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1
Lavergne, Kaitlyn. "Synthesis of Azomethine Imines via Alkene Aminocarbonylation and their Derivatization into Pyrazolones". Thesis, Université d'Ottawa / University of Ottawa, 2015. http://hdl.handle.net/10393/32516.
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Nitrogen-containing heterocyclic compounds are very important to the pharmaceutical and agrochemical industries, among others. Over the past few years, the Beauchemin group has been exploring reactivity of N-substituted isocyanates and as part of this has developed a metal-free alkene aminocarbonylation process relying on imino-isocyanates to form azomethine imines. The azomethine imines formed are interesting since they contain a cyclic β-aminocarbonyl motif. Catalysis of this reaction using basic additives allowed milder reaction conditions with electron-rich
C=C bonds such as enol ethers. Efforts have also been made towards the derivatization of these azomethine imines into useful products. It was discovered that upon reduction and aromatization of azomethine imines, pyrazolones could be obtained. This is providing a novel modular approach to these compounds, which have relevance in pharmaceuticals and agrochemicals. This reactivity was
extended to include imino-isothiocyanates.
2
Young, Adrian R. "Free radical cyclisation of imines". Thesis, Loughborough University, 1996. https://dspace.lboro.ac.uk/2134/15357.
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Introduction. The free radical cyclisation reaction onto an unsaturated bond is a well known synthetic pathway, where a wide range of cyclic compounds can be produced form acyclic starting materials. Up until recent years, free radical addition to multiple bonds other than carbon-carbon had been little studied. Nowadays there is much information available of radical addition to carbonyl, thiocarbonyl, nitrile and oxime ether (C=NOR) functional groups. However there has been surprisingly little detailed study of similar reactions involving imines (C=NR) or hydrazones (C=NNHR). Monocyclisation. In the early phase of the research, different types of imine were synthesised and subjected to the standard free radical cyclisation procedure (tributyl-tin hydride / AIBN, added by syringe pump to refluxing solvent) to determination of the regiochemistry of cyclisation onto imines and to assess the synthetic potential of the reaction. The results of this investigative study show that a variety of five and six-membered ring compounds can be synthesised in good yield. A similar study of hydrazones showed that fivemembered rings can be formed under the same reaction conditions. Tandem Reactions. In the next phase, the aim was to extend the methodology to produce more complex structures from acyclic starting materials. If a radical adds to the carbon atom of an imine, a nitrogen-centred (aminyl) radical is generated which can undergo subsequent addition to a suitably positioned double bond to yield a bicyclic amine. This type of reaction is known as tandem or cascade cyclisation. By this method, compounds could be synthesised which have similar structures to natural products. A range of suitably designed imines wct.5. prepared and underwent cyclisation, producing many different types of bicyclic amine in yields varying from moderate to good. The Synthesis of Natural Products. After the successful formation of key bicyclic structures, the third phase of the research aimed at the synthesis of one or more of target natural products. The synthetic strategy used in the tandem reactions outline above was. adapted for these purposes. However the synthesis of the desired compounds could not be achieved in the time, but progress towards their formation was achieved.
3
Tillman, Anna Louise. "Organocatalytic, enantioselective additions to imines". Thesis, University of Cambridge, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.612994.
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Heaney, Mary Frances Teresa. "Cycloaddition reactions of oximes and imines". Thesis, Queen's University Belfast, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335415.
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5
Black, Daniel. "Imines in copper-catalyzed cross-coupling reactions". Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=102960.
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The purpose of this study was to develop new catalytic methods to mediate carbon-carbon bond forming reactions with imines under mild conditions and in a general manner. We found that copper catalysts were compatible in cross-coupling of a range of mild organometallic reagents, providing simple, efficient routes to alpha-substituted amides and amines.Chapter 2 of this thesis describes a new copper-catalyzed multicomponent synthesis of alpha-substituted amides. This reaction was developed based upon previous work in this laboratory, which showed that palladium catalysts were competent in Stille-type cross-coupling of imines, acid chlorides, and organostannanes. While providing a mild method of generating the amide products, a more general procedure able to incorporate a wider range of organostannanes was sought. This chapter details the development of a copper-catalyzed protocol, which, as well as performing the cross-coupling under mild reaction conditions, proceeds with a diverse range of aryl-, heteroaryl-, and vinyl-substituted organostannanes and employs an inexpensive and readily available catalyst. Through this system, control over regioselectivity of addition to alpha,beta-unsaturated imines is also possible.
Chapter 3 demonstrates that, in addition to organostannanes, other substrates are viable in copper-catalyzed cross-coupling with imines and acid chlorides. Herein, the coupling of terminal alkynes with imines and acid chlorides is described, leading to an efficient synthesis of tertiary propargylamides directly from simple starting materials. This synthesis incorporates a wide variety of substituted imines, acid chlorides/chloroformates, and terminal alkynes, providing a rapid synthesis of these useful building blocks (reaction completion in only 15 minutes). In addition, the process is shown to work with aza-aromatic heterocycles, such as pyridine, where the alkynylation occurs exclusively at the 2-position.
Chapter 4 describes the utility of these rapid multicomponent reactions, where the products are directly converted into oxazole heterocycles. Copper-catalyzed- and zinc-catalyzed protocols are developed for the synthesis of secondary propargylamides from silyl-imines, acid chlorides, and terminal alkynes. The secondary propargylamide products are then, in a one pot sequence, transformed into trisubstituted oxazoles.
Chapter 5 describes the development of an atom-economical, non-toxic alternative to the organotin coupling described in Chapter 2. This involves the use of tri- and tetraorgano-indium reagents, which can transfer all of their organic groups in a copper-catalyzed coupling with imines and acid chlorides. This reaction shows good functional group compatibility and further expands the scope of alpha-substituted amides and N-protected amines that can be synthesized through mild copper catalysis.
Chapter 6 explores the enantioselective alkynylation of nitrogen-containing heterocycles. As described in Chapter 3, heterocycles such as pyridine can undergo copper-catalyzed 1,2-addition with terminal alkynes upon activation by chloroformates. As this process generates a stereocenter, it is possible to introduce enantio-control into the reactions by using a chiral copper catalyst. With ligands from the PINAP series, enantioselectivities of up to 84% can be induced in the coupling of nitrogen-containing heterocycles (e.g., quinoline), chloroformates, and terminal alkynes. This provides a mild and simple synthesis of chiral 2-alkynyl-1,2-dihydroquinolines directly from simple starting materials.
6
Kovaricek, Petr. "Motional, reactional and constitutional dynamics of imines". Phd thesis, Université de Strasbourg, 2014. http://tel.archives-ouvertes.fr/tel-01059611.
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Les travaux réalisées lors de cette thèse s'intéressent aux dynamiques de mouvement, de réaction et de constitution des fonctions imines. Les aldéhydes les plus réactives pour cette réaction de condensation ont été identifiées. Un processus d'échange intramoléculaire aléatoire rapide a été observé entre le salicylaldéhyde et l'éthylènediamine dont la vitesse est contrôlée par les substituants, la longueur de la chaîne amine, le solvant et la température. Cette observation conduità l'élaboration de mouvements de déplacement d'abord non-directionnels puis développés pour devenir directionnels. Une sélectivité dynamique réactionnelle a été introduite sur des mélanges d'aldéhydes et d'amines. Elle a été baptisée simpléxité et est utilisée pour de la protection de fonctions. Enfin, la nature dynamique de l'imine a été étudiée à l'interface solide-liquide parmicroscopie à effet tunnel et montre une accélération et une amplification des produits formées sur la surface.
7
Hartley, James Holroyd. "Saccharide accelerated hydrolysis of boronic acid imines". Thesis, University of Birmingham, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369335.
