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A Focus on Vinyl Selenones
molecules Review ReviewModern Synthetic Strategies with Organoselenium Reagents: Modern Synthetic Strategies with Organoselenium Reagents: AA FocusFocus onon VinylVinyl SelenonesSelenones Martina Palomba, Italo Franco Coelho Dias, Ornelio Rosati and Francesca Marini * Martina Palomba, Italo Franco Coelho Dias, Ornelio Rosati and Francesca Marini * Department of Pharmaceutical Sciences (Group of Catalysis, Synthesis and Organic Green Chemistry), UniversityGroup of Catalysis, of Perugia, Synthesis Via del andLiceo, Organic 06123 GreenPerugia, Chemistry, Italy; [email protected] Department of Pharmaceutical (M.P.); Sciences, italo.francocoelhodias@studeUniversity of Perugia, Via delnti.unipg.it Liceo, 06123 (I.F.C.D.); Perugia, [email protected] Italy; [email protected] (O.R.) (M.P.); *[email protected] Correspondence: [email protected] (I.F.C.D.); [email protected] (O.R.) * Correspondence: [email protected] Abstract: In recent years, vinyl selenones were rediscovered as useful building blocks for new syn- Abstract: In recent years, vinyl selenones were rediscovered as useful building blocks for new thetic transformations. This review will highlight these advances in the field of multiple-bond-form- synthetic transformations. This review will highlight these advances in the field of multiple-bond- ing reactions, one-pot synthesis of carbo- and heterocycles, enantioselective construction of densely forming reactions, one-pot synthesis of carbo- and heterocycles, enantioselective construction of functionalized molecules, and total synthesis of natural products. densely functionalized molecules, and total synthesis of natural products. Keywords: selenium; domino reactions; heterocycles; natural products; spiro compounds; annula- Keywords: selenium; domino reactions; heterocycles; natural products; spiro compounds; annula- tions; enantioselective synthesis; organocatalysis tions; enantioselective synthesis; organocatalysis Citation: Palomba, M.; Dias, I.F.C.; Rosati, O.; Marini, F. -
Contemporary Organosilicon Chemistry
Contemporary organosilicon chemistry Edited by Steve Marsden Generated on 05 October 2021, 02:13 Imprint Beilstein Journal of Organic Chemistry www.bjoc.org ISSN 1860-5397 Email: [email protected] The Beilstein Journal of Organic Chemistry is published by the Beilstein-Institut zur Förderung der Chemischen Wissenschaften. This thematic issue, published in the Beilstein Beilstein-Institut zur Förderung der Journal of Organic Chemistry, is copyright the Chemischen Wissenschaften Beilstein-Institut zur Förderung der Chemischen Trakehner Straße 7–9 Wissenschaften. The copyright of the individual 60487 Frankfurt am Main articles in this document is the property of their Germany respective authors, subject to a Creative www.beilstein-institut.de Commons Attribution (CC-BY) license. Contemporary organosilicon chemistry Steve Marsden Editorial Open Access Address: Beilstein Journal of Organic Chemistry 2007, 3, No. 4. School of Chemistry, University of Leeds, Leeds LS2 9JT, UK doi:10.1186/1860-5397-3-4 Email: Received: 06 February 2007 Steve Marsden - [email protected] Accepted: 08 February 2007 Published: 08 February 2007 © 2007 Marsden; licensee Beilstein-Institut License and terms: see end of document. Abstract Editorial for the Thematic Series on Contemporary Organosilicon Chemistry. The field of organosilicon chemistry has a rich and varied the 1990s, and equivalent to the number appearing in the much history, and has long since made the progression from chemical longer established field of organoboron chemistry -
Herbert Charles Brown, a Biographical Memoir
NATIONAL ACADEMY OF SCIENCES H E R B E R T Ch ARLES BROWN 1 9 1 2 — 2 0 0 4 A Biographical Memoir by E I-I CH I N EGIS HI Any opinions expressed in this memoir are those of the author and do not necessarily reflect the views of the National Academy of Sciences. Biographical Memoir COPYRIGHT 2008 NATIONAL ACADEMY OF SCIENCES WASHINGTON, D.C. Photograph Credit Here. HERBERT CHARLES BROWN May 22, 1912–December 19, 2004 BY EI -ICH I NEGISHI ERBERT CHARLES BROWN, R. B. Wetherill Research Profes- Hsor Emeritus of Purdue University and one of the truly pioneering giants in the field of organic-organometallic chemistry, died of a heart attack on December 19, 2004, at age 92. As it so happened, this author visited him at his