Abnormal Addition-Elimination (Aea) Mechanism 360, 361
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The Use of Arynes in Organic Synthesis
Dedicated to all those too lazy to visit a library Tetrahedron 59 (2003) 701–730 Tetrahedron report number 629 The use of arynes in organic synthesis He´le`ne Pellissier* and Maurice Santelli Laboratoire de Synthe`se Organique UMR no. 6009, Faculte´ des Sciences de Saint-Je´roˆme, Avenue Esc. Normandie-Niemen, 13397 Marseille, Cedex 20, France Received 27 November 2002 Contents 1. Introduction 701 2. Structure and reactivity 701 3. Generation of arynes 702 4. Pericyclic reactions of arynes 704 4.1. Diels–Alder cycloadditions 704 4.1.1. With cyclic heterodienes 704 4.1.2. With acyclic heterodienes 707 4.1.2.1. Intermolecular cycloadditions 707 4.1.2.2. Intramolecular cycloadditions 709 4.1.3. With other dienes 709 4.2. [2þ2] Cycloadditions 711 4.3. 1,3-Dipolar cycloadditions 712 4.4. 1,4-Dipolar cycloadditions 715 4.5. Ene reactions 715 5. Nucleophilic additions to arynes 717 5.1. Addition of nitrogen nucleophiles 717 5.2. Addition of carbon nucleophiles 718 5.2.1. Lithioacetonitrile derivatives as carbon nucleophiles 718 5.2.2. Lithioenolates as carbon nucleophiles 722 6. Transition metal-catalysed reactions of arynes 723 7. Conclusions 727 1. Introduction arynes. The importance of arynes for the synthesis of natural products particularly alkaloids is well illustrated. The This review is an update of aryne chemistry and covers the term ‘arynes’ will be used to refer both to derivatives literature from 1990–2002 since early work has already of 1,2-dehydrobenzene (benzyne) and their heterocyclic been reviewed extensively.1 The preceding review covered analogues (heteroarynes). -
Mechanistic Studies Into the Reactions of Diazonium And
MECHANISTIC STUDIES INTO THE REACTIONS OF DIAZONIUM AND RELATED COMPOUNDS by CHARLES DOUGLAS MURRAY, B.Sc. Thesis presented for the degree of DOCTOR of PHILOSOPHY University of Edinburgh September 1974 GLBY TO MY PARENTS Douglas William and Isabella Seaton McKenzie Murray • • AND MY BROTHER • • William Graeme Murray I declare that this thesis is my own composition, that the work of which it is a record has been carried.out by myself, and that it has not been submitted in any previcis application for a Higher Degree. The thesis describes results of research carried out • in the Department of Chemistry, University of Edinburgh under the supervision of Professor J. I. G. Cadogan since the 1st October, • 1971, the date of my admission as a research student. The following is a statement of postgraduate courses attended during the last three years: Summer School in Mass Spectrometry, University of Sheffield, 26-30 March 1972; - Recent Developments in the Theory of Concerted Processes, Dr. A. J. Bellamy (five lectures); Organometallic Processes in Organic Chemistry, Professor P. L. Pauson (five lectures); Industrial Research and Development, Dr. B. Gravenor (five lectures); E. U. Chemistry Department Seminars (twenty-five periods). • ACKNOWLEDGEMENTS I should like to express my gratitude to Professor J. I. G. Cadogan for suggesting the topic of research and to Professor Cadogan and Dr. J. T. Sharp for their guidance and encouragement in all aspects of this work. I would also like to record my thanks and appreciation to various other members of Edinburgh University Chemistry Department: to Dr. R. M.Paton for advice and assistance related to e. -
Arynes in Synthesis; New Reaction and Precursor Development
ARYNES IN SYNTHESIS; NEW REACTION AND PRECURSOR DEVELOPMENT A thesis submitted to the University of Manchester for the degree of Doctor of Philosophy in the Faculty of Engineering and Physical Sciences 2014 By Donald McAusland School of Chemistry 2 Contents Abstract 11 Declaration 12 Copyright 13 Acknowledgements 14 1 Introduction 15 1.1 Generationofbenzyne ............................ 17 1.2 Reactionsofbenzyne............................. 19 1.2.1 Pericyclicreactions. 19 1.2.2 Nucleophilicadditiontoarynes . 21 1.2.3 Transition-metal-catalysed reactions . 26 1.3 Selectivitywithsubstitutedarynes . ..... 28 1.4 (Trimethylsilyl)phenyl triflates and related aryne precursors . 32 1.4.1 ortho-Lithiation ........................... 33 1.4.2 [4+2]Cycloaddition . 34 1.4.3 Oxidative para-triflation of acetanilides . 34 1.4.4 Commerciallyavailableprecursors . 35 1.4.5 Precursors for the synthesis of polyaromatic structures...... 35 1.4.6 Other functionalised Kobayashi precursors . ..... 37 1.4.7 Relatedaryneprecursors. 39 1.5 Arynesinsynthesis.............................. 41 1.5.1 Indolesyntheses ........................... 42 2 The Benzyne Fischer Indole Reaction 46 2.1 Introduction.................................. 46 2.1.1 Buchwaldmodification. 47 Contents 3 2.1.2 The arylation of hydrazones with benzyne . 52 2.2 Application of aryne electrophiles to the Fischer indole synthesis . 52 2.2.1 Aryne reactions of other hydrazones . 55 2.2.2 BenzyneFischerindolescope . 58 2.2.3 Substitutedarynes . 60 2.2.4 Miscellaneoustosylhydrazones. 66 2.3 Conclusions .................................. 67 3 Synthesis and Applications of New Aryne Precursors 68 3.1 Introduction.................................. 68 3.1.1 Palladium cross-coupling chemistry . 68 3.1.2 TheSuzukireaction ......................... 69 3.1.3 Organoboronreagents . 71 3.1.4 Chemoselectivity in Suzuki couplings . 74 3.2 Aims..................................... -
