and secondary production facilities that recover magnesium from scrap), or any process where molten magnesium is used in alloying, casting, drawing, extruding, forming, or rolling operations. Who Must Report? Magnesium production facilities that emit more than 25,000 metric tons CO2e per year. What Greenhouse Gases Must Be Reported? Each facility must report total annual emissions for each of the following greenhouse gases used in magnesium production facilities: ● Sulfur hexafluoride (SF6) ● HFC-134a ● The fluorinated ketone FK 5-1-12 ● Carbon dioxide (CO2) ● Any other GHG as defined in 40 CFR part 98, subpart A (General Provisions) of the rule In addition, the facility must report greenhouse gas emissions for any other source categories for which calculation methods are provided in the rule, as applicable. -
Copper(I) Complexes of P‐Stereogenic Josiphos and Related Ligands
Full Papers doi.org/10.1002/ejoc.202100146 Copper(I) Complexes of P-Stereogenic Josiphos and Related Ligands Ross A. Arthurs,[a] Alice C. Dean,[a] David L. Hughes,[a] and Christopher J. Richards*[a] Starting from (R)-Ugi’s amine, diastereoselective lithiation avoiding the isolation of air-sensitive phosphine intermediates. followed by Ar’PCl2 and then Ar’’MgBr led to the generation, as This protection methodology was also applied to the synthesis single diastereoisomers, of (R,Sp,Sphos) [Ar’=Ph, Ar’’=o-Tol] and of Josiphos/CuCl complexes derived from PCl3. In addition, (R,Sp,Rphos) [Ar’=o-Tol, Ar’’= Ph] PPFA ligand derivatives. Amine related bulky cobalt-sandwich complex-based derivatives were substitution of both with HPCy2 gave P-stereogenic Josiphos also obtained. Preliminary investigation revealed isolated CuCl ligands, and then addition of CuCl, the corresponding copper(I) complexes as competent catalyst precursors for enantioselec- complexes. The latter were also generated by using borane P tive conjugate addition reactions. and N protecting groups and in situ Cu(I) complexation, Introduction Although many ligands have been developed for application in asymmetric synthesis, relatively few have found widespread use. Of these so-called ‘privileged’ ligands,[1] one of the most successful class are the ferrocene-based Josiphos ligands A.[2] Numerous derivatives are known, obtained by varying the identity of R’ and R’’, and many are commercially available. This has aided the incorporation of A into many ligand screening exercises, often leading to a successful outcome.[3] In particular, in situ generated Josiphos-copper complexes have been applied Scheme 1. -
The Ozonolysis of Phenyl Grignard Reagent
University of Montana ScholarWorks at University of Montana Graduate Student Theses, Dissertations, & Professional Papers Graduate School 1971 The ozonolysis of phenyl Grignard reagent Gale Manning Sherrodd The University of Montana Follow this and additional works at: https://scholarworks.umt.edu/etd Let us know how access to this document benefits ou.y Recommended Citation Sherrodd, Gale Manning, "The ozonolysis of phenyl Grignard reagent" (1971). Graduate Student Theses, Dissertations, & Professional Papers. 8297. https://scholarworks.umt.edu/etd/8297 This Thesis is brought to you for free and open access by the Graduate School at ScholarWorks at University of Montana. It has been accepted for inclusion in Graduate Student Theses, Dissertations, & Professional Papers by an authorized administrator of ScholarWorks at University of Montana. For more information, please contact [email protected]. THE OZONOLYSIS OF PHENYL GRIGNARD REAGENT By Gale M. Sherrodd B.S., Rocky Mountain College, I969 Presented in partial fulfillment of the requirements for the degree of Master of Arts for Teachers UNIVERSITY OF MONTANA 1971 Approved by: Chairman, Board of Examiners De^ , Graduate *School / n ? / Date Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. UMI Number: EP39098 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. UMT DiMMtstion PuWiahing UMI EP39098 Published by ProQuest LLC (2013). Copyright in the Dissertation held by the Author. -
CF 7.4 V2.Indd
2007 VOLUME 7 NUMBER 4 Product Directory Grignard and Organozinc Reagents RIEKE® HIGHLY REACTIVE METALS GRIGNARD REAGENTS ORGANOZINC HALIDES DIALKYLMAGNESIUM AND DIALKYZINC REAGENTS 2-Pyridylzinc bromide: a shelf-stable 2-pyridyl anion equivalent; an important motif in many pharmacologically active molecules. sigma-aldrich.com 2 Table of Contents Sigma-Aldrich is committed to providing the most extensive portfolio of high-quality Grignard, organozinc, and other organometallic reagents, and we continually expand our product listing. Within each section of this directory, products are listed by increasing carbon content. Rieke® Highly Reactive Metals If viewing the electronic version simply select Grignard Reagents a category to jump to that section or activate Alkyl Alkenyl Alkynyl Aryl Heteroaryl your Adobe Bookmarks. You