home to discuss with him an urgent chemistry-related matter only about 10 hours before his death. For his age he appeared well, showing no sign of his sudden death the next morn- ing. His wife, Sarah Baylen Brown, 89, followed him on May 29, 2005. They were survived by their only child, Charles A. Brown of Hitachi Ltd. and his family. H. C. Brown shared the Nobel Prize in Chemistry in 1979 with G. Wittig of Heidelberg, Germany. Their pioneering explorations of boron chemistry and phosphorus chemistry, respectively, were recognized. Aside from several biochemists, including V. du Vigneaud in 1955, H. C. Brown was only the second American organic chemist to win a Nobel Prize behind R. B. Woodward, in 1965. His several most significant contribu- tions in the area of boron chemistry include (1) codiscovery of sodium borohyride (1972[1], pp. -
MICROREVIEW Reactivity of Polar Organometallic Compounds In
MICROREVIEW Reactivity of Polar Organometallic Compounds in Unconventional Reaction Media: Challenges and Opportunities Joaquin García-Álvarez,*[a] Eva Hevia,*[b] and Vito Capriati*[c] This paper is gratefully dedicated to the memory of Dr. Guy Lavigne Abstract: Developing new green solvents in designing chemical chemicals in chemical transformations is, indeed, solvents used products and processes or successfully employing the already as reaction media, which account for 80–90% of mass utilization existing ones is one of the key subjects in Green Chemistry and is in a typical pharmaceutical/fine chemical operational process. especially important in Organometallic Chemistry, which is an Thus, the solvent itself is often a critical parameter especially in interdisciplinary field. Can we advantageously use unconventional drug product manufacturing and is as well responsible for most reaction media in place of current harsh organic solvents also for waste generated in the chemical industries and laboratories.[3] polar organometallic compounds? This Microreview critically Following these considerations, some of the most critical analyses the state-of-the-art on this topic and showcases recent and intriguing questions that arise are: Can we get traditional developments and breakthroughs which are becoming new research organic solvents out of organometallic reactions?[4] Can we use directions in this field. Because metals cover a vast swath of the protic, recyclable, biodegradable, and cheap unconventional periodic table, the content is organised into three Sections solvents also for highly reactive organometallic compounds? discussing the reactivity of organometallic compounds of s-, p- and Answering these questions would not only mean to break new d-block elements in unconventional solvents. -
Tetrahedron Symposia-In-Print
Tetrahedron 74 (2018) 4875–4878 Tetrahedron Symposia-in-Print Tetrahedron Symposia-in-Print comprise collections of original research papers covering timely areas of organic chemistry. Each symposium is organized by a Symposium Editor who will invite authors, active in the selected field, to submit original articles covering cur- rent research, complete with experimental sections. These papers will be rapidly reviewed and processed for publication by the Symposium Editor under the usual refereeing system. Authors who have not already been invited, and who may have obtained recent significant results in the area of the announced symposium, may also submit contributions for Editorial consideration and possible inclusion. Before submitting such papers authors should send an abstract to the Symposium Editor for preliminary evaluation. Firm deadlines for receipt of papers will allow sufficient time for completion and presentation of ongoing work without loss of the freshness and timeliness of the research results. Symposia-in-Print—already published 1. Recent trends in organic photochemistry, Albert Padwa, Ed. Tetra- 22. Selectivity and synthetic applications of radical reactions, Bernd hedron 1981, 37, 3227–3420. Giese, Ed. Tetrahedron 1985, 41, 3887–4302. 2. New general synthetic methods, E. J. Corey, Ed. Tetrahedron 1981, 23. Recent aspects of organoselenium chemistry, Dennis Liotta, Ed. 37, 3871–4119. Tetrahedron 1985, 41,4727–4890. 3. Recent developments in polycyclopentanoid chemistry, Leo A. 24. Application of newer organometallic reagents to the total Paquette, Ed. Tetrahedron 1981, 37, 4357–4559. synthesis of natural products, Martin Semmelhack, Ed. 4. Biradicals, Josef Michl, Ed. Tetrahedron 1982, 38,733–867. Tetrahedron 1985, 41,5741–5900. 5. -