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Rajamäki, Suvi Henna Maria. "Lewis acid mediated cyclisations of methylenecyclopropyl imines". Thesis, University of Southampton, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.401829.
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Guillemin, Jean-Claude. "Les imines non-stabilisees : synthese et reactivite". Rennes 1, 1986. http://www.theses.fr/1986REN10053.
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Guillemin, Jean-Claude. "Les Imines non-stabilisées synthèse et réactivité". Grenoble 2 : ANRT, 1986. http://catalogue.bnf.fr/ark:/12148/cb37598084v.
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Betit, Lyanne. "Derivatization of Azomethine Imines into beta-Aminocarbonyl Motifs". Thesis, Université d'Ottawa / University of Ottawa, 2015. http://hdl.handle.net/10393/32473.
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β-Aminocarbonyl motifs are a privileged substructures in medicinal chemistry and peptidomimetics. As part of our efforts toward metal free aminations, we developed a method for intermolecular amino-carbonylation of alkenes using hydrazones. This method provides access to cyclic azomethine imines containing a β-aminocarbonyl motif. Conceptually, these dipoles can be derivatized into many bioactive compounds, such as 1,3-diamines, β-amino amides and β-amino acids.
The first part of this thesis will present the results on the derivatization of our aminocarbonylation products into various nitrogen-containing molecules, such as β-amino amides, β-amino acids and pyrazolones. More specifically, a short, chromatography-free derivatization of azomethine imines into N-Boc-β-amino amides will be presented.
Following these results, the next chapter will focus on attempts at develop novel aminocarbonylation reactivity between 1,2-diacylhydrazines and alkenes followed by results from our reductive N-N bond cleavage experiments on our cyclic hydrazides.
12
Rumble, Sarah Louise Chemistry Faculty of Science UNSW. "The synthesis of amines and imines organometallic catalysts". Awarded by:University of New South Wales. School of Chemistry, 2005. http://handle.unsw.edu.au/1959.4/23422.
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This thesis describes investigations into the catalysed syntheses of amines and imines using organoiridium and organorhodium complexes with N-donor ligands as the catalysts. These catalysed syntheses were achieved via hydroamination, hydrosilylation, and hydrogenation reactions, as well as tandem hydroamination/imine reduction reactions. An in situ catalysis study found that the most active catalysts for the hydroamination of 4-pentyn-1-amine (1) to give 2-methyl-1-pyrroline (4) were formed from a combination of catalyst components that resulted in an electron deficient metal centre, indicating that an alkyne binding mechanism was most likely. The kinetics of the hydroamination of 4-pentyn-1-amine (1), catalysed by the complexes [Rh(bim)(CO)2][BPh4] (7), [Ir(bim)(CO)2][BPh4] (8), [Rh(bpm)(CO)2][BPh4] (9),and [Ir(bpm)(CO)2][BPh4] (10) (bpm = bis(1-pyrazolyl)methane and bim = bis(Nmethylimidazol- 2-yl)methane) were modelled and compared. The nature of the metal centre was found to have the most influence on the rate of the product release step, while the nature of the N-donor ligand was found to have the most influence on the rate of the substrate binding step. The investigation of the catalysed hydroamination of the phenyl substituted alkynylamines 5-phenyl-4-pentyn-1-amine (2), 4-phenyl-3-butyn-1-amine (13) and 2- phenyl-4-pentyn-1-amine (34) revealed a difference in catalytic activity between the rhodium and iridium complexes depending on the alkyne substituent. A series of novel rhodium(I) complexes were synthesised: [RhClCO(Mes-DAD(Me))] (38), [RhClCO(Mes-BIAN)] (22), [Rh(COD)(Mes-BIAN)][BF4] (39), [Rh2(COD)2(bmimen)](BPh4)2 (40) and [Rh2(CO)4(bmimen)](BPh4)2 (41), where Mes- DAD(Me) = biacetylbis(2,4,6-trimethylphenylimine), Mes-BIAN = bis(2,4,6- trimethylphenylimino)acenapthene and bmimen = 1,2-bis[(1-methyl-2- imidazolyl)methylene-amino]ethane. The cationic complex 40 was found to be an active hydroamination catalyst, while the neutral complexes 38 and 22 were only active in the presence of the tetraphenylborate counterion. A range of imines was found to be efficiently reduced to their respective amines via hydrosilylation or hydrogenation using the iridium(I) complex [Ir(bpm)(CO)2][BPh4] (10) as catalyst. The hydrosilylation reaction was found to be significantly faster in a protic solvent (methanol), giving the desilylated amines without the need for a desilylation step. The mechanism of this reaction was proposed to involve a monohydride iridium(I) complex as a key intermediate. The tandem hydroamination/hydrosilylation of a series of alkynylamine substrates was achieved using the iridium complexes 8 and 10, in which the iridium complex catalyses the two mechanistically distinct reactions in the one-pot. Catalysed tandem hydroamination/hydrogenation reactions were also achieved, but were less facile.
13
Vrankova, Kvetoslava. "Scope of enantioselective reduction of imines with trichlorosilane". Thesis, University of Glasgow, 2009. http://theses.gla.ac.uk/1390/.
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Herein, we report the results of research continuing previous successI in the field of enantioselective organocatalytic reduction of imines with trichlorosilane. Syntheses of various precursors (ketones) and substrates (imines) for the reduction reaction and their reduction following the protocol (Scheme A1) are described in this thesis. 1. Aromatic heterocycles containing nitrogen – good yields of the reduced product (68-85 %), the enantioselectivity depended on steric bulk in proximity to the nitrogen, steric bulk improved the enantioselectivity (up to 78 % ee), probably due to thwarting the coordination of the nitrogen to HSiCl3. 2. Aromatic heterocycles containing sulfur – sulfur in the ring was tolerated well (89 % ee). 3. Aromatic heterocycles containing oxygen – generally good yields (62-90 %), dependence on position isomer was observed: furan-2-yl-derived substrates were reduced in moderate enantioselectivity (45-85 % ee), possibly due to the problem of coordination; in contrast, furan-3-yl derivatives were reduced in good enantioselectivity (77-91 % ee). 4. Non-heterocyclic aromatic or aliphatic – good yields (62-98 %) but varied enantiomeric excess (10-97 %). The high enantioselectivity values (76-97 % ee) were for substrates with significant contrast of the steric hindrance of the groups next to the reaction centre. Furthermore, an example of practical utilisation of the method is presented. Naturally occurring alkaloid N-acetylcolchinol was synthesised in 9 steps and overall 8 % yield (Scheme A2). The stereogenic centre was introduced using our method and afforded the desired enantioenriched amine in 96 % ee.
14
Ishibashi, Eisuke. "Asymmetric addition of cyanide to aldehydes and imines". Thesis, University of Newcastle Upon Tyne, 2011. http://hdl.handle.net/10443/1185.
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Cyanohydrins are a group of compounds that are widely used in industry as common building blocks for asymmetric synthesis. In this thesis, novel methods of synthesizing chiral cyanohydrins are investigated using complexes of transition metals complexed to salen ligands. To start the project, alternative sources of cyanide were investigated. Unfortunately, this investigation could not uncover a new cyanide source that was more effective than trimethylsilyl cyanide as a substrate for titanium(salen) based catalysts. However, this research has led to the finding that KCN / 18-Crown-6 can be used as a co-catalyst in the addition of ethyl cyanoformate to various aldehydes. This has led to a huge reduction in the amount of catalyst that is required to achieve the same enantiomeric excess. In addition, the diastereoselective synthesis of cyanohydrin derivatives using chiral cyanoformates was made possible for the first time. Some of the cyanohydrins synthesized by the new ethyl cyanoformate route were taken a step further, and their use as chiral building blocks was also studied. By using a palladium based catalyst, α,β,-unsaturated cyanohydrins were converted into amides via a two-step reaction. Research into the Strecker reaction was also carried out using vanadium(V)(salen) complexes as catalysts. In this field, the use of phenols as co-catalysts was discovered, and this has led to a world leading enantiomeric excess.