may also search by name, product number, molecular formula, Organozinc Halides or CAS registry number simply by using the “find” feature in Adobe (Ctrl+F in Windows or Alkyl Alkenyl Aryl Heteroaryl Introduction Command+F in a Mac environment). Dialkylmagnesium and Dialkylzinc Reagents If you are unable to find a reagent for your research “Please Bother Us” at [email protected], or contact your local Sigma-Aldrich office (see back cover). Foreword Reuben D. Rieke President and CEO, Rieke Metals, Inc. Professor Emeritus, University of Nebraska Lincoln, NE In the last 35 years, considerable research has been done in the area of generating reactive metals that can be used to synthesize novel organometallic reagents. In 1972, we reported a general approach for preparing highly reactive metal powders, relying on the reduction of metal salts with alkali metals in ethereal or hydrocarbon solvents. -
Experiment 12 Grignard Reaction; Preparation of Triphenylcarbinol
Experiment 12 Grignard Reaction; Preparation of Triphenylcarbinol In this experiment we will perform a Grignard addition to an ester. First we will form the Grignard reagent from magnesium and bromobenzene and then we will add it to methyl benzoate to produce triphenylcarbinol (also called triphenylmethanol). The overall sequence is shown in Figure 12.1 and the mechanism for the addition is shown in Figure 12.2. Figure 12.1 Grignard Addition to Methyl benzoate Br MgBr + Mg THF warm bromobenzene phenylmagnesium bromide O OMgBr OH C MgBr C C HCl OCH + MgBr(OH) 2 + 3 H2O methyl benzoate Triphenylcarbinol Since we are using an ester as our electrophile in this reaction, the nucleophilic Grignard reagent, prepared from the bromobenzene and magnesium, will add to the carbonyl two times to give the triphenyl adduct that on treatment with aqueous acid gives the free alcohol. Note that we have a ketone intermediate. This is even more reactive than the starting ester (why?) and reacts again with the Grignard reagent. Figure 12.2 Mechanism for Grignard Addition MgBr+ O O O OCH3 C C BrMg C OCH + -OCH 3 + 3 MgBr OH OMgBr HCl MgBr(OH) + C C H2O Physical Constants Compound Mol. Wt (g/mol) Density b.p. (°C) m.p. (°C) (g/mL) Bromobenzene 157.02 1.491 156 -31 Methyl benzoate 136.15 1.094 198-199 -12 Magnesium 24.31 1.740 - 648 Triphenylcarbinol 260.34 solid 360 160-163 Tetrahydrofuran (THF) 72.11 0.889 65-67 -108 Procedure: The set-up for this experiment is shown in Figure 12.3. -
University Microfilms, Inc., Ann Arbor, Michigan MONOMERIC ORGANOSILICON COMPOUNDS
This dissertation has been . micro&hned exactly as received 66-3860 CHAPMAN, Dwain R, 1929- MONOMERIC ORGANOSnJCON COMPOUNDS WITH POLYFUNCTIONAL GROUPS. Iowa State University of Science and Technology Ph.D., 1965 Chemistry, organic University Microfilms, Inc., Ann Arbor, Michigan MONOMERIC ORGANOSILICON COMPOUNDS . WITH POLYPUNCTIONAL GROUPS by Dwain R Chapman A Dissertation Submitted to the Graduate Faculty in Partial Fulfillment of The Requirements for the Degree of DOCTOR OF PHILOSOPHY Major Subject: Organic Chemistry Approved Signature was redacted for privacy. In Chai^ge of Major Work Signature was redacted for privacy. Head of Major Department Signature was redacted for privacy. Iowa State University Of Science and Technology Ames, Iowa 1965 11 TABLE OP CONTENTS' Page INTRODUCTION , 1 NOMENCLATURE 3• HISTORICAL 5 Cyclosilanes 5 Reactions of Cyclosilanes 6 Reactions of the Silicon-Silicon Bond 12 The Ultraviolet Absorption Properties 21 of Polysilanes Heterocyclic Polysilanes 23 . EXPERIMENTAL 28 Preparation of Cyclosilanes 30 Octaphenylcyclotetrasilane. 30 Decaphenylcyclopentasilane (Ila) 31 Dodecamethylcyclohexasilane 32 % Reactions of Octaphenylcyclotetrasilane 33 Octaphenylcyclotetrasilane with 33 , . phosphorus pentachloride In benzene 33 Tn xylene 33 Octaphenylcyclotetrasilane with 34 phosphorus trichloride (attempted). Octaphenylcyclotetrasilane with . 34 chlorine In carbon tetrachloride 34 In ether 34 In petroleum ether (b.p. 60-70 C) 36 In n-pentane 36 In ether containing hydroquinone ' 36 Ill Octaphenylcyclotetrasllane -
Burning Magnesium, a Sparkle in Acute Inflammation: Gleams from Experimental Models
