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Organometallics in Regio Enantio-Selective Synthes

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Organometallics in Regio Enantio-Selective Synthes THESIS IN JOINT SUPE RVISION DOTTORATO IN SCIENZE CHIMICHE DOCTORAT DE L’UNIVERSITE DE ROUEN SETTORE DISCIPLINARE CHIMICA ORGANICA CHIM/06 Spécialité: CHIMIE XXII CICLO Discipline: CHIMIE ORGANIQUE Organometallics in Regio --- aaandand EnantioEnantio----Selective Synthesis: Structures and Reactivity Gabriella Barozzino Consiglio members of jury Prof. Giovanni POLI (Rapporteur) Université Pierre et Marie Curie (Paris VI) Prof. Paolo VENTURELLO (Rapporteur) Università di Torino Prof. Annie-Claude GAUMONT (Examin er) Université de Caen Prof. Vito CAPRIATI (Examiner) Università di Bari Prof. Hassan OULYADI (Directeur de Thèse à Rouen) Université de Rouen Dr. Alessandro MORDINI (Direttore di Tesi a Firenze) Università di Firenze 2007-2009 INDEX Abbreviations and Acronyms vii Abstracts 1 1. General Introduction 3 1.1. Introduction 3 1.2. Aim of the project 5 1.3. Organolithium chemistry 7 1.3.1. Organolithium structures 7 1.3.2. Organolithium aggregates 8 1.3.3. Dynamic of organolithium compounds 10 1.3.4. Analysis of organolithium compounds 12 First Part 2. Introduction to the Base-Promoted Rearrangement of Strained Heterocycles 15 2.1. Superbases 15 2.1.1. Structures and reactivity 16 2.1.2. Applications 18 2.2. Epoxides and aziridines 20 2.2.1. Epoxides 21 2.2.2. Aziridines 22 2.3. Previous results about the base-induced isomerizations of epoxides 23 2.4. Previous results about the base-induced isomerizations of epoxy ethers 26 2.5. Previous results about the base-induced isomerizations of aziridines 30 2.5.1. Isomerizations of aziridines 31 2.5.2. Elaboration of allylic amines 34 i Index 3. Rearrangements of Aziridinyl Ethers Mediated by Superbases 37 3.1. Introduction 37 3.2. Synthesis of aziridinyl ethers 37 3.2.1. Synthesis of (2S,3R)-2-[(tert-butyldiphenylsilyl)oxy]methyl-3- (methoxy-methoxy)methyl-N-(para-toluen-sulfonyl -aziridine 100 38 3.2.2. Synthesis of derivatives of the aziridine 100 39 3.2.3. (2R,3S)-2-methylether-3-iso-propyl-N-(para-toluensulfonyl)- aziridines 114 41 3.3. Isomerization of aziridinyl ethers 43 3.3.1. β-Elimination 43 3.3.2. 4-exo Intramolecular cyclization 45 4. Base-Induced Rearrangements of Epoxides and Aziridines Mediated by Microwaves 57 4.1. Introduction 57 4.1.1. Aim of the study 57 4.1.2. Microwave Theory 58 4.2. Synthesis of the substrates 60 4.2.1. Synthesis of epoxides 60 4.2.1. Synthesis of aziridines 60 4.3. MWs mediated base-promoted isomerizations of strained heterocycles 62 4.3.1. Isomerization of epoxides 62 4.3.2. Isomerization of aziridines 67 5. Synthesis of a New Family of 2-Ethylidene-γ-Unsaturated δ-Amino Ester via Microwave Activated Stille Coupling 71 5.1. Introduction 71 5.1.1. Peptidomimetics and Isosters 71 5.1.2. Aim of the project 72 5.2. Results and discussion 74 5.2.1. Synthesis of substrates 74 5.2.2. Stille Coupling with (E)-methyl-2-bromobutenoate 2a : synthesis of δ-aminoesters 3a 77 5.2.3. Stille Coupling with (E)-methyl-2-bromobutenoate 2a : synthesis of 1-substituted butenoates 187-189 79 5.2.4. Stille Coupling with (E)-methyl-2-bromobutenoate 2a : synthesis of 2-ethylidene-γ-unsaturated δ-amido ester 207 79 ii Index 5.2.5. Synthesis of the dipeptide 208 80 6. Enantioselective Base-Promoted