15
Smith, Dan Andrew. "N-phosphino-pyridyl imines : flexible, multi-functional reagents". Thesis, Durham University, 2009. http://etheses.dur.ac.uk/42/.
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Chapter I includes a summary of the chemistry of phosphines and bidentate phosphorus-nitrogen ligands of relevance to this thesis, and highlights their application in transition metal-based catalysis. In addition, a review of the characteristic properties and reactivity of iminophosphoranes and phosphenium cations is presented in preparation for work outlined later in this manuscript. The synthesis and coordination studies of a range of N-phosphino-pyridyl imines with the general structure (C5H5N)(Ar)C=NPR2 (1) {R = alkyl or aryl and Ar = aryl} are reported in chapter II. The molecular structures of their palladium dichloride complexes are presented, highlighting the effect of differing substituents on framework 1 upon the geometry of the complexes. The chemistry surrounding a novel equilibrium between two valence tautomers prepared from reaction of N-lithio pyridyl imine with bis(diisopropylamino)chlorophosphine is presented in chapters III and IV. The tautomers 1,1-bis(diisopropylamino)-3-phenyl-1λ5-[1,3,2]diazaphospholo [1,5-a]pyridine (2c) and bis(diisopropylamino)phosphino(phenyl-pyridin-2-yl methylene)amine (2o) exist in a ratio of 95 : 5, respectively, at ambient temperature. Investigations of the thermodynamic properties, the rate of interconversion and the possible mechanistic pathways of interconversion for 2o/2c have been conducted. The synthesis and characterisation of another equilibrium mixture, that of the tautomers 1,1-bis(diisopropylamino)-3-anthracenyl-1λ5-[1,3,2]diazaphospholo [1,5-a]pyridine (3c) and bis(diisopropylamino)phosphino(anthracenyl-pyridin-2-yl methylene)amine (3o), which exist in a ratio of 30 : 70, respectively, at ambient temperature is reported. Chapter V describes the reaction of bis(diisopropylamino)phosphenium triflate with 1,1-bis(diisopropylamino)-3-phenyl-1λ5-[1,3,2]diazaphospholo[1,5-a]pyridine, which affords 1,1,1',1'- tetrakis(diisopropylamino)-3,3'-diphenyl-1H,1'H-[5,5'-bi-1λ5-[1,3,2]diazaphospholo[1,5-a]pyridinylidene]-1,1'-diium bis(triflate) (4) via a homo-bimolecular coupling process. This apparent ‘oxidative’ coupling by a phosphenium cation has no literature precedent and hence a detailed exploration of the possible mechanism of the reaction is outlined. Comparative reactions involving established oxidants, for example ferrocenium triflate, are examined and also give the diphosphonium salt 4. Chapter VI outlines an exploration of the behaviour of N-dialkyl- and diaryl-phosphino-pyridyl imines in the coordination sphere of low valent palladium species. The isolation and characterisation of a novel dimeric palladium(I) complex is reported, which is found to undergo reactions with chlorobenzene and triphenylphosphine, acting as a source of ‘masked’ palladium(0). These reactions are consistent with redox processes occurring to give palladium(0) or palladium(II) species.
16
Warnock, William James. "1,3-dipolar cycloaddition reactions of imines and oximes". Thesis, Queen's University Belfast, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.356974.
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Mitchell, S. H. "Structural studies on some complex compounds containing imines". Thesis, Cardiff University, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.332450.
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Hepburn, Hamish Bruce. "Enantioselective rhodium-catalysed nucleophilic allylation of cyclic imines". Thesis, University of Edinburgh, 2015. http://hdl.handle.net/1842/17614.
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A highly enantioselective and diastereoselective rhodium-catalysed addition of potassium allyltrifluoroborates to cyclic imines is described within. By utilising rhodium-chiral diene complexes, a wide range of cyclic imines were successfully allylated in high yields and enantioselectivities. Using a variety of more highly substituted allyl reagents, additional stereocentres and further molecular complexity was achieved with good yields, enantioselectivities and diastereoselectivities. Investigations involving isomeric allyl species and deuterated allyl species provided results that gave mechanistic insight, leading to the proposal of a plausible mechanistic pathway and suggested the formation of interconverting allylrhodium intermediates. Furthermore, during these investigations, a highly interesting isomerisation of the allylrhodium intermediate was discovered. Such isomerisation led to the in situ formation of the more complex allylrhodium intermediates which led to complex products upon allylation with cyclic imines that would be difficult to synthesis via other methods. This isomerisation was found to occur for a range of cyclic imines and disubstituted allyltrifluoroborates, proceeding in good yields and diastereomeric ratios. Deuterium studies indicate it is probable that this isomerisation proceeds via a 1,4 rhodium migration and a plausible mechanism is proposed explaining both the connectivity of the products and the relative stereochemistry.
19
Robertson, Gerard Phillip. "The development of catalytic enantioselective additions to imines". Thesis, University of Oxford, 2017. http://ora.ox.ac.uk/objects/uuid:4d69991a-b9ec-452a-bc4b-fcdde13d6503.
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This thesis describes the development and application of catalytic enantioselective additions to imines. Chapter 2 describes the application of bifuntional iminophosphorane (BIMP) organosuperbases, which are a novel class of bifunctional organocatalyst developed in the group to the first 'unactivated' ketimine phospha-Mannich reaction of diethyl phosphite to afford α- aminophosphonic acid derivatives in excellent yields and moderate enantiocontrol (>99% yield, up to 71% ee). Chapter 3 describes the first silver-catalysed enantioselective Mannich reaction of diazoacetates to NBoc protected aldimines. The reaction proved to be broad in scope with respect to the aldimine; with 14 aromatic aldimines reported and variability on the diazoacetate was also tolerated, giving products with good yields (60-86%) and with very high levels of enantioselectivity (88-98% ee) under the control of the bisphosphine ligand, DM-Segphos. The reaction proved to be scalable as demonstrated on a 5.0 mmol scale with a 1 mol% catalyst loading with respect to silver triflate. The Mannich adduct was derivatised to a few useful products with retention of stereochemical configuration. NMR techniques and non-linear effects studies were used to analyse the catalytic system and gain an insight into the mechanism of this reaction. Chapter 4 describes efforts towards the first enantioselective Mannich reaction of ethyl diazoacetate to ketimines. The catalytic system used for this reaction was a modification of the one described in chapter 3, where BEMP was required as a base for reactivity, silver acetate and a chiral aminophosphine ligand made up the catalytic system. Although new reactivity was identified, catalytic turnover was plausibly hampered by reduction of the Ag(I) from the deprotonated diazoacetate. The Mannich adduct was formed in up to 47% yield and up to 42% ee. Chapter 5 describes the discovery of a novel, practical method for determining the longitudinal relaxation times of low γ 3 spin -1/2 nuclei which are scalar coupled to high γ 3 nuclei. The discovery of this method came about from mechanistic investigations into the catalytic system reported in chapter 3. The method makes it possible to extract T1 information for the insensitive low γ 3 nucleus from the EXSY spectrum of the observable high γ 3 nucleus. It is shown how the T1 relaxation constants of Ag can provide valuable insights into the geometrical properties of Ag-bisphosphine complexes. In principle, this method can be applied to any transition metal-ligand system and overcomes the limitations of conventional methods for T1 determination as it allows for the elucidation of T1 relaxation time constants of insensitive transition metal nuclei using standard NMR equipment.