Journal Identification = MRH Article Identification = 0418 Date: April 6, 2017 Time: 1:32 pm Magnesium Research 2017; 30 (1): 8-15 REVIEW Burning magnesium, a sparkle in acute inflammation: gleams from experimental models Sara Castiglioni, Alessandra Cazzaniga, Laura Locatelli, Jeanette AM Maier Dipartimento di Scienze Biomediche e Cliniche L. Sacco, Università di Milano, Milano, I-20157, Italy Correspondence: Dipartimento di Scienze Biomediche e Cliniche Luigi Sacco, Università di Milano, Via GB Grassi, 74 Milano 20157, Italy <[email protected]> Abstract. Magnesium contributes to the regulation of inflammatory responses. Here, we focus on the role of magnesium in acute inflammation. Although present knowledge is incomplete to delineate an accurate scenario and a sche- dule of the events occurring under magnesium deficiency, it emerges that low magnesium status favors the induction of acute inflammation by sensitizing sen- tinel cells to the noxious agent, and then by participating to the orchestration of the vascular and cellular events that characterize the process. Key words: magnesium, acute inflammation, leukocytes, endothelial cells Inflammation has been observed since the pathological processes, including the regulation of beginning of documented medical knowledge [1], immune response [3-7]. TRPM7, which possesses but the disclosure of its significance and com- an ion transport domain and an active kinase plexity is rather recent. It is now clear that domain and is responsible for cellular Mg homeo- inflammation is the automatic response of living stasis, phosphorylates phospholipase C␥2, crucial tissues to damage. Through a series of inter- in intracellular signaling after the activation of connected events involving blood vessels and B lymphocytes, and is implicated in T cell migra- leukocytes, it defends from damages and paves the tion [7, 8]. -
Nucl Ear Magnetic Resonance Spectroscopy. the Configurational Stability of Primary Grignard Reagents. Structure and Medium Effec
// lRepriatcd froo thc Jourad of tbc Aocrtc-' Chonicd Socicty, t?, {878 (1965).1 Nuclear MagneticResonance Spectroscopy. The ConfigurationalStability of Primary GrignardReagents. Structure and Medium Effects GeorgeM. Whitesidesand John D. Roberts IReprinted from the Journal of the American ChemicalSociety, 87,'1873 (196.j).I Copyright l9ti;i by the American Chemical Society and reprinted by permissionof the copyright owner NuclearMagnetic Resonance Spectroscopy. The ConfigurationalStability of Primary Gri-snard Reasents. Structureand Medium Effects' GeorgeM. Whitesidesand John D. Roberts Contribution lVo.3172 from the Gutes and Crellin Laboratories of Chemistry, Culifornia Instituteof Technology,Pasadena, CuliJ'orniu. ReceivedJanuarv 9, 1965 Qualitative and semiquontitative examination of the This observationsuggests that careful examination of lemperaturedependence of the RCH,:-Mg proton n.m.r. the spectrum oi this and related compounds in dif- spectra of several Grignard reagents indicates that the ferent solventsand at different concentrationsmight rate of inversiortat this center is relativel-v*insensitive to provide data pertinent to the mechanismof this in- the structurc of the group R. Secondar),Grignard re- version and to the nature o[ Grignard reagentsin ugentsinvert much more slowlv, if at all. The dependence solution. of the inversion rate of the primary orgonometallic Much of the modern work concernedwith the struc- compoundson solventcharacter and on added salts sug- ture of Grignard reagents has centered around at- gests that inversionproceeds br means of a mcchunism tempts to evaluate the importance of the so-called having kineric order greater than one. Schlenkequilibrium in describingthe Grignard reagent' In several well-known experiments, Dessy and co- workers examined the exchange reaction between Introduction labeledmagnesium bromide and diethyl-{and diphenyl- The precedingpaper2 presentedn.m.r. -
UNITED STATES PATENT OFFICE 2,677,686 PYRAZINEDERVATIVES and METHO) of PREPARING the SAME Victor K
Patented May 4, 1954 2,677,686 UNITED STATES PATENT OFFICE 2,677,686 PYRAZINEDERVATIVES AND METHO) OF PREPARING THE SAME Victor K. Smith, Jr., Feari River, and Samuel Kushner, Nanuet, N. Y., assignors to American Cyanamid Company, New York, N. Y., a corpo ration of Maine No Drawing. Application 5uly 22, 1952, Serial No. 300,336 8 Claims. (C. 260-250) 2 This invention relates to mono-substituted ous layer is extracted with a solvent, such as di pyrazine. More particularly, it relates to substi ethyl ether. The ether can be concentrated and tuted-2-carbonyl pyrazine. the desired compound crystallized out Or the The role of vitamins in nutrition is well known ether can be removed and the product distilled. i and assumes greater importance as new informa 5, The reaction of the present invention may be tion is made available concerning the particular carried out at a temperature of -10° to 15° C. function of each. Recently it has been found The reaction is complete in from about a few that folic acid was effective in curing macrocytic ininutes up to about tWO hours. anemias and other blood conditions. Also, Com The process of the present invention is de pounds which are folic acid antagonistS, Such as scribed in greater particularity by the following aninopterin, have been found useful in treating specific examples which are given by way of ill abnormal blood conditions such as leukemia. lustration and not limitation. it is well established that nicotinamide is an im Eacample 1 portant, vitamin of the B complex group and its deficiency is the specific cause of pelagira.