The Synthesis and Thermochemistry of Organoboron and Phosphorus
The Synthesis and Thermochemistry of Organoboron and Phosphorus Compounds A Thesis submitted by KHAWAJA SABIR HÜ3SAIR in candidature for the degree of Doctor of Philosophy of the University of London Royal Holloway College, Englefleld Green, Surrey. March, 1970. (U.K.;. CLASS N l / V u j AGO. No. I DA ft ACa â u L j j L À ProQuest Number: 10123886 All rights reserved INFORMATION TO ALL USERS The quality of this reproduction is dependent upon the quality of the copy submitted. In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if material had to be removed, a note will indicate the deletion. uest. ProQuest 10123886 Published by ProQuest LLC(2016). Copyright of the Dissertation is held by the Author. All rights reserved. This work is protected against unauthorized copying under Title 17, United States Code. Microform Edition © ProQuest LLC. ProQuest LLC 789 East Eisenhower Parkway P.O. Box 1346 Ann Arbor, Ml 48106-1346 "To all those who wished me to reach this stage" AOKNOlVLEDGmmTS The author wishes to express his gratitude to Dr# Arthur Finch for his Invaluable official supervision and encouragement. He Is highly thankful to Dr. P.J. Gardner for his entire supervision, unfailing encouragement and friendly advice. He Is also thankful to all the academic, technical and clerical staff, of the Chemistry Department, Royal Holloway College, for their co-operation and assistance. He wishes to thank the Petroleum Research Fund for a maintenance grant. ABSTRACT The synthesis and standard heats of formation of some substituted arylboroxlnes are reported. -
Présentation Powerpoint
R-M R-R’ R’-X Cross-Coupling Reactions R-M Functionnalized Organometallic Reagents R-X-R’ R-X-M C-N, C-O and C-S Bond Formation R-B(R’)2 Introduction to Organoboron Chemistry R-Si(R’)3 Introduction to Organosilicon Chemistry Carbometallation Reactions R-M R-R’ R’-X Introduction to Organosilicon Chemistry Generalities R-M Synthesis of Organosilicon Compounds R-X-R’ Hydrosilylation of Unsaturated Systems R-X-M Hiyama Cross-Coupling Hosomi-Sakurai Allylations R-B(R’)2 Brook Rearrangement R-Si(R’)3 Anion-Relay Chemistry (ARC) R-M R-R’ Introduction to Organosilicon Chemistry R’-X Generalities R-M Electronegativity s-Bond strengths (kcal.mol-1) Average Bond Length (Å) Si 1,7 C-C 83 R-X-R’ C-Si 76 C-C 1,54 Si-Si 53 C-Si 1,87 R-X-M H 2,1 C-H 83 C 2,5 Si-H 76 C-O 1,43 R-B(R’)2 Si-O 1,66 Cl 3,0 C-O 86 Si-O 108 N 3,0 R-Si(R’)3 C-N 83 O 3,5 Si-N 76 C-F 116 F 4,0 Si-F 135 R-M R-R’ Introduction to Organosilicon Chemistry R’-X Generalities R-M Electronegativity s-Bond strengths (kcal.mol-1) Average Bond Length (Å) Si 1,7 C-C 83 R-X-R’ C-Si 76 C-C 1,54 Si-Si 53 C-Si 1,87 R-X-M H 2,1 C-H 83 C 2,5 Si-H 76 C-O 1,43 R-B(R’)2 Si-O 1,66 Cl 3,0 C-O 86 Si-O 108 N 3,0 R-Si(R’)3 C-N 83 O 3,5 Si-N 76 C-F 116 F 4,0 Si-F 135 R-M R-R’ Introduction to Organosilicon Chemistry R’-X Generalities R-M Electronegativity s-Bond strengths (kcal.mol-1) Average Bond Length (Å) Si 1,7 C-C 83 R-X-R’ C-Si 76 C-C 1,54 Si-Si 53 C-Si 1,87 R-X-M H 2,1 C-H 83 C 2,5 Si-H 76 C-O 1,43 R-B(R’)2 Si-O 1,66 Cl 3,0 C-O 86 Si-O 108 N 3,0 R-Si(R’)3 C-N 83 O 3,5 Si-N 76 C-F 116 F 4,0 Si-F 135 R-M -
Chemoselective Oxidation of Aryl Organoboron Systems Enabled by Boronic Acid-Selective Phase Cite This: Chem
Chemical Science View Article Online EDGE ARTICLE View Journal | View Issue Chemoselective oxidation of aryl organoboron systems enabled by boronic acid-selective phase Cite this: Chem. Sci.,2017,8,1551 transfer† John J. Molloy,a Thomas A. Clohessy,ab Craig Irving,a Niall A. Anderson,b Guy C. Lloyd-Jonesc and Allan J. B. Watson*a We report the direct chemoselective Brown-type oxidation of aryl organoboron systems containing two oxidizable boron groups. Basic biphasic reaction conditions enable selective formation and phase transfer of a boronic acid trihydroxyboronate in the presence of boronic acid pinacol (BPin) esters, while avoiding speciation equilibria. Spectroscopic investigations validate a base-promoted phase-selective discrimination of organoboron species. This phenomenon is general across a broad range of organoboron compounds and can also be used to invert conventional protecting group strategies, Received 7th September 2016 enabling chemoselective oxidation of BMIDA