20
Qin, Wenling <1985>. "Synthesis and applications of N-Metallo ketene imines". Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amsdottorato.unibo.it/6381/1/Qin_Wenling_Tesi.pdf.
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N-metallo ketene imines are attractive for the preparation of a wide range of organic compounds. Our research group has been engaged in the preparation and application of the N-metallo imines (SKIs). In this frame we have studied the uncatalyzed reaction of SKIs with isocyanates to give the corresponding malonamides with good yields. It has been demonstrated that the use of SKIs, instead of simple lithium anion of nitriles, is essential for the success of the reaction. A possible explanation assumes that this new reaction proceeds via a silatropism. In the course of our studies, reported in this thesis, the synthesis and the reactivity of N-silyl ketene imines in the preparation of 2,2-diaryl-3,4- dihydroxy- alcanonitrile in an uncatalyzed adol-type reaction has been performed. Our conception has been to use a chiral aldehyde to introduce asymmetric induction at the β-position and at the α-quaternary stereogenic center in the new forming diols. To achieve this goal, we used diarylacetonitrile as the substrate to form the corresponding N-trimethylsylilketene-imines to be reacted with (S)–lactic aldehyde with different protecting groups on the hydroxyl functionality. A number of 2,2-diaryl-3,4-dihydroxy-pentanenitrile were prepared with good to excellent stereo-control and satisfactory yields. Extension of this protocol to other metallo-ketene imines was performed. Accordingly, the preparation of tin ketene imines was attempted in analogy of the corresponding silyl ketene imine. The reaction of tin ketene imines with aldehydes was tested as a new tool for the synthesis of beta-hydroxynitriles starting from carbonyl compounds (aldehydes and/or ketones). Dialkyl(aryl)silyl nitriles and dialkyl(aryl)tin nitriles presents different reactivity. Finally, N-aluminium-ketene imines, as nucleophilic partner in the opening reaction of epoxides were studied. Preliminary positive results foster us to continue our studies in enlightening the scope and the limitations of this new reaction.
21
Qin, Wenling <1985>. "Synthesis and applications of N-Metallo ketene imines". Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amsdottorato.unibo.it/6381/.
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N-metallo ketene imines are attractive for the preparation of a wide range of organic compounds. Our research group has been engaged in the preparation and application of the N-metallo imines (SKIs). In this frame we have studied the uncatalyzed reaction of SKIs with isocyanates to give the corresponding malonamides with good yields. It has been demonstrated that the use of SKIs, instead of simple lithium anion of nitriles, is essential for the success of the reaction. A possible explanation assumes that this new reaction proceeds via a silatropism. In the course of our studies, reported in this thesis, the synthesis and the reactivity of N-silyl ketene imines in the preparation of 2,2-diaryl-3,4- dihydroxy- alcanonitrile in an uncatalyzed adol-type reaction has been performed. Our conception has been to use a chiral aldehyde to introduce asymmetric induction at the β-position and at the α-quaternary stereogenic center in the new forming diols. To achieve this goal, we used diarylacetonitrile as the substrate to form the corresponding N-trimethylsylilketene-imines to be reacted with (S)–lactic aldehyde with different protecting groups on the hydroxyl functionality. A number of 2,2-diaryl-3,4-dihydroxy-pentanenitrile were prepared with good to excellent stereo-control and satisfactory yields. Extension of this protocol to other metallo-ketene imines was performed. Accordingly, the preparation of tin ketene imines was attempted in analogy of the corresponding silyl ketene imine. The reaction of tin ketene imines with aldehydes was tested as a new tool for the synthesis of beta-hydroxynitriles starting from carbonyl compounds (aldehydes and/or ketones). Dialkyl(aryl)silyl nitriles and dialkyl(aryl)tin nitriles presents different reactivity. Finally, N-aluminium-ketene imines, as nucleophilic partner in the opening reaction of epoxides were studied. Preliminary positive results foster us to continue our studies in enlightening the scope and the limitations of this new reaction.
22
Jones, Catrin A. "The asymmetric synthesis of #alpha#-amino acids from imines". Thesis, Bangor University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.263167.
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Barr, Darrin Alexander. "Metal catalysed cycloadditions of imines of #alpha#-amino esters". Thesis, Queen's University Belfast, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334558.
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Nongkunsarn, Pakawan. "Studies of new oxidative rearrangements of imines and esters". Thesis, Keele University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.294198.
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Prado, Viviana da Silva. "Obtenção de complexos de GaIII e InIII com interesse em medicina nuclear a partir do desenvolvimento de ligantes multidentados". Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/75/75135/tde-16012018-103738/.
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Essa tese consiste na preparação de novos compostos de coordenação de Re, Ga e In como potenciais agentes de diagnóstico. Para a síntese desses complexos, foram propostos novos ligantes tiossemicarbazonas, semicarbazonas e iminas derivadas do 2-hidroxi-3-clorometil-5-metilbenzaldeído, o qual foi preparado a partir do reagente comercial 2,6-bis(hidroximetil)-4-metilfenol com rendimento de 76% após três etapas. Os novos ligantes foram obtidos em duas etapas, N-alquilação e condensação, com rendimentos médios de 60 a 75%, respectivamente. Foram obtidos ligantes tridentados, pentadentados e hexadentados, que podem ser empregados na síntese de uma diversidade de complexos, mostrando a versatilidade do reagente proposto. Os ligantes tridentados não se mostraram apropriados para a obtenção de complexos estáveis de ReV, para os quais a caracterização foi dificultosa. A tiossemicarbazona/piridil, como ligante potencialmente pentadentado, formou complexo com ReV com baixo rendimento e possivelmente instável nas condições estudadas. Os ligantes semi e tiossemicarbazonas hexadentados proporcionaram a formação de complexos com GaIII e InIII, com rendimentos de 60 a 90% e de satisfatória estabilidade. O complexo de GaIII hexacoordenado com a bis(semicarbazona) pôde ser obtido na forma neutra zwitteriônica e na forma catiônica como um sal de nitrato, a partir de [Ga(acac)3] e [Ga(NO3)3], respectivamente. Esse mesmo ligante formou complexo neutro zwitteriônico com InIII, quando empregou-se o precursor [In(acac)3] e uma possível mistura de produtos ao empregar-se o [InCl3]. O congênere radioativo do complexo a bis(semicarbazona) foi obtido com rendimentos quantitativos na marcação a partir do 67GaCl3 em 15 minutos e à temperatura ambiente, apresentando razoável estabilidade in vitro (por meio de ensaios na presença de PBS, apo-transferrina e soro de sangue humano) e in vivo (pela análise de sangue e urina após administração em camundongos normais). O estudo de biodistribuição em camundongos demonstrou a captação principal nos intestinos e fígado, relacionando-se com a lipofilicidade (log P 1,40) do composto. Nas condições estudadas, não foi possível obter os radiocomplexos de 67Ga com as bis(tiossemicarbazonas) com rendimentos e pureza satisfatórios. No entanto, obteve-se o radiocomplexo de 111In com a bis(tiossemicarbazona), com grupos metila como substituintes no grupo N, com rendimento quantitativo e alta pureza, progredindo para os ensaios de estabilidade e biodistribuição. Sobre a estabilidade, o radiocomplexo de 111In com a bis(tiossemicarbazona) se mostrou menos estável que o complexo de 67Ga com a bis(semicarbazona), porém com