Isomerization of Epoxides into Allylic Alcohols 83 6.1. Introduction 83 6.1.1. Previous studies about enantioselective isomerization of epoxides 83 6.1.2. Previous studies about enantioselective applications of 3- APLi’s as chiral ligands 87 6.1.3. Aim of the study 94 6.2. Results and discussion 95 6.2.1. Synthesis of 3-aminopyrrolidines 95 6.2.2. Enantioselective isomerizations of meso-epoxides to allylic alcohols with 3-APLis as bases 97 6.2.3. Enantioselective isomerizations of meso-cyclohexene oxide to cyclohexen-2-ol with 3-APLis as chiral ligands of organolithium compounds 103 6.2.4. Enantioselective isomerizations of meso-cyclohexene oxide to cyclohexen-2-ol with 3-APLis as superbasic mixture with potassium tert-butoxide 105 7. Conclusions of the first part 109 7.1. Results 109 7.1. Perspectives 112 Second Part 8. Introduction to the second part 117 8.1. Chiral phosphines and chiral phosphine boranes 117 8.2. Aim of the project 120 8.3. General considerations about the NMR techniques applied to organolithium derivatives 123 8.4. Presentation and order of the NMR sequences carried out for our study 127 8.5. Structural NMR studies of lithiated phosphides 129 iii Index 9. Results Obtained 133 9.1. Structure in THF solution of model Ph 2P(BH 3)Li 133 9.1.1. Synthesis of the starting materials and their NMR descriptions 133 9.1.2. Synthesis of lithium diphenylphosphide borane and NMR analyses 140 9.1.3. Theoretical view of the lithium diphenylphosphine borane structure 155 9.2. NMR analyses of 1 : 1 Ph 2P(BH 3)Li / RLi mixtures (R = n-Bu, DA) 159 9.2.1. RLi = n-BuLi 159 9.2.2. RLi = LiDA 167 10. Reductions of Carbonyl Species with Lithium Phosphides 173 10.1. Results in synthesis 173 10.2. Structural NMR investigation: results obtained 175 10.3. Extension of the reaction to other substrates: ketones 180 10.4. Reduction with other secondary phosphine boranes 181 11. Conclusions of the second part 185 11.1. Results 185 11.1. Perspectives 189 Third Part 12. Experimental Part 193 12.1. Experimental Details 193 12.2. Titration of organolithium compounds 201 12.3. Synthesis of epoxides 203 12.4. Synthesis of aziridines 205 12.4.1. Synthesis of meso-aziridines by nitrene transfer on a double C=C bond 205 12.4.2. Synthesis of meso-N-protect-aziridines from cyclohexene oxide 209 12.5. Synthesis of aziridinyl ethers 213 iv Index 12.5.1. Synthesis of (2S,3R)-2-[(tert-butyldiphenylsilyl)oxy]-methyl- 3-(methoxymethoxy)methyl-N-(para-toluen-sulfonyl)- aziridine 100 and its derivatives 213 12.5.2. Synthesis of 2-methylether-3-isopropyl-N-(para- toluensulfonyl)-aziridines 224 12.6. Synthesis of chiral lithium amides 241 12.6.1. Synthesis of chiral aminopyrrolidines from 1-benzyl-3- aminopyrrolidine 241 12.6.2. Synthesis of chiral aminopyrrolidines from trans-4-hydroxy- (L)-proline 248 12.7. Base-promoted isomerization of epoxides 256 12.7.1. Isomerizations with LDA 256 12.7.2. Isomerizations with superbases 265 12.7.3. Isomerizations with 3-APLi’s 266 12.8. Base-promoted isomerization of aziridines and aziridinyl ethers 274 12.8.1. Isomerizations with LDA 274 12.8.2. Isomerizations with superbases 281 12.8.3. Isomerizations with BuLi / PMDTA 292 12.9. Synthesis of a new family of 2-ethylidene-γ-unsaturated δ-amino esters via microwave activated Stille coupling 299 12.9.1. Synthesis of γ-stannylamines 299 12.9.2. Stille Coupling reaction 313 12.9.3. Synthesis of dipeptides 319 12.10. Synthesis