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Synthesis and Study of New Oxazoline-Based Ligands Mélanie Tilliet KTH Chemical Science and Engineering D octoral Thesis Stockholm 2008 Akademisk avhandling som med tillstånd a v Kungliga Tekniska Högskolan i Stockholm framlägges till offentlig granskning för avläggande av teknologie doktorsexamen i kemi med inriktning mot organisk kemi fredagen den 19e: september kl 10.00 i sal E3, KTH, Osquars Backe 14, Stockholm. Avhandlingen förvaras på engelska. Opponent är D oktor J. H. van Maarseveen, Amsterdam, Nederländerna. 1 ISBN 978-91-7415-093-3 ISSN 1654-1081 TRITA-CHE Report 2008:54 © Mélanie Tilliet 2 Abstract This thesis deals with the study of oxazoline-based ligands in metal-catalyzed asymmetric reactions. The first part describes the synthesis of six new bifunctinal pyridine-bis(oxazoline) ligands and their applications in asymmetric metal-catalysis. These ligands, in addition to a Lewis acid coordination site, are equipped with a Lewis basic part in the 4-position of the oxazoline rings. D ual activation by means of this system was probed in cyanide addition to aldehydes. The second part is concerned with the synthesis of two pyridine-bis(oxazoline) ligands bearing bulky triazole groups in the 4-position of the oxazoline rings and a macrocyclic ligand consisting of a pyridine-bis(oxazoline) moiety and a diaza-18-crown-6 ether. The synthesis of these compounds benefits from the use of “click chemistry”. The ligands thus obtained were tested in different asymmetric catalytic reactions. Complexation studies with different bifunctional molecules that could bind into the cavity of the macrocycle were carried out using NMR spectroscopy. A third chapter is devoted to the synthesis of a supported pyridine-bis(oxazoline) catalyst and its use in catalysis. The pyridine-bis(oxazoline) ligand was efficiently connected to a polystyrene resin via a robust triazole linker. This resin could be employed in different metal- catalyzed asymmetric reactions and good results were obtained in terms of yield and enantioselectivity. Moreover, this polymer-bound ligand could be easily and efficiently recycled. Finally, the last part deals with the use of a hydroxy-containing phosphinooxazoline ligand in the hydrosilylation of imines and in the asymmetric intermolecular Heck reaction. A cationic iridium complex of this ligand was studied by NMR spectroscopy. Keywords: asymmetric catalysis, pyridine-bis(oxazoline), phosphinooxazoline, multifunctional ligand, dual activation, secondary interaction, polymer-supported ligand, “click chemistry”, Lewis acid, Lewis base. 3 Résumé Le sujet de cette thèse est l’étude de ligands comportant un motif bis(oxazoline) pour la catalyse assymétrique organométallique. La première partie décrit la synthèse et les applications en catalyse assymétrique de six nouveaux ligands pyridine-bis(oxazoline). Ces ligands, en plus d’un site de complexation pour un acide de Lewis, possèdent des fonctions basiques en position 4 des cycles oxazoliniques. U ne double activation au moyen de ces catalyseurs a été testée pour l’addition de cyanures au benzaldéhyde. La deuxième partie concerne la synthèse de deux ligands pyridine-bis(oxazoline) présentant des groupement encombrés en position 4 des oxazolines et celle d’un macrocycle composé d’une partie pyridine-bis(oxazoline) et d’un diaza éther couronne. La synthèse de ces trois nouveaux ligands emploie avec profit la « click chemistry ». Ces ligands ont été évalués en catalyse assymétrique. La structure de complexes du macrocycle avec differentes molecules bifonctionelles a également été étudiée en RMN. Le troisième chapitre a pour sujet la synthèse et l’utilisation en catalyse assymétrique organométallique d’un nouveau ligand supporté à motif pyridine-bis(oxazoline). Le ligand a été connecté de façon efficace sur une résine polymère via un groupement triazole robuste. Cette résine a été employée en combinaison avec différents métaux pour catalyser plusieurs réactions catalytiques assymétriques. D e plus, le ligand supporté a pu être recyclé facilement un grand nombre de fois. Enfin, la dernière partie traite de l’utilisation d’un ligand phosphinooxazoline possèdant une fonction hydroxy liée à l’oxazoline, pour l’hydrosylilation d’imines et la réaction de Heck intermoléculaire assymétrique. U n complexe cationique d’iridium et de ce liagnd a été étudié en RMN. M ots-clés : catalyse assymétrique, pyridine-bis(oxazoline), phosphinooxazoline, ligand multifunctionel, double activation, interaction secondaire, ligand supporté sur polymère, “click chemistry”, acide de Lewis, base de Lewis. 