species over normally more reactive BPin substrates. We Accepted 25th October 2016 Creative Commons Attribution 3.0 Unported Licence. also demonstrate the selective oxidation of diboronic acid systems with chemoselectivity predictable DOI: 10.1039/c6sc04014d a priori. The utility of this method is exemplified through the development of a chemoselective oxidative www.rsc.org/chemicalscience nucleophile coupling. Introduction the broadly similar reactivity prolesofboronicacidsand esters,11 and the added complication of speciation equilibria,11–13 The use of di- and multi-boron containing systems has become establishing chemoselective control within mixed organoboron a powerful approach for the rapid synthesis of highly func- systems represents a signicant challenge. However, the identi- This article is licensed under a tionalized molecules from readily accessible starting mate- cation of new chemoselective control mechanisms would be rials.1,2 Chemoselectivity in these systems is currently achieved a fundamental advance, enabling the design and development of using only two approaches. -
5 -7 -9 -11 Organoselenium Chemistry.' Redox Chemistry Of
J. Am. Chem. SOC.1987, 109, 5549-5551 5549 <- <- 1;1P B solid state or solution above 183K solution below183K Figure 1. Evolution of the (PP3)Rh fragment on going from (PP,)RhH to (PP3)Rh+. within 2 h. The compound 6 in turn adds H2 (1 atm) to reform II 2. Finally, 2 quickly exchanges H, with C2H4to give [(PP3)- Rh(C2H,)](S0,CF,)" (7) whose 31PNMR spectrum with an AB,X spin system closely resembles that of 2. This result is reasonable because of the analogy between the binding of H2 and olefins to metals. It has been previously argued that both steric and electronic factors must be finely "tuned" on a metal fragment to permit the formation of an q2-H2adductla The geometric change of the (PP,)Rh fragment from C,, to C,, symmetry (Figure 1) is ac- companied by a certain variation of the fragmental frontier or- bitals. Likely the key to understand the mechanism of the present cis-dihydride - q2-dihydrogen interconversion may be found in the orbital control operated by the (PP,)Rh fragment. Supplementary Material Available: Analytical data and ex- perimental (80 MHz) and computed 'H NMR spectrum of [(PP,)Rh(HD)] (O,CCF,) (2 pages). Ordering information is given on any current masthead page. (10) The compound, which is a nonconductor in CH3CN and C2HSN02, exists in solution as a 1:l mixture of two isomers most likely due to the triflate ligand (IR 1310 cm-' (s), v (SO) of coordinated triflate). 31P(1HJNMR (CD3COCD,, 298 K) AB2CX system, isomer 1: 6 PA 112.33, 6 PB52.06, 6 Pc 24.70; isomer 2: 6 PA 104.15, 6 PB 52.06, 6 PA 112.33, 6 PB52.06, 6 Pc 2 52 24.70; isomer 2: 6 PA 104.15, 6 PB 52.06, 6 Pc 16.52 (JpApB= 27.0 Hz, JpApC = 14.2 HZ, JpBpc = 34.3 HZ, JpARh = 119.7 HZ, JpB~h= 132.1 HZ, JpC~h =140.9 Hz). -
Synthesis of Organofluorine Compounds and Allenylboronic Acids - Applications Including Fluorine-18 Labelling Denise N
Denise N. Meyer Synthesis of Organofluorine Compounds and Allenylboronic Synthesis of Organofluorine Compounds and Allenylboronic Acids - Applications Including Fluorine-18 Labelling Applications Acids - Allenylboronic Synthesis of Organofluorine Compounds and Acids - Applications Including Fluorine-18 Labelling Denise N. Meyer Denise N. Meyer Raised in Lauterecken, South-West Germany, Denise studied chemistry at Johannes Gutenberg University Mainz where she obtained her Bachelor's and Master's degree. In 2017, she moved to Stockholm where she pursued her doctoral studies with Prof. Kálmán J. Szabó. ISBN 978-91-7911-490-9 Department of Organic Chemistry Doctoral Thesis in Organic Chemistry at Stockholm University, Sweden 2021 Synthesis of Organofluorine Compounds and Allenylboronic Acids - Applications Including Fluorine-18 Labelling Denise N. Meyer Academic dissertation for the Degree of Doctor of Philosophy in Organic Chemistry at Stockholm University to be publicly defended on Friday 4 June 2021 at 10.00 in Magnélisalen, Kemiska övningslaboratoriet, Svante Arrhenius väg 16 B. Abstract This work is focused on two areas: the chemistry of organofluorine and organoboron compounds. In the first chapter, a copper-catalysed synthesis of tri- and tetrasubstituted allenylboronic acids is presented. Extension of the same method leads to allenylboronic esters. The very reactive and moisture-sensitive allenylboronic acids are further applied to the reaction with aldehydes, ketones and imines to form homopropargyl alcohols and amines. In addition, an enantioselective reaction catalysed by a BINOL organocatalyst was developed to form tertiary alcohols with adjacent quaternary carbon stereocenters. The second chapter specialises in the functionalisation of 2,2-difluoro enol silyl ethers with electrophilic reagents under mild reaction conditions. -
