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The First Anionic Thia-Fries Rearrangement at Arene Tricarbonylchromium Complexes and Reactions of Phthalimide Tricarbonylchromium Complexes

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The First Anionic Thia-Fries Rearrangement at Arene Tricarbonylchromium Complexes and Reactions of Phthalimide Tricarbonylchromium Complexes The First Anionic Thia-Fries Rearrangement at Arene Tricarbonylchromium Complexes and Reactions of Phthalimide Tricarbonylchromium Complexes Der Naturwissenschaftlichen Fakultät der Gottfried Wilhelm Leibniz Universität Hannover zur Erlangung des Grades einer Doktorin der Naturwissenschaften Dr. rer. nat. genehmigte Dissertation von M. Sc. Zhirong Zhao-Karger geboren am 01.11.1970 in Damaolianhe Banner, China 2006 Referent: Prof. Dr. Holger Butenschön Koreferent: Prof. Dr. Helmut Duddeck Tag der Promotion: 15.12.2006 Abstract The First Anionic Thia-Fries Rearrangement at Arene Tricarbonylchromium Complexes and Reactions of Phthalimide Tricarbonylchromium Complexes Two topics concerning the chemistry of arene tricarbonylchromium complexes with functionalized anellated ring are involved i.e. generation of an η6-aryne tricarbonylchromium(0) complex and the exploration of the anion accelerated reactions of N-substituted phthalimide complex. Some moderately air-stable aryl triflate tricarbonylchromium complexes have been prepared from the corresponding phenols and attempted to generate aryne tricarbonylchromium complexes by triflic acid elimination. Unanticipated ortho sulfone substituted phenol complexes were obtained in high yield as a result of an anionic thia-Fries rearrangement of the arene chromium tricarbonyl triflate complexes upon treatment with LDA or BuLi at –78 °C. Double anionic thia-Fries rearrangement of tricarbonyl(1,4-dihydroxylbenzene)chromium(0) bis(triflate) has been achieved by using LDA as base. Asymmetric deprotonation using an enantiomerically pure chiral lithium amide base has been applied to the anionic thia-Fries rearrangement of the tricarbonylchromium phenyl triflate complex to afford the corresponding enantiomerically enriched planar chiral 2-sulfonylphenol complex. The new anionic thia-Fries rearrangement of tricarbonyl(phenyltriflate)chromium complexes has been applied to the tricarbonylchromium complex of estrone, providing a new 2- trifluoromethylsulfonyl substituted steroid. An unusual endo-adduct obtained in the nucleophilic adddition of 1-propynyllithium to N-vinylphthalimide tricarbonylchromium complex provides evidence for the intermadiacy of a planar chiral acylimium ion. The synthetic application of planar chiral tricarbonylchromium complex of N-acyliminium ion has been preliminarily investigated. (η6-Arene)tricarbonylchromium(0) Complex · Anionic Thia-Fries Rearrangement · Asymmetric Deprotonation · Planar Chiral N-Acyliminium Ion I Kurzfassung Die erste anionische Thia-Fries Umlagerung an (Aren)tricarbonylchrom(0)- Komplexen und Reaktionen der (Phthalimid)tricarbonylchrom(0)-Komplexe Zwei Themen in Bezug auf die Chemie der (Aren)tricarbonylchrom(0)-Komplexen mit funktionalisiertem anelliertem Ring wurden behandelt, nämlich die Erzeugung von (Arin)tricarbonylchrom(0)-Komplexen und die Untersuchung anionisch beschleunigte Reaktionen von N-substituierte (Phthalimid)tricarbonylchrom(0)- Komplexe. Im