of [ 6Li] organolithium compounds 323 12.11. Synthesis of phosphines 324 12.11.1. Synthesis of diphenylphosphine borane 10 324 12.11.2. Synthesis of methylphenylphosphine borane 305 326 12.11.3. Synthesis of tert-butylpheylphosphine borane 306 327 12.12. Reduction of carbonyl compounds to alcohols with lithium phosphides 329 12.13. Procedures for NMR experiments 333 13. Bibliography 335 v Index vi ABBREVIATIONS AND ACRONYMS a.a. amino acid 3-AP 3-aminopyrrolidine 3-APLi lithium 3-aminopyrrolidide AcOEt ethyl acetate aq aqueous Bn benzyl Boc tert -butoxycarbonyl (Boc) 2O di-tert -butyl dicarbonate Cp cyclopropyl Cy cyclohexyl Bu n-butyl tBu tert -butyl BuLi n-butyllithium Bus tert -butylsulfonyl D diffusion coefficient DBU 1,8-diazabicyclo[5.4.0]undec-7-ene DCM dichloromethane DEE diethyl ether DEPC diethylcyano-phosphonate DEPT diethylcyanophosphonate (+)-L-DET (+)-diethyl L-tartrate (–)-D-DET (–)-diethyl D-tartrate DIBAL-H di-iso -butylaluminium hydride DIPEA di-iso -propylethylamine DIPA di-iso -propylamine (+)-L-DIPT (+)-di-iso -propyl L-tartrate (–)-D-DIPT (–)-di-iso -propyl D-tartrate DMAP N,N-4-dimethylaminopyridine DME 1,2-dimethoxyethane DMF N,N-dimethylformamide dppp 1,3-bis(diphenylphosphino)propane DMPU N,N’ -dimethylpropyldeneurea e.e. enantiomeric excess eq equation equiv equivalent FW formula weight h hour(s) HMPA hexamethylphosphoramide HSAB Hard and Soft Acids and Bases KO tBu potassium tert -butoxide vii Abbreviations and Acronyms LDA lithium di-iso -propylamide LICKOR n-butyllithium / potassium tert -butoxide LIKNAOR n-butyllithium / sodium tert -butoxide LIDAKOR lithium di-iso -propylamide / potassium tert -butoxide MeLi methyllithium m-CPBA meta -chloroperbenzoic acid MOM methoxymethyl Ms methanesulfonyl m/z mass/charge MW microwave NaHMDS sodium bis(trimethylsilyl)amide NMM N-methyl morpholine NMDO Modified Neglect Diatomic Overlap (S)-(+)-MTPCl (S)-(+)-α-methoxy-α-trifluoromethylphenylacetyl chloride Pd 2(dba) 3 tris(dibenzylideneacetone)dipalladium PMDTA N,N,N’ ,N’ ,N’’ -pentamethyldiethylenetriamine PPTS pyridinium para -toluene sulfonate Py pyridine REDAL-H sodium bis(2-methoxyethoxy(aluminum hydride)) S solvent SAE Sharpless asymmetric epoxidation SKR Sharpless kinetic resolution solv. solvation r.t. room temperature TBAF N,N,N,N-tetra-n-butylammonium fluorine TBDMSCl tert -butylchlorodimethylsilane TBDMSOTf tert -butyldimethylsilyl trifluoromethane sulfonate TBDPSCl tert -butylchlorodiphenylsilane TBHP tert -butyl hydroperoxide TEA N,N,N-triethylamine TFA trifluoroacetic acid THF tetrahydrofuran TMEDA N,N,N’ ,N’ -tetramethylethylenediamine Ts para -toluensulfonyl v volume w weight viii Abbreviations and Acronyms NMR abbreviations COSY COrrelation SpectroscopY DOSY Diffusion Ordered SpectroscopY EXSY Exchange SpectroscopY HMBC Heteronuclear Multiple Bond Correlation HMQC Heteronuclear Multiple Quantum Correlation HOESY Heteronuclear Overhauser Enhancement SpectroscopY NMR Nuclear Magnetic Resonance NOE nuclear Overhauser effect NOESY Nuclear Overhauser Enhancement SpectroscopY PGSE Pulse Gradient Spin-Echo ix ABSTRACTS Résumé Ce travail présente deux études en chimie organométallique (organolithiens). Dans le premier chapitre, des réactions d’isomérisation réalisées en présence de superbases bimétalliques sont impliquées, et la transformation d’aziridines fonctionnalisées est examinée.
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