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Towards New Approaches for the Generation of Phosphorus Based Radical: Synthetic and Mechanistic Investigations

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Towards New Approaches for the Generation of Phosphorus Based Radical: Synthetic and Mechanistic Investigations Towards new approaches for the generation of phosphorus based radical : synthetic and mechanistic investigations Giovanni Fausti To cite this version: Giovanni Fausti. Towards new approaches for the generation of phosphorus based radical : synthetic and mechanistic investigations. Organic chemistry. Normandie Université, 2017. English. NNT : 2017NORMC271. tel-01893162 HAL Id: tel-01893162 https://tel.archives-ouvertes.fr/tel-01893162 Submitted on 11 Oct 2018 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. THÈSE Pour obtenir le diplôme de doctorat Spécialité CHIMIE Préparé au sein de l'Université de Caen Normandie Τοwards new apprοaches fοr the generatiοn οf phοsphοrus based radical : synthetic and mechanistic investigatiοns Présentée et soutenue par Giovanni FAUSTI Thèse soutenue publiquement le 24/07/2017 devant le jury composé de Professeur des universités, UNIVERSITE PARIS 5 UNIVERSITE M. PHILIPPE BELMONT Rapporteur du jury PARIS DESC Maître de conférences HDR, UNIVERSITE TOULOUSE 3 PAUL Mme GHENWA BOUHADIR Rapporteur du jury SABATIER Mme ISABELLE GILLAIZEAU Professeur des universités, UNIVERSITE ORLEANS Président du jury M. SAMI LADHDAR Chargé de recherche, UNIVERSITE CAEN NORMANDIE Membre du jury Mme ANNIE-CLAUDE GAUMONT Professeur des universités, UNIVERSITE CAEN NORMANDIE Directeur de thèse Thèse dirigée par ANNIE-CLAUDE GAUMONT, Laboratoire de chimie moléculaire et thio-organique (Caen) TABLE OF CONTENTS List of tables………………………………………………………………………. 4 List of figures……………………………………………………………………... 5 List of schemes…………………………………………………………………… 7 List of abbreviations………………………………………………………………. 11 Abstract…………………………………………………………………………… 13 Acknowledgements……………………………………………………………….. 14 Chapter 1: General Introduction…………………………………………………... 16 1.1: Phosphorus nomenclature…………………………………………... 16 1.2: Synthesis of organophosphorus compounds………………………... 18 1.3: Markovnikov’s rule…………………………………………………. 19 1.4: Hydrophosphination………………………………………………… 21 1.4.1: Metal-catalyzed hydrophosphination…………………………… 22 1.4.2: Organocatalyzed hydrophosphination…………………………... 25 1.5: Visible light photoredox catalysis………………………………….. 28 1.5.1: Theoretical background…………………………………………. 28 1.5.2: The Jablonski diagram………………………………………… 32 1.5.3: Selected examples of photoredox catalyzed reactions………….. 33 1.5.4: Metal-free photocatalysts………………………………………. 37 1.5.5: Acridinium salt as photocatalyst………..……………………… 38 1.5.6: Eosin Y as photocatalyst………………………………………. 43 1.5.7: Carbon-phosphorus bond forming photocatalyzed 45 reactions…………………………………………………………………………… 1.6: Goal of the thesis…………………………………………………… 54 Chapter 2: Visible light mediated hydrohpsohpinylation reaction……………….. 56 2.1: General context…………..………………………………………… 56 2.2: Anti-Markovnikov alkene functionalizations……………………….. 56 2.2.1: Alkenes as challenging substrates……………………………… 56 2.3: Hydrophosphinylation reaction with phosphinic acid 64 derivatives………………………………………………………………………… 2.3.1: Hypophosphorus derivatives………………………………….. 64 2.3.2: Hydrophosphinylation reaction………………………………… 66 2.3.3: Metal-catalyzed hydrophosphinylation………………………… 67 2.3.4: Triethylborane and radical initiators-assisted 68 hydrophosphinylation…………………………………………………………….. 2.4: Results and discussion………………………………………………. 71 2.4.1: Our photocatalytic approach……………………………………. 71 2.4.2: Optimization studies…………………………………………... 72 2.4.3: Scope and limitations of the hydrophosphinylation 74 reaction…………………………………………………………………………… 2.4.4: Mechanistic studies……………………………………………... 77 2.5: Conclusions………………………………………………………… 86 2.6: Material and methods……………………………………………… 87 2.6.1: General………………………………………………………….. 87 2.6.2: EPR-ST, Fluorescence and Laser Flash Photolysis 88 2 experiments………………………………………………………………………. 2.7: Anti-Markovnikov hydrophosphinylation reaction………………… 89 2.7.1: General procedure……………………………………………… 89 Chapter 3: Generation of Phosphinoyl Radicals through EDA complexes and 103 their Reactivity towards Unactivated Alkenes…………………………………… 3.1: Background………………………………………………………… 103 3.2: Theoretical background for electron-donor acceptor (EDA) 109 complexes…………………………………………………………………………. 3.2.1: General scenario………………………………………………… 109 3.2.2: Photogeneration of radical donor-acceptor (EDA) species and 111 related contributions………………………………………………………………. 3.3: The phosphonoyl radical and hydrophosphinylation reaction……… 115 3.3.1: General overview……………………………………………….. 