Application of the Diels-Alder Reaction
APPLICATION OF THE DIELS-ALDER REACTION TO THE SYNTHESIS OF NATURAL PRODUCT- LIKE LIBRARIES John Reed School of Chemistry Faculty of Science UNSW Australia A thesis submitted in fulfilment of the requirements for the degree of Master of Science in Chemistry January 2017 PLEASE TYPE THE UNIVERSITY OF NEW SOUTH WALES Thesis/Dissertation Sheet Surname or Family name: Reed First name: John Other name/s: Abbreviation for degree as given in the University calendar: MSc School: Chemistry Faculty: Science Title: Application of the Diels-Alder Reaction to the Synthesis of Natural Product-like Libraries Abstract 350 words maximum: (PLEASE TYPE) This thesis is focussed on the use of the diene-regenerative Diels-Alder reaction to assemble bicyclic molecular frameworks that are commonly found in bioactive natural products. Chapter 1 examines the history of natural products in pharmaceuticals, and introduces the concept of natural product derivatisation to improve biological activity. The development of focussed libraries of compounds to discover potent natural product derivatives is contrasted with combinatorial chemistry, using two illustrative case studies. The diene-regenerative Diels-Alder reaction is introduced, and key literature examples of this transformation are discussed. Chapter 2 describes the application of the diene-regenerative Diels-Alder reaction to the synthesis of functionalised 1,2,3,4-tetrahydroisoquinolines bearing aromatic substituents at the C(5)-position. This strategy provides access to a number of compounds that would be difficult to generate using existing methods for 1,2,3,4-tetrahydroisoquinoline synthesis. The diene-regenerative Diels-Alder reaction was tolerant to a broad range of substrates in terms of both sterics and electronic character. -
University of Nevada, Reno the Design and Synthesis of Monomers
University of Nevada, Reno The Design and Synthesis of Monomers for use in Two- Dimensional Polymerizations A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Chemistry by Dustin Day Patterson Dr. Benjamin T. King/Dissertation Advisor August 2017 UNIVERSITY OF NEVADA RENO THEGRADUATE SCHOOL We recommend that the dissertation prepared under our supervision by DUSTIN DAY PATTERSON Entitled The Design And Synthesis Of Monomers For Use in Two-Dimensional Polymerizations be accepted in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Benjamin T. King, Ph.D., Advisor Robert S. Sheridan, Ph.D., Committee Member Christopher S. Jeffrey, Ph.D., Committee Member Lora Richards, Ph.D., Committee Member Glenn Miller, Ph.D., Graduate School Representative David W. Zeh, Ph. D., Dean, Graduate School August 2017 i Abstract The Design and Synthesis of Monomers for Two-Dimensional Polymerizations Dustin Day Patterson Ph.D. Advisor: Professor Benjamin T. King The focus of this dissertation is the design and synthesis of monomers for use in the synthesis of two dimensional polymers (2DPs). 2DPs can be described as laterally connected repeat units which cover a plane with no gaps or overlaps. Monomers used for the synthesis of 2DPs must be designed with at least three reactive functional groups; this permits polymerization into a 2D sheet of repeat units. A total of seven different monomer designs were synthetically sought out. Three of the seven monomers, 1-H, 1-MeO, and 1-F are previously reported and their synthesis was improved upon. Synthesis of three novel monomers, 1-FOH, 1-FPOH, and 1-PZn was attempted with the completion of two of the three targets 1-FOH, 1-PZn and a known derivative, 1-P. -
Synthesis of Polycyclic Aromatic Hydrocarbons: Studies of Aryne Cycloaddition, Acid-Catalyzed Rearrangement, and Coupling Pathways