similar comportamento na biodistribuição sendo captado, preferencialmente, no intestino (via de excreção) e no fígado (via metabólica). Ambos complexos são lipofílicos, no entanto, o 111In (log P 2,66) apresenta melhor saída da corrente sanguínea. Os novos radiocomplexos se mostraram promissores para estudos futuros buscando melhoria molecular (por questões de solubilidade, por exemplo) e especificidade via bioconjugação.In this thesis, a design of new Re, Ga and In coordination compounds is proposed. The ligands semicarbazones, thiosemicarbazones and imines could be prepared from 3-(chloromethyl)-2-hydroxy-5-methylbenzaldehyde as initial material. This aldehyde is not available commercially, but it could be obtained in three steps from 2,6-bis(hydroxymethyl)-4-methylphenol in 76 % yield. Using N-alkylation and condensation reactions, the ligands were prepared in 60 to 75 % yields. A series of tridentate, pentadentate and hexadentate ligands were designed to different metal ions, showing the versatility of the chloride/aldehyde reagent. Unfortunately, the ReV complexes were not fully characterized as stable complexes. Semi and thiosemicarbazones, H4bsc and H4btsc, formed GaIII and InIII complexes, as hexadentate ligands in good yields (60-90 %). The hexacoordinated bis(semicarbazone) Ga complex, [Ga(HbscPh)], was obtained as a zwitterion neutral compound and as a cationic form of a nitrate salt, from [Ga(acac)3] and [Ga(NO3)3], respectively. The same ligand, H4bscPh, reacted with [In(acac)3], resulting a zwitterion neutral In complex, [In(HbscPh)], but using [InCl3] a mixture of products was observed. The radioactive congener complex [67Ga(HbscPh)] was obtained in quantitative yields from 67GaCl3 (15 min, at room temperature) therefore the complex presented considerable stability in in vitro (PBS, apo-tranferrin, human blood serum assays) and in vivo (blood and urine after the administration to normal mice). The biodistribuition assays resulted in liver and instestines uptake, which could be related with the lipophilicity of the complex (log P 1,44). In experimental conditions, bis(thiossemicarbazones) 67Ga radiocomplexes were not obtained in reasonable yield and purity. However the radiocomplex [111In(HbtscMeMe)] was obtained in quantitative yields and in high purity (15 min, at room temperature), justifying stability assays. The 111In complex was less stable than 67Ga complex, though the similar uptake. The both complexes are lipophilic, but [111In(HbtscMeMe)] (log P 2,66) presented better blood clearance. The results were promising and new studies toward structural optimizing are proposed, in this way, water soluble complexes and specific agents (coupling to biomolecule) could be prepared.
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Lewis, Kirk Alexander. "Stereoselective synthesis using aminyl radicals derived from α-amino acids". Thesis, Loughborough University, 1997. https://dspace.lboro.ac.uk/2134/32976.
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Chapter 1 is the introduction to the thesis. It contains an overview of amino acids and aminyl radicals. The amino acids section includes material on their synthesis through traditional methods and asymmetric syntheses, as well as the use of radical reactions in their formation. The aminyl radical section gives a description of the nature of the radical and then proceeds with general techniques for aminyl radical formation. A more detailed account of our own group's use of sulfenamides and imines in aminyl radical formation is ·covered and the chapter is ended with a look at the work of aminyl radicals in amino acid synthesis and my subsequent intentions in this area. The preparation and cyclisation of sulfenamide precursors derived from [alpha]-amino acids is discussed in chapter 2. Both the cyclisations of aminyl and urethanyl (introduction of benzyloxycarbonyl and tosyl protecting groups onto amine) radicals onto suitably placed alkenyl substituents were investigated. 5-Exo-trig cyclisation reactions successfully afforded the cyclic products in moderate yield with reasonable diastereoselectivity. The effects of the [alpha]-CO2R (where R = Me or tBu), the size of the amino acid side chain and placement of alkenyl substituent (N-substituted or sidechain containing alkene) are discussed. The use of imines as aminyl radical precursors is explored in chapter 3. [Alpha]-amino acids and aldehydes were condensed and the cyclisation products isolated. The formation of aminyl radicals by 5-exo-trig cyclisation and subsequent H-atom abstraction gave moderate to good yields of N-cyclopentyl substituted a-amino acids. Preparation of the aldehydes is discussed. Tandem cyclisations involving aspects of chapters 2 and 3 are looked at in chapter 4. The preparation of the unnatural a-amino acids required for tandem cyclisation and subsequent formation of the sulfenamide or imine is reported. 5-Exo, 6-exo cyclisation of the sulfenamide derivative gave the tandem product in low yield and with moderate diastereoselectivity. This was in contrast to the imine derived reaction which proved unsuccessful. The remaining chapters incorporate the detailing of experimental relevant to the discussion and the presentation of references quoted throughout the thesis.
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Morere, Alain. "Germa-imines : stabilisation et réactivité : [thèse en partie soutenue sur un ensemble de travaux]". Toulouse 3, 1992. http://www.theses.fr/1992TOU30019.
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Ce travail developpe une etude sur la stabilisation par effets steriques, electroniques, complexation et la reactivite de germa-imines. Le 1er chapitre concerne la trimesitylgermylamine, rare amine primaire stable du germanium. L'encombrement sterique (confirme par rx) previent les attaques nucleophiles sur le metal mais permet une reactivite d'amine primaire. Elle ne conduit pas aux precurseurs de germa-imines envisages mais a des reactions d'echange gen/gecl. Les reactions par transfert monoelectronique ont permis la mise en evidence de radicaux aminyles par rpe. Dans le 2eme chapitre, la n-mesityldimesitylgerma-imine, obtenue par photolyse de l'azoture de trimesitylgermanium ou par reaction du dimesitylgermylene avec l'azoture de mesityle est stabilisee en solution par la trimethylamine et caracterisee chimiquement par reactions de pseudo-wittig. Dans le 3eme chapitre, les derives n-germanies du 2,2-dimethylpropanamide ont ete pleinement caracterises. Cependant la stabilite des precurseurs chlorogermanies est insuffisante pour l'obtention d'une germa-imine stable. Le dernier chapitre montre que les derives n-germanies du 3-amino-thiophene 2-carboxylate de methyle peuvent presenter une chelation interne entre le metal et l'oxygene du carbonyle, favorable a la formation d'une germa-imine stabilisee. La germa-imine isolee est caracterisee par spectroscopie. Sa reactivite vis-a-vis de reactifs protiques est specifique et differente de celle des dimeres cyclodigermazanes
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DEMBELE, YENIMEGUE-ALBERT. "Synthese asymetrique d'alpha-methylene gamma-butyrolactames". Nantes, 1991. http://www.theses.fr/1991NANT2045.
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L'utilisation d'(alpha-bromomethyl) acrylates d'alkyles et d'imines en presence de zinc dans des conditions appropriees demeure la meilleure voie d'acces aux alpha-methylene gamma-butyrolactames. Au cours de cette etude, nous avons realise la premiere synthese totalement selective d'alpha-methylene gamma-butyrolactames secondaires chiraux, avec de bons rendements chimiques par transfert de chiralite lors du couplage d'organozinciques derives d'alpha-bromomethyl) acrylates, et d'une imine portant une copule chirale issue d'un alpha-aminoester ou d'un beta-aminoalcool
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Ramezanian, Merrikh Sabahi. "Synthesis and polymerization of highly electrophilic monomers". Diss., The University of Arizona, 1989. http://hdl.handle.net/10150/184866.