115 3.4: Results and discussion………………………………………………. 118 3.4.1: Mechanistic investigations……………………………………… 118 3.4.2: Optimization studies…………………………………………… 124 3.4.3: Mechanistic proposal for the photocatalytic approach ………… 127 3.5: Conclusions………………………………………………………… 129 3.6: Material and methods……………………………………………… 130 3.6.1: General………………………………………………………… 130 3.7: Hydrophosphinylation reaction products………………………….. 132 3.7.1: General procedure……………………………………………… 132 Chapter 4: Photocatalyzed Annulation Reaction for the Formation of 143 Phosphorylated Oxindoles………………………………………………………. 4.1: Background……………………………………………………….. 143 4.2: Oxindoles, cyclic isatin derivatives frameworks…………………. 146 4.2.1: Bioactive pharmaceutical compounds………………………… 146 4.2.2: Synthetic pathways to access to C-3 functionalized oxindoles 149 from isatin derivatives……………………………………………………………. 4.2.3: Synthetic pathways to access to C-3 functionalized oxindoles 151 from N-acrylamides………………………………………………………………. 4.2.3.1: Metal-catalyzed annulation reaction……………………. 151 4.2.3.2: Metal-free photoinduced annulation reaction…………… 154 4.3: Results and discussion……………………………………………. 161 4.3.1: Mechanistic studies…………………………………………… 164 4.4: Conclusions……………………………………………………….. 166 4.5: Material and methods……………………………………………… 167 4.5.1: General………………………………………………………… 167 4.6: Annulation reaction to form phosphorylated oxindoles…………… 168 4.6.1: General procedure…………………………………………… 168 General conclusions……………………………………………………………… 179 3 LIST OF TABLES Table 2.1: Identification of the optimal reaction conditions.…………………........… 73 Table 2.2: Scope and limitations of visible light mediated hydrophosphinlyation… 74 Table 3.1: Different meanings of electron-donor (D) and electron-acceptor (A)…….. 111 Table 3.2: Optimization studies for the hydrophosphinylation of alkenes via EDA- 125 complexes activation ………………………………………………………………… Table 3.3: Scope and limitations of hydrophosphinylation reaction………………..... 127 Table 4.1: Identification of the optimal reaction conditions……………………......... 162 Table 4.2: Scope and limitations of the photocatalyzed annulation reaction of N- 164 arylacrylamides with secondary phosphine oxides.…………………………………. 4 LIST OF FIGURES AND CHARTS Figure 1.1: Energy diagram related to the addition of H–X to 21 alkenes.……………………………………………………………………………... Figure 1.2: Proposed transition-state for thiourea-catalyzed hydrophosphination of 27 nitroalkenes.……………………………………………………………………….. Figure 1.3: The solar spectrum.……………………………………………………. 29 Figure 1.4: Graphic illustration of the electron multiplicity of the excited state 30 after light excitation.……………………………………………………………….. Figure 1.5: Common organic and inorganic more common oxidants and their 31 oxidizing capabilities (in MeCN vs. SCE).…………………………………………. Figure 1.6: The Jablonski diagram and possible scenarios with absorption, 32 fluorescence, internal conversion, intersystem crossing and phosphorescence.………………………………………………………………….. Figure 1.7: Most commonly used metal-based photoredox catalysts.…………….... 34 Figure 1.8: The X-ray structure shows the dihedral perpendicular angle between 40 acridinium and mesityl moieties; HOMO and LUMO calculated by DFT method at B3LYP/6-31G (taken from ref. [46]).……………………………………………. Figure 2.1: Hypophosphorus derivatives as versatile substrates for the synthesis of 66 a variety of organophosphorus derivatives…………………………………………. Figure 2.2: Different examples of phosphorylated drugs containing 67 hypophosphorus acid derivatives.………………………………………………….. Figure 2.3: Selected photooxidant for our hydrophosphinylation reaction.…….….. 72 Figure 2.4: 1H-NMR spectrum showed the formation of only anti-Markovnikov or 76 b-adduct……………………………………………………………………………. Figure 2.5: 1H-NMR spectrum showed that traces of a bis-adduct were formed by 77 hydrophosphonylation reaction.………………………………………………...….. Figure 2.6: Different pathways of reactivity between excited state (M*) of a 78 molecule and a quencher (Q)………………………………………………….……. Figure 2.7: Fluorescence spectra (λEx = 430 nm) of acetonitrile solutions of N- 78 methyl-9-mesityl acridinium photocatalyst ([Mes-Acr] = 5 × 10–6 M) containing increasing concentrations of iodonium triflate at 20°C.……………………………. Figure 2.8: Stern-Volmer quenching constant for the reaction of the excited state 79 of Mes-Acr with diphenlyiodonium triflate in MeCN. …………………………… Figure 2.9: Photolysis of acetonitrile solutions of the photocatalyst with 80 diphenyliodonium 73 upon irradiation (LED @ λmax = 420 nm; from t = 0 to 540 s) Figure 2.10: EPR spin-trapping spectra resulting upon irradiation (λ = 420 nm) of 81 a solution of acridinium salt (Mes-Acr) and diphenyliodonium 73 in
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