University of New Hampshire University of New Hampshire Scholars' Repository Master's Theses and Capstones Student Scholarship Winter 2016 SYNTHESIS OF POLYCYCLIC AROMATIC HYDROCARBONS: STUDIES OF ARYNE CYCLOADDITION, ACID-CATALYZED REARRANGEMENT, AND COUPLING PATHWAYS Caitlin Hoffman University of New Hampshire, Durham Follow this and additional works at: https://scholars.unh.edu/thesis Recommended Citation Hoffman, Caitlin, "SYNTHESIS OF POLYCYCLIC AROMATIC HYDROCARBONS: STUDIES OF ARYNE CYCLOADDITION, ACID-CATALYZED REARRANGEMENT, AND COUPLING PATHWAYS" (2016). Master's Theses and Capstones. 1095. https://scholars.unh.edu/thesis/1095 This Thesis is brought to you for free and open access by the Student Scholarship at University of New Hampshire Scholars' Repository. It has been accepted for inclusion in Master's Theses and Capstones by an authorized administrator of University of New Hampshire Scholars' Repository. For more information, please contact [email protected]. SYNTHESIS OF POLYCYCLIC AROMATIC HYDROCARBONS: STUDIES OF ARYNE CYCLOADDITION, ACID-CATALYZED REARRANGEMENT, AND COUPLING PATHWAYS BY CAITLIN L. HOFFMAN B.S., University of New Hampshire, 2012 THESIS Submitted to the University of New Hampshire in Partial Fulfillment of the Requirements for the Degree of Master of Science in Chemistry December 2016 This thesis has been examined and approved in partial fulfillment of the requirements for the degree of a Master of Science in Chemistry by: Thesis Director, Richard P. Johnson, Professor of Chemistry Glen P. Miller, Professor of Chemistry Sterling A. Tomellini, Professor of Chemistry On December 12, 2016 Original approval signatures are on file with the University of New Hampshire Graduate School. ii DEDICATION To my parents, who have supported me from start to finish. -
MICROREVIEW Transition Metal Catalyzed [2+2+2] Cycloaddition and Application in Organic Synthesis
MICROREVIEW Transition Metal Catalyzed [2+2+2] Cycloaddition and Application in Organic Synthesis Sambasivarao Kotha,*[a] Enugurthi Brahmachary,[a] and Kakali Lahiri[a] Keywords: Cyclotrimerization / Heterocycles / Polycycles / Strained molecules / Transition metals The [2+2+2] cycloaddition strategy is complementary to the and of heterocycles. More specifically, syntheses of various well known Diels–Alder reaction for the generation of poly- biologically active molecules, unusual amino acids, and theo- cyclic compounds. This [2+2+2] approach is atom-economical retically interesting molecules are described. An attempt has and, with the availability of new catalysts to effect the also been made to give an overview of recent advances in [2+2+2] cycloaddition reaction, synthesis of a wide variety of the achievement of chemo-, regio-, and stereoselectivity in highly functionalized polycycles is possible. This review de- cyclotrimerization reactions. als with some recent advances relating to [2+2+2] cycload- (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, dition reactions involving the syntheses both of polycycles Germany, 2005) 1. Introduction zation of acetylenes to benzene derivatives reported by Reppe et al. in 1948[1a] accelerated the utility of metal cata- The development of novel reactions, useful reagents, and lysts in this area. Since then, various transition metal cata- efficient catalysts to enable the formation of carbon-carbon lysts based on Ni, Co, Pd, Cr, Rh, Fe, Zr, Nb, Ir, and Ta bonds is an important activity in organic chemistry. More have been developed for the trimerization reaction involving specifically, the use of carbon-carbon bond formation reac- alkynes. Recently, Heiz and co-workers have reported that tions to generate new ring systems is a key part of contem- even a single palladium atom supported on MgO (100) porary organic synthesis. -
This Thesis Has Been Submitted in Fulfilment of the Requirements for a Postgraduate Degree (E.G
This thesis has been submitted in fulfilment of the requirements for a postgraduate degree (e.g. PhD, MPhil, DClinPsychol) at the University of Edinburgh. Please note the following terms and conditions of use: • This work is protected by copyright and other intellectual property rights, which are retained by the thesis author, unless otherwise stated. • A copy can be downloaded for personal non-commercial research or study, without prior permission or charge. • This thesis cannot be reproduced or quoted extensively from without first obtaining permission in writing from the author. • The content must not be changed in any way or sold commercially in any format or medium without the formal permission of the author. • When referring to this work, full bibliographic details including the author, title, awarding institution and date of the thesis must be given. Investigations into Aryne Chemistry Alastair Alexander Cant A thesis submitted in part fulfilment of the requirements of the degree of Doctor of Philosophy Department of Chemistry College of Science and Engineering University of Edinburgh August 2011 Abstract The first project in this thesis describes our research reacting arynes with tertiary allyl amines to generate functionalised anilines via a benzyne induced aza-Claisen reaction. This process works in good to excellent yields and the methodology can be further applied to make benzannulated medium sized ring amine systems. The second project covered in this thesis details our studies in the generation of benzyne from benzoic acid. This process utilises palladium catalysis involving an ortho C-H activation of benzoic acid which generates a 5 membered palladacycle. This palladacycle then spontaneously decomposes with heat to generate palladium bound benzyne and carbon dioxide.