4 List of publications This thesis is based on the following papers gathered at the end of this document: I. Polym er-Bound Pyridine-Bis(oxazoline). Preparation through C lick C hem istry and Evaluation in A sym m etric C atalysis. Mélanie Tilliet, Stina Lundgren, Christina Moberg and V incent Levacher. Adv. Synth. Catal. 2007, 349, 2079. II. C onvenient Preparation of Bifunctional Pybox Ligands. Mélanie Tilliet, Anders Frölander, V incent Levacher and Christina Moberg. Tetrahedron, accepted. III. Influence of Ligand Secondary Interactions on D ynam ic Processes in A lkene Iridium C om plexes. Mélanie Tilliet, Anders Frölander, Krister Z etteberg, Z oltan Szabo and Christina Moberg. Prelim inary m anuscript. IV . Evaluation of new pyridine-bis(oxazoline) ligands in asym m etric catalysis. Mélanie Tilliet, Anders Frölander, Stina Lundgren, V incent Levacher and Christina Moberg. Prelim inary m anuscript. 5 Abbreviations and Acronymes Å Ångström Abs conf absolute configuration Ac acetyl AMP adenosine monophosphate BINAP 2,2'-bis(diphenylphosphino)-1,1'-binaphthyl BINOL 1,1’-bi-2-naphtol °C degrees Celsius Bn benzyl box bis(oxazoline) COD 1,5-cyclooctadiene Conv conversion D IEA diisopropylethylamine D IOP ((4S,5S)-2,2-dimethyl-1,3-dioxolane-4,5- diyl)bis(methylene)bis(diphenylphosphine) D MAP 4-(N,N-dimethylamino)pyridine D MF dimethylformamide D MSO dimethylsulfoxide ED C-HCl 1-ethyl-3-(3’-dimethylaminopropyl)carbodiimide monohydrochloride ee enantiomeric excess equiv equivalent EX SY exchange spectroscopy FG functional group GC gas chromatography HOBt 1-hydroxybenzotriazole HPLC high performance liquid chromatography i-Pr isopropyl IR infrared LG leaving group Ms mesylate MS mass spectrometry MT magnetization transfer NBD norbornadiene NMM N-methylmorpholine NMR nuclear magnetic resonance NOESY nuclear Overhauser effect spectroscopy Nu nucleophile PEG polyethylene glycol 6 Oh phenyl PHOX phosphinooxazoline PS polystyrene p-Tol para-tolyl pybox pyridine-bis(oxazoline) rt room temperature s-Bu sec-butyl TASF tris(dimethylamino)sulphonium difluoromethylsiliconate TBAF tetrabutylammonium fluoride t-Bu tert-butyl Tr trityl Tf triflate THF tetrahydrofuran TMSA trimethylsilyl acetylene TMSAN (trimethylsilyl)acetonitrile TMSCN trimethylsilyl cyanide Ts tosyl U V ultraviolet 7 8 Table of contents 1) Introduction a. Oxazoline based-ligands in metal-catalyzed asymmetric reactions b. Aim of this thesis 2) New bifunctional pyridine-bis(oxazoline) ligands a. Multifunctional catalysts b. Ligands synthesis c. Catalytic asymmetric addition of cyanides to benzaldehyde d. Conclusion and perspectives 3) New “click” pyridine-bis(oxazoline) ligands a. Background i. Crown ethers ii. Macrocycles and receptors containing a crown ether moiety b. Ligands synthesis c. Complexation studies d. Catalysis i. Asymmetric Mukaiyama aldol reaction ii. Addition of (trimethylsilyl)acetonitrile to benzaldehyde e. Conclusion and perspectives 4) New polymer-supported pyridine-bis(oxazoline) ligand a. Supported ligands b. Ligand synthesis c. Catalysis i. TMSCN epoxide opening ii. Silylcyanation of benzaldehyde iii. Alkynylation of imines d. Conclusion and perspectives 5) Hydroxy-containing phosphinooxazoline ligand a. Phosphinooxazoline ligands b. Catalysis i. Asymmetric hydrosilylation of imines ii. Asymmetric intermolecular Heck reaction c. NMR studies d. Conclusion and perspectives 6) Concluding remarks and outlook 7) Acknowledgements 8) Experimental section 9) References 9 10 1) Introduction a. Oxazoline-based ligands in metal-catalyzed asymmetric reactions Oxazolines are five-membered cyclic iminoesters. They were first synthesized more than hundred and twenty years ago.1 At the beginning they were widely used in organic synthesis, in particular as masked carboxylic acids.2 The first example of a chiral oxazoline ligand was reported in 1986 by Brunner and co-workers.3 Since then, a very large number of chiral ligands containing one, or more, oxazoline rings have been synthesized and applied to a wide range of metal- catalyzed asymmetric transformations.4 These compounds are usually obtained in a few steps from readily available amino alcohols. Most of them have a stereogenic center at the carbon atom adjacent to the coordinating nitrogen. As a consequence, the active