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The experimental results of the current work have two parts. First the synthesis, characterization, and spontaneous copolymerization of two highly electrophilic imines, tricyanomethanimine and methyl 3-aza-α, β-dicyanoacrylate. 1,1-Dichloro-2,2-dicyanoethylene or methyl 3,3-dichloro-2-cyanoacrylate reacted with excess sodium azide to give the corresponding diazides, which smoothly underwent thermolysis in solution to give a solution of the novel tricyanomethanimine or methyl 3-aza-α, β-dicyano-acrylate. Attempted isolation gave only oligomers, but reactions using solution of these imines succeeded. Cyclopentadiene and 2,3-dimethyl-1,3-butadiene afforded hetero Diels-Alder reactions. N,N-Dimethylaniline with tricyanomethanimine gave a p-substituted derivative, but with methyl 3-aza-α, β-dicyanoacrylate only a charge transfer complex was formed. Imines - p-methoxystyrene copolymers were obtained. These imines are as reactive as TCNE, but in contrast can also polymerize. Second, a new unsymmetrically substituted quinodimethane was synthesized, characterized, and copolymerized with electron donating monomers. Oxidation of the 1-cyano-1-phenylmethylene-4-cyano-4-ethoxycarbonylmethylene with MnO₂ gave mostly poly-7,8-dicyano-7-ethoxycarbonyl-8-phenylquinodimethane (DCEPQ), but depolymerization by sublimation yielded 45% of DCEPQ. This compound was a mixture of cis and trans isomers. It was homopolymerized by anionic initiation. High molecular weight copolymers of DCEPQ-styrene, DCEPQ-p-methylstyrene and DCEPQ-p-methoxystyrene(p-MeOSt) were formed spontaneously in 1,2-dichloroethane. All polymerizations occurred by a radical mechanism. High molecular weight polymers formed at low conversion. DCEPQ - p-MeOSt copolymerizations yielded alternating copolymers. From spontaneous polymerization of DCEPQ with NVC no copolymer was obtained. All of these polymerizations begin with a bond forming mechanism and propagate by polyaddition.
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ROSAR, VERA. "The importance of ligand structural diversity in palladium catalyzed polymerization". Doctoral thesis, Università degli Studi di Trieste, 2016. http://hdl.handle.net/11368/2908017.
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Lo scopo principale della presente tesi di Dottorato è stato lo sviluppo di nuovi catalizzatori omogenei per la copolimerizzazione dell'etilene con monomeri vinilici polari, come gli esteri acrilici, al fine di ottenere poliolefine funzionalizzate contenenti una quantità controllata di monomero polare.
Il progetto di ricerca ha riguardato la sintesi e caratterizzazione di complessi di palladio(II) con nuovi leganti azotati non simmetrici di complessità via via crescente, appartenenti alla classe delle alfa-diimmine o a quella delle piridilimmine. Il comportamento catalitico dei complessi di palladio così ottenuti è stato studiato approfonditamente per la copolimerizzazione etilene/metil acrilato. Alcuni dei complessi sono stati testati quali catalizzatori anche per altre reazioni, come la copolimerizzazione CO/vinil arene e la doppia alcossicarbonilazione di alcheni, dimostrando la versatilità dei catalizzatori di palladio con leganti azotati.The main goal of the PhD research was the development of novel homogeneous catalysts for copolymerization of ethylene with polar vinyl monomers, such as acrylic esters, in order to obtain functionalized polyolefins with a controlled content of the inserted polar monomer. The project focused on the synthesis and characterization of palladium(II) complexes with novel non symmetric nitrogen-donor ligands of increasing complexity, and belonging either to the class of alpha-diimines or to the group of the pyridylimines. The catalytic behaviour of the synthesized palladium(II) complexes in the ethylene/methyl acrylate copolymerization was investigated in detail. Some of the catalysts were also applied to other reactions such as the CO/vinyl arene copolymerization and the bis-alkoxycarbonylation of alkenes, demonstrating the versatility of palladium catalysts with N-donor ligands.
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Fornalczyk, Michal. "The fluorinated asymmetric Reformatsky reaction with aromatic ketones and imines". Thesis, University of Leicester, 2011. http://hdl.handle.net/2381/10264.
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One of the most challenging topics in organofluorine chemistry is the asymmetric introduction of fluorine atoms, difluoromethylene and trifluoromethyl groups. Outstanding progress has been made in recent years, but further developments are necessary for chiral fluorinated molecules to be increasingly used in medicinal, agricultural and material chemistry. The enantioselective addition of the fluorinated Reformatsky reagent to aromatic aldehydes in the presence of chiral aminoalcohols to give α,α-difluoro-β-hydroxy esters in good enantiomeric excess is well established. However, the two step protocol is inconvenient because of the need for zinc activation, as well as the relatively high temperatures required for the generation of the fluorinated Reformatsky reagent. Consequently, a one-pot asymmetric Reformatsky reaction of ethyl bromodifluoroacetate with benzaldehyde promoted by diethylzinc under mild reaction conditions (0 oC) has been developed. A very good yield (66 %) and enantiomeric excess (69 % ee) was obtained in the presence of the chiral ligand, N-methylephedrine. The first example of the asymmetric Reformatsky reaction of ethyl iododifluoroacetate with aromatic ketones performed in the presence of (1R,2S)-1-phenyl-2-(pyrrolidin-1-yl)propan-1-ol was developed. The reaction of 2.5 equivalents of the Reformatsky reagent prepared from ethyl iododifluoroacetate and zinc dust gave good isolated yields (63-99 %) and high enantiomeric excesses (75-84 %) with a series of aromatic ketones. However, the more convenient one-step protocol at -40 oC involving activation with diethylzinc gave 62-90 % yields and even better enantiomeric excesses (81-91 %) in a shorter reaction time and with a smaller amount of the expensive ethyl iododifluoroacetate (2.0 equivalents). The protocol of the one-step enantioselective Reformatsky reaction with ketones promoted by diethylzinc was extended to ethyl iodofluoroacetate and excellent yields (84-99 %) and enantiomeric excesses (79-95 %) were obtained. A high level of diastereomeric control was obtained in the chiral reactions with ketones with an extended aliphatic group. The absolute configuration of the new chiral centres for the major enantiomer of the difluorinated esters, and for the major enantiomers of both diastereoisomers of monofluorinated esters obtained in the reactions performed in the presence of (1R,2S)-1-phenyl-2-(pyrrolidin-1-yl)propan-1-ol was determined to be (S). A range of aromatic imines were tested in the convenient one-step asymmetric Reformatsky reaction of ethyl iododifluoroacetate and after optimisation, good enantiomeric excesses (63-68 % ee) were obtained with imines containing a methoxy group in the ortho-position in the presence of N-methylephedrine.
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El, Baz Fatima. "Germa-imines stabilisées par l'effet de substituants attracteurs sur l'azote". Toulouse 3, 1997. http://www.theses.fr/1997TOU30159.
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Le travail presente dans cette these apporte une meilleure comprehension des effets qui stabilisent les especes insaturees a germanium doublement lie a l'azote, et s'interesse egalement a la reactivite de leurs precurseurs les halogenogermy laminolithiens. Il est demontre que les effets electroniques attracteurs sur l'azote (trifluorophenyle, paranitrophenyle, paratoluenesulfonyle) stabilisent les germa-imines. Il est egalement montre que cette stabilisation entraine une diminution de leur reactivite. Trois nouvelles dimesitylgerma-imines tres stables ont ete preparees. Leurs syntheses ainsi que leurs caracteristiques physico-chimiques (masse, rmn,. . . ) sont decrites. Leur reactivite a ete etudiee vis a vis des reactions caracteristiques des germa-imines : addition des reactifs protiques, cycloadditions (2+2), (2+3) ou (2+4), en la comparant a celle de la n-mesityl dimesitylgerma-imine metastable et tres reactive. Quand l'azote porte le substituant 2,4,6-trifluorophenyle, il a ete possible pour la premiere fois de comparer la reactivite de la germa-imine monomere avec celle de son dimere, le cyclodigermazane. Dans les reactions etudiees, la n-2,4,6-trifluorophenyldimesitylgerma-imine est un peu plus reactive que le n-dimesitylgermylidene-4-toluenesulfonamide et la n-4-nitrophenyldimesitylgerma-imine se montre pratiquement inerte. La derniere partie de cette these est consacree aux reactions par transfert monoelectronique (set reactions), pour la premiere fois mises en evidence dans la reaction de germa-imines sur une orthoquinone (3,5-di-tert-butylorthoquinone). Cependant, la n-4-nitrophenyldimesitylgerma-imine est egalement inerte dans ce type de reaction, la conjugaison abaissant suffisamment l'energie du systeme pour empecher le transfert d'un electron sur la quinone.