Rahmen dieser Arbeit wurden zahlreiche mässig luftstabile (Aryltriflat)tricarbonylchrom(0)-Komplexe erstmals aus den entsprechenden Phenolen dargestellt, um durch die Eliminierung von Trifluoromethansulfonsäure (Arin)tricarbonylchrom(0)-Komplexe darzustellen. Unerwarted entstanden ortho Sulfone substituierte Phenol-Komplexe in guter Ausbeute aus einer anionischen thia- Fries-Umlagerung der (Aryltriflat)tricarbonylchrom(0)-Komplexe nach Umsetzung mit LDA oder BuLi bei –78 °C. Die doppelte anionische thia-Fries Umlagerung des Tricarbonyl(1,4-dihydroxylbenzene)-bis(triflate)chrom(0)-Komplexes gelang mit LDA als Base. Zur Synthese von einem enantiomerenreichem planar chiralen 2- sulfonylphenol-Komplexes wurde eine asymmetrische Deprotonierung mit einer chiralen Lithiumamid-Base durchgeführt. Die neue anionische thia-Fries-Umlagerung wurde zur Synthese eines neuen 2-Trifluoromethylsulfonyl substituierten Steroids aus einem Tricarbonylchrom(0)-Komplex der Estrone angewendet. Die Bildung eines ungewöhnlischen endo-Adduktes nach der nucleophilen Addition von 1-Propynyllithium zum N-vinylphthalimid Komplex liefert einen Hinweis ein intermediäre planar chirales Acylimium Ion. Die synthetische Anwendung des planar chiralen Tricarbonylchrom(0)-Komplexes des Acylimium Ions wurde untersucht. (η6-Aren)tricarbonylchrom(0)-Komplex · anionische thia-Fries Umlargung · asymmetrische Deprotonierung · planar chirale N-acyliminium Ion II Meinen Eltern Yining und Stephan III Die experimentellen Ergebnisse dieser Dissertation wurden in der Zeit von November 2002 bis März 2006 am Institut für Organische Chemie der Universität Hannover unter der Leitung von Herrn Prof. Dr. H. Butenschön durchgeführt. Mein besonderer Dank gilt Herrn Prof. Dr. H. Butenschön für die Überlassung des interessanten Themas, die stets freundliche Unterstützung, sowie die gute Betreuung und die vielfältigen Anregungen. Meinen ehemaligen und jetzigen Kollegen Herrn Dr. Markus Schwarz, Herrn Dr. Ingo Weidner, Herrn Dr. Mazhar Hussain, Herrn M. Sc. Nikolai Vinokurov, Frau Dipl.- Chem. Bianka Muschalek, Frau Dipl.-Chem. Karin Kirleis, Herrn Dipl.-Chem. Marc Vollmann, Herrn Dipl.-Chem. Ingma Baumgart gilt mein Dank für die gute Zusammenarbeit, die ständige Hilfsbereitschaft und die interessanten Diskussionen, die zum Gelingen dieser Arbeit beigetragen haben. Herrn Stephan Karger danke ich für das unermüdliche Korrekturlesen dieser Arbeit. Frau A. Kandil danke ich für die Hilfe bei organisatorischen Problemen. Aus der instrumentalanalytischen Abteilung gilt mein Dank Frau D. Körtje, Frau M. Rettstadt, Herrn R. Nöthel und Herrn M. Astratov für die wertvolle Diskussionen und die schnelle Aufnahme der NMR- und Massenspektren. Besonderer Dank gilt Herrn Dr. Wartchow und Herrn Dr. M. Wiebcke vom Instiut für Anorganische Chemie der Universität Hannover für die Anfertigung aller Kristallstrukturanalysen. Bedanken möchte ich mich bei Herrn Prof. Dr. H. Menzel (TU Brauschweig) für die DSC Messung. Nicht vergessen möchte ich, allen Mitgliedern der Arbeitskreise Duddeck, Hoffmann, Winterfeldt, Dräger, Kirschning und Kalesse für ihre Unterstützung zu danken. Der Deutschen Forschungsgemeinschaft (DFG) gilt mein besonderer Dank für die Vergabe einer Stelle als wissenschaftlicher Mitarbeiterin in Rahmen eines DFG- Projekts. Meiner Familie danke ich dafür, dass sie