metal site is held in close proximity to the chiral center, which can directly influence the stereochemistry of the reaction. Chirality can also be introduced in other positions, for example at the carbon atom adjacent to the oxygen or at one of the substituents. The structure of oxazoline-based ligands can be easily tuned for a specific reaction (scheme 1). Chiral substituent *R NH2 O ∗ ∗ HO ∗ R'' R' N ∗ R'' R' Chiral centers Schem e 1: General feature of oxazoline ligands. Among the chiral oxazoline ligands developed, some incorporate only one oxazoline ring (mono(oxazoline) ligands). Others contain two oxazoline rings (bis(oxazoline) ligands). Finally, tris(oxazoline)
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    Europaisches Patentamt (19) European Patent Office Office europeenpeen des brevets EP 0 674 618 B1 (12) EUROPEAN PATENT SPECIFICATION (45) Date of publication and mention (51) intci.6: C07C 317/32, C07C 233/22, of the grant of the patent: C07C 315/04, C07D 301/19, 09.09.1998 Bulletin 1998/37 C07D 263/14, A61K31/16 (21) Application number: 94903599.2 (86) International application number: PCT/US93/12071 (22) Date of filing: 15.12.1993 (87) International publication number: WO 94/14764 (07.07.1994 Gazette 1994/15) (54) ASYMMETRIC PROCESS FOR PREPARING FLORFENICOL, THIAMPHENICOL, CHLORAMPHENICOL AND OXAZOLINE INTERMEDIATES ASYMMETRISCHES HERSTELLUNGSVERFAHREN FUR FLORFENICOL, THIAMPHENICOL, CHLORAMPHENICOL UND OXAZOLIN-ZWISCHENPRODUKTE PROCEDE ASYMETRIQUE DE PREPARATION DE FLORFENICOL, THIAMPHENICOL, CHLORAMPHENICOL ET D'INTERMEDI AIRES OXAZOLINE (84) Designated Contracting States: (74) Representative: AT BE CH DE DK ES FR GB GR IE IT LI LU NL PT von Kreisler, Alek, Dipl.-Chem. et al SE Patentanwalte, von Kreisler-Selting-Werner, (30) Priority: 18.12.1992 US 993932 Bahnhofsvorplatz 1 (Deichmannhaus) 50667 Koln (DE) (43) Date of publication of application: 04.10.1995 Bulletin 1995/40 (56) References cited: EP-A- 0 423 705 EP-A- 0 472 790 (73) Proprietor: SCHERING CORPORATION WO-A-92/07824 US-A- 4 235 892 Kenilworth New Jersey 07033 (US) US-A- 4 876 352 US-A- 4 900 847 (72) Inventors: • CHEMICAL ABSTRACTS, vol. 107, no. 1, 06 July • WU, Guang-Zhong 1987, Columbus, Ohio, US; abstract no. 6859M, Somerville, NJ 08876 (US) JOMMI, GIANCARLO ET AL '2-Oxazolidinones • TORMOS, Wanda, I. as regioselective protection of beta-amino Elizabeth, NJ 07202 (US) alcohols in the synthesis of 2-amino-1-aryl-3-fluoro-1-propanols' page 632; column 1; & GAZZ.
  • Selective Catalysis by Polymer-Supported Ruthenium

    Selective Catalysis by Polymer-Supported Ruthenium

    Brigham Young University BYU ScholarsArchive All Theses and Dissertations 2019-03-01 Selective Catalysis by Polymer-Supported Ruthenium NanoparticlesAND New Ligand Design for Cooperative and Bimetallic Catalysis Seyed Hadi Nazari Brigham Young University Follow this and additional works at: https://scholarsarchive.byu.edu/etd BYU ScholarsArchive Citation Nazari, Seyed Hadi, "Selective Catalysis by Polymer-Supported Ruthenium NanoparticlesAND New Ligand Design for Cooperative and Bimetallic Catalysis" (2019). All Theses and Dissertations. 7386. https://scholarsarchive.byu.edu/etd/7386 This Dissertation is brought to you for free and open access by BYU ScholarsArchive. It has been accepted for inclusion in All Theses and Dissertations by an authorized administrator of BYU ScholarsArchive. For more information, please contact [email protected], [email protected]. Selective Catalysis by Polymer-Supported Ruthenium Nanoparticles AND New Ligand Design for Cooperative and Bimetallic Catalysis Seyed Hadi Nazari A dissertation submitted to the faculty of Brigham Young University in partial fulfillment of the requirements for the degree of Doctor of Philosophy David J. Michaelis, Chair Steven L. Castle Joshua L. Price Daniel H. Ess Roger G. Harrison Department of Chemistry and Biochemistry Brigham Young University Copyright © 2019 Seyed Hadi Nazari All Rights Reserved ABSTRACT Selective Catalysis by Polymer-Supported Ruthenium Nanoparticles AND New Ligand Design for Cooperative and Bimetallic Catalysis Seyed Hadi Nazari Department of Chemistry and Biochemistry, BYU Doctor of Philosophy The abstract is the summary of three different projects all centered around the general idea of catalysis which is the general theme of research in the Michaelis laboratory. The first project focuses on development of a new heterogeneous catalyst for selective catalysis.