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MAMOUN, OMAR. "Imines de didehydroaminoacides : application en synthese d'aminoacides carbo ou heterocycliques". Rennes 1, 1993. http://www.theses.fr/1993REN10176.
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Les syntheses d'aminoacides carbo ou heterocycliques, a fonction aminoacide geminee sont effectuees par cycloaddition dipolaire-1,3 ou reaction de diels-alder sur des imines de didehydroaminoacides. Le groupe protecteur imine cumule trois avantages il est introduit ou clive dans des conditions douces et active la double liaison carbone-carbone vis-a-vis des dienes ou des dipoles-1,3 riches en electron. Une synthese de cucurbitine, acide 3-amino-3-pyrrolidine carboxylique et d'analogues substitues est decrite par cycloaddition a un equivalent synthetique de l'ylure d'azomethine non substitue. Les oxydes de nitrile permettent de facon analogue l'acces aux derives des acides 5-amino-5-isoxazolines carboxyliques. Les acides 1-aminocyclopropane carboxyliques sont obtenus par cycloaddition du diazomethane et thermolyse des pyrazolines correspondantes. Les reactions de diels-alder ouvrent une voie d'acces generale aux aminoacides a squelette cyclohexane, norbornane, ou bicyclo 2. 2. 2. Octane
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Omote, Masato. "Development of Asymmetric Syntheses Utilizing C, N-Cyclic Azomethine Imines". 京都大学 (Kyoto University), 2011. http://hdl.handle.net/2433/142393.
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Smith, Joshua J. "Stereoselective Rh- and Cu-catalysed additions to imines and aldehydes". Thesis, University of Nottingham, 2017. http://eprints.nottingham.ac.uk/39370/.
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Chapter 1.Copper-Catalysed Borylative Coupling of Vinylazaarenes and N-Boc Imines. Methodology for the copper-catalysed three-component couplings of vinylazaarenes, bis(pinacolato)diboron, and N-Boc imines has been developed. Oxidation of the initially formed boron species gives azaarene-containing, Boc-protected amino alcohols with reasonable to good diastereoselectivities. Additionally the synthetic utility of the reaction products have been demonstrated. The crude boron species have been shown to undergo a Suzuki-Miyaura cross coupling to give further functionalised products. Finally, facile deprotection of the reaction products is possible. Chapter 2. Chain Walking of Allylrhodium Species in Rhodium-Catalysed Nucleophilic Allylations of Imines and Aldehydes. Allylrhodium species derived from δ-trifluoroboryl β,γ-unsaturated esters undergo chain walking towards the ester moiety. The resulting allylrhodium species react with imines to give products containing two new stereocenters and a Z-alkene. By using a chiral diene ligand, products can be obtained with high enantioselectivities. A pronounced matched/mismatched effect with the chirality of the allyltrifluoroborate is also observed. In an analogous reaction a rhodium-hydride species has been shown to catalyse the addition of diene esters and aldehydes via allylrhodium intermediates which also undergo chain walking towards the ester moiety. The methodology enables allylation of aromatic aldehydes with compounds containing both diene and ester functionalities linked by carbon chains of up to eight carbons in length.
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Meirelis, Francine Paulina. "Síntese de gem-dicloroaziridinas empregando KF/Al2O3". Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/97/97136/tde-24072014-154818/.
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Nos últimos anos, questões ambientais têm merecido destaque na mídia nacional e internacional. A química tem uma grande participação nos dias atuais com os inúmeros produtos fundamentais à humanidade. A sua presença pode ser destacada desde diversos combustíveis aos mais complexos medicamentos. As reações de síntese orgânica devem ser guiadas por novas práticas mais sustentáveis. Nesse campo, tem-se o conceito da Green Chemistry ou Química Verde, que consiste na estratégia em desenvolver metodologias e processos que usem e gerem a menor quantidade de materiais tóxicos e/ou inflamáveis ou reaproveitáveis. Com o intuito de contribuir com a Química Verde, estudou-se a síntese de iminas que consistiu da primeira etapa do processo de aminação livre de solventes orgânicos e apresentaram rendimentos superiores a 95,0 %; gem-dicloroaziridinas foram preparadas a partir de inserção de diclorocarbeno em iminas em condições mínimas de solvente orgânico, utilizando como catalisador o KF/Al2O3 e com rendimentos superiores a 98,0%. As gem-dicloroaziridinas foram convertidas em amidas por hidrolise, na ausência de solvente e com rendimentos superiores a 98,0%. Dentro do conceito de Química Verde foram preparadas as seis iminas: N-benzilfenilmetanoimina, N-fenil-furilmetanoimina, N-fenilfenilmetanoimina, N-fenil-(4-metoxifenil)-metanoimina, N-benzil-(4-metoxifenil)metanoimina e N-furfurilfurilmetanoimina; duas gem-dicloroaziridinas: 2,2-dicloro-1,3-difenilaziridina e 1-benzil-2,2-dicloro-3-fenilaziridina e duas amidas: cloro-fenilacetanilida e N-benzil-cloro-fenilacetamida.For the last years Environmental issues have deserved featured in the National and International media. Chemistry has had great participation on currently days with countless products which are fundamental to humanity. Its presence can be detached from various fuels to the most complex drugs.The organic synthesis reactions should be guided by more sustainable new practices. In this field, the Green Chemistry concept or (Química Verde) strategy which aims to develop methodology and and/or processes which use and generate the minimum quality of toxic inflammable material. With the purpose of contribute to green chemistry, we studied the synthesis of imines which consisted of the first stage of the process of amination, free of organic solvents and have yields higher than 95%; gem-dichloroaziridine were prepared from the imines insertion dichlorocarbene in a minimum of organic solvent conditions, using as catalyst KF/Al2O3 and yields higher than 98%. The gem-dichloroaziridines were converted to amides by hydrolysis in absence of solvent and yields higher than 98.0%. Within the concept of Green Chemistry were prepared six imines: N-benzyl- phenylmethanimine, N-phenyl-2- furylmethanimine, N-phenyl- phenylmethanimine, N-phenyl-(4-methoxyphenyl)methanimine, N-benzyl-(4-methoxyphenyl)metha-nimine,N-(2-furylmethyl)-2-furylmethanimine; two gem-dichloroaziridinas: 2,2-dichloro-1,3-diphenyla-ziridine and 1-benzyl-2,2-dichloro-3-phenylaziridine and two amides: chlorophenylacetanilide and N-benzyl-chloro-phenylacetamide.
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Pandrapragada, Ravi Kumar. "Synthesis and characterization of novel phosphinimine ligand systems for potential applications in radiopharmaceuticals". Diss., Columbia, Mo. : University of Missouri-Columbia, 2007. http://hdl.handle.net/10355/5100.
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Thesis (M.S.)--University of Missouri-Columbia, 2007.The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed Nov. 1, 2007). Vita. Includes bibliographical references.
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Granier, Michel. "Synthèse, structure et réactivité de nitrilimines stables". Toulouse 3, 1990. http://www.theses.fr/1990TOU30125.