Stereoselective Reactions of Organoselenium Compounds
Organoselenium Chemistry Authors: Fateh V. Singh, Thomas Wirth Address: VIT University, Chennai Campus, Vandalur-Kelambakkam Road, Chennai-600127, Tamil Nadu, India Cardiff University, School of Chemistry, Main Building, Park Place, Cardiff CF10 3AT, United Kingdom Email: [email protected] 1 1. Introduction Organoselenium chemistry has been established as valuable research area in synthetic and medicinal chemistry.1-11 After the discovery of the selenoxide elimination reaction in early 1970s,12-14 organoselenium reagents received the great success in organic synthesis including asymmetric synthesis.15-18 More commonly, synthetic transformations such as selenenylations, selenocyclizations and 2,3-sigmatropic rearrangements have been successfully achieved using these reagents under mild reaction conditions.19-33 The application of these reagents in catalysis makes them more suitable reagents in organic synthesis.34-39 Several books,1-7, 41-43 book chapters8-11, 44-48 and review articles49-64 have been published to explain the utility of organoselenium reagents in synthesis. This chapter highlights the application of organoselenium reagents in organic synthesis including asymmetric synthesis. 2. Organoselenium Reagents As Electrophiles Organoselenium reagents play different roles in organic reactions but mainly known for their electrophilic behaviour. The electrophilic selenium species can be generated by the cleavage of the Se-Se bond of diselenides and can be used to activate the olefinic double bonds. Due to their electrophilic character, selenium electrophiles react with olefinic double bonds to form three membered seleniranium ion intermediate. Furthermore, the seleniranium ion intermediate can be employed to achieve various selenenylation reactions with different nucleophiles. 2.1. Selenenylation Reactions 2 Selenium electrophiles have been successfully used to achieve various selenylation reactions such as selenylation of olefins, arenes and other organic species. -
3.3.11 Synthesis of Lysergic Acid Diethylamide by Vollhardt...67
Copyright by Jason Anthony Deck 2007 The Dissertation Committee for Jason Anthony Deck certifies that this is the approved version of the following dissertation: Studies Towards the Total Synthesis of Condylocarpine and Studies Towards the Enantioselective Synthesis of (+)-Methyl Lysergate Committee: Stephen F. Martin, Supervisor Philip D. Magnus Michael J. Krische Richard A. Jones Sean M. Kerwin Studies Towards the Total Synthesis of Condylocarpine and Studies Towards the Enantioselective Synthesis of (+)-Methyl Lysergate by Jason Anthony Deck, B.S.; M.S. Dissertation Presented to the Faculty of the Graduate School of The University of Texas at Austin in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy The University of Texas at Austin May 2007 Studies Towards the Total Synthesis of Condylocarpine and Studies Towards the Enantioselective Synthesis of (+)-Methyl Lysergate Publication No. _______ Jason Anthony Deck, PhD The University of Texas at Austin, 2007 Supervisor: Stephen F. Martin An iminium ion cascade sequence was designed and its implementation attempted to form the pentacyclic core structure of the natural product condylocarpine. Trapping of the transient Pictet-Spengler-type spiroindolenium ion with a latent nucleophile would form two of the five rings of condylocarpine in a regioselective manner. Progress towards the first fully stereocontrolled synthesis of a lysergic acid derivative has been described. The route utilizes intermediates with the appropriate oxidation state for the target, and the two stereocenters are installed via asymmetric catalysis. The d ring and second stereocenter were simultaneously formed via an unprecedented microwave heated asymmetric ring closing metathesis (ARCM). iv Table of Contents List of Figures.....................................................................................................