mich immer liebevoll unterstützt hat. IV Abbreviations D [α] rt Specific Rotation Å Angstrom(s) aq. Aqueous APT Attached Proton Test Ar Aryl ATR Attenuated Total Reflection Bn Benzyl br Broad (spectral) Bu Butyl i-Bu iso-Butyl t-Bu tert-Butyl c Concentration °C Degrees Celsius calcd Calculated cat. Catalyst cm−1 Wavenumber(s) 13C NMR 13 C Nuclear Magnetic Resonance δ Chemical Shift mCPBA meta-Chloroperbenzoic acid d Day(s) d Doublet (spectral) dd Doublet of Doublets (spectral) dr Diastereomeric Ratio de Diastereomeric Excess decomp. Decomposition DEE Diethyl Ether DCM Dichlormethan DME Dimethoxymethan DMF dimethylformamide DIPA N,N-diisopropylamine DSC Differential scanning calorimetry V ee Enantiomeric Excess EI Electronic Impact (in mass spectrometry) equiv. Equivalent(s) Et Ethyl FAB Fast Atom Bombardament (in mass spectrometry) FT-ICR Fourier-Transform Ion Cyclotron Resonance FT-IR Fourier-Transform-Infrarot g Gramm GC Gas Chromatography GP General procedure h hour(s) 1H NMR 1H Nuclear Magnetic Resonance HPLC High performance Liquid Chromatography HRMS High resolution Mass Spectrometry Hz Hertz IR Infrarot ISQ In situ quenching J Coupling Constant in NMR Spectrometry L Ligand LDA Lithium diisopropylamide m Multiplet (spectral) M Molar (moles per liter) M+ Parent Molecular Cation (in mass spectrometry) Me Methyl MHz Megahertz mL Milliliter(s) min Minute(s) mmol Millimol MOMCl Methoxyethoxymethyl chloride m.p. Melting Point Me3SiCl trimethylsilylchloride MS Mass Spectrometry MTPA α-Methoxy-α-(trifluoromethyl)-phenylacetic acid MTPA-Cl α-Methoxy-α-(trifluoromethyl)-phenylacetate chloride VI m / z Mass-to-charge Ratio (in mass spectrometry) MW Microwave NMR Nuclear Magnetic Resonance Nu Nucleophile PE Petroleum Ether PG Protecting Group Ph Phenyl ppm Part(s) per Million i-Pr Isopropyl p-TsOH para-Toluene sulfonyl acid q Quartet (spectral) rac Racemic s Singlet (spectral) TBAF Tetrabutylammoniumflouoride TBME tert-Butylmethyl Ether THF Tetrahydrofuran LiTMP Lithium 2,2,6,6-tetramethylpiperidide TMEDA N,N,N',N'-Tetramethylethane-1,2-diamine t Triplet (spectral) TLC. Thin-layer Chromatography TMS Tetramethylsilane TPB 1,3,5-Triphenylbenzene VII Contents A. Introduction......................................................................................................1 B. Results and Discussion...................................................................................14 1. (Aryltriflate)tricarbonylchromium Complexes................................................14 1.1 Attempted Gerneration of Tricarbonylchromium Aryne Complexes..............14 1.2 Synthesis of (Aryltriflate)tricarbonylchromium Complexes ...........................17 1.3 Anionic thia-Fries Rearrangement of Tricarbonylchromium Arene Triflate Complexes........................................................................................................20 1.4 Application of Anionic thia-Fries Rearrangement in Synthesis of 2- Trifluoromethylsulfonyl Estrone (114)............................................................26 1.5 Attempts Towards Double and Triple Anionic Thia-Fries Rearrangemnents.31 1.6 Enantioselective ortho-Deprotonation of Tricarbonyl(phenyltriflate) chromium(0) (93).............................................................................................37
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