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Les nitrilimines ont ete tres utilisees en synthese organique dans des cycloadditions dipolaires-1,3. Jusqu'a present, elles n'ont pu etre observees qu'en matrice a 77 k. Une methode de synthese originale nous a permis d'obtenir une nitrilimine stable a temperature ambiante (point de fusion de 100#oc sans decomposition): l'action du sel de lithium du bis (diisopropylamino)thiophosphinodiazomethane sur la bis(diisopropylamino) chlorophosphine conduit a la formation de la cbis(diisopropylamino) thiophosphino nbis(diisopropylamino) phosphino nitrilimine compose qui a fait l'objet d'une etude par diffraction de rayons x. Cette nitrilimine se rearrange thermiquement en son isomere diazoique. Ce resultat est la premiere mise en evidence directe de l'isomerisation nitrilimine-diazo. Sa reactivite met en evidence un caractere nucleophile. Les reactions de cycloadditions dipolaires 3+2 semblent tres regioselectives. Cependant, un manque de stereoselectivite a ete observe. Cette nitrilimine peut aussi reagir formellement sous forme de dipoles 1-4 avec des dipolarophiles tres pauvres en electrons. L'action de la tetrachloroorthobenzoquinone conduit a la formation d'un compose tres original et tres stable: un pseudo complexe de nitrene sur un atome d'oxygene. Nous avons mis en evidence un intermediaire stable a 50#oc, qui semble etre une isodiazirine, compose qui est le seul isomere jamais observe du diazomethane. Dans le cas d'addition du methyltriflate, nous obtenons la premiere nitrilimine electrophile stable dont la structure a ete etudiee par diffraction de rayons x
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Laouiti, Anouar. "Etude de la synthèse et de la réactivité d'ynimines". Versailles-St Quentin en Yvelines, 2013. http://www.theses.fr/2013VERS0056.
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Les triples liaisons font partie des fonctions les plus importantes en chimie organique du fait leur grand potentiel synthétique. Parmi toutes les classes d’alcynes, ceux étant directement substitués par un atome d’azote, ont attiré l’attention de nombreux groupe. Une famille de cette classe, les ynimines, a été très peu étudiée à cause des difficultés liées à leur préparation. Dans ce contexte, et dans la continuité des travaux du laboratoire, nous nous sommes intéressés au développement des nouvelles méthodes de synthèse de ces composés. Nous avons ainsi développé deux méthodes générales pour la préparation des ynimines, la première étant basée sur le couplage oxydant d’alcynes terminaux et d’imines en présence d’une quantité catalytique de cuivre (II) et la deuxième méthode, qui est plus douce, reposant sur l’alcynylation oxydante directe d’imines avec des alcynures de cuivre. Ces composés se sont révélés d’être des précurseurs pour la synthèse des azadiène, des nitriles quaternaires, des nitriles insaturés, des cétènimines et des amides α,β-insaturésTriple bonds are among the most important moieties in organic chemistry because of their great synthetic potential. Among all classes of alkynes, those being directly substituted by a nitrogen atom have attracted the attention of many groups. A family belonging to this class, the ynimines has been little studied because of difficulties encountered for their preparation. In this context, and in continuity with previous work from our laboratory, we have been interested in the development of new methods of synthesis of these compounds. We have developed efficient and mild methods for the preparation of ynimines based on a copper-catalyzed alkynylation of imines with terminal alkynes and on a direct oxidative alkynylation of imines with alkynylcopper reagents. These building blocks were shown to be especially suitable precursors for the synthesis of azadienes, quaternary nitriles, unsaturated nitriles, cetenimines and α,β-unsaturated amides. Indoles by intramolecular carbolithiation or carbocupration of ynamides. These new reactions allow for a straightforward and original entry to these various heterocyclic systems, which could be highlighted by a formal synthesis of a bioactive compound: Sarizotan. All together, this work should contribute to further expand the synthetic utility of ynamides as well as intramolecular carbometallation reactions in organic synthesis
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Grace, Jake. "The Rh catalysed asymmetric transfer hydrogenation of imines; a mechanistic study". Thesis, University of York, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.485090.
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In a study of the mechanism of Catalytic Asymmetric Transfer Hydrogenation (CATHy), we report the synthesis and characterisation of the monotosylated diamine. ligands (R,R and S,S)-p-fluorobenzenesulfonyl-l,2diphenylethylenediamine (FsDPEN) and (R,R and S,S)-p-lbutylbenzenesulfonyll, 2-diphenylethylenediamine (BusDPEN) and the corresponding Cp*Rh .complexes Cp*RhO(TsNCHPhCHPh.NH2) (i), Cp*RhO(FsNCHPhCHPhNlli) (2) and Cp*RhCI(BusNGIPhCHPhNlU) (3). (1) has been shown to react with NaOMe to form Cp*Rh(H)(TsNCH:I'hCHPhNH2) (5) as the)najor product,.as evidenced by NMR spectroscopy, and also a small amount of Cp*Rh(TsNCHPhCHPhNH) (4), as -evidenced byUV-Vis spectroscopy. The monotosylated diamine ligand p-toluenesulfonyl-o-phenylenediamine (TsOPDA) has also been synthesised and characterised, and the 16-electron catalytic intermediate Cp*Rh(TSNC6H4NH) (6) has been isolated and characterised crystallographically. An important product of catalyst deactivation [(Cp*Rh)2(Il-H)(1l-O)(1l-HC02)][BPh4] (8), has been isolated and . characterised crystallographically. The reactivity of (1)~ (2) and (3) with CO, LiBr, KI, AgOTf and IBuNC has been studied and the complexes [Cp*Rh(CO)(OCNTsCHPhCHPhNlU)]<' (9), Cp*RhBr(TsNCHPhCHPhNILY (11), Cp*RhI(TsNCHPhCHPhNlU) (12), [Cp*Rh(FsNCHPhCHPhNlli)][OTf] .. (13) and [Cp*Rh(tBuNC)(TsNCHPhCHPhNlli)][PF6] (14b) have all bee? synthesised and characterised. Crystal structures are reported for all complexes other than (9) and (14b). Whilst (11) and (12) crystallise in chiral space groups, (13) crystallises as a mixture of enantiomers in an achiral space group.. The CATHy of 6,7-dimethoXY-l-methYI-3,4-dihYdroisoquinoline (Sla) with all the complexes described above (apart from (9» has been reported. A preliminary kinetic study of the reduction of (Sla) With the [Cp*RhCh]2 / TsDPEN system and TEAF as hydrogen donor has shown the reaction to be first order in catalyst and zero order in substrate. The TOF of the system has been determined as 8100 ± 180 mol product mol catalysr1 hour:,l. Comparative rates have been measured for complexes [Cp*RhCh]2 / TsDPEN, (I),. (2), (3) and (6) as catalysts, they are 1.00, 1.10, 1.21, 0.96 and 0.09 respectively.
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Hill, Stuart John. "Construction of copper co-ordination architectures using di- and tri-imines". Thesis, University of Nottingham, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285592.
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Power, Nicholas Patrick. "Kinetics and mechanisms of reactions of N-arylsulfonyl derivatives of imines". Thesis, University of Ulster, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.267781.
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Hanly, Ann Marie. "Mechanisms of reactions of N-arylsulfonyl derivatives of imines and oxaziridines". Thesis, University of Ulster, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.260538.
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Dad, Mohammad M. (Mohammad Mehdj). "Aminoketene. Cycloaddition of Ketenes and Imines to Yield β- or δ- Lactams". Thesis, University of North Texas, 1991. https://digital.library.unt.edu/ark:/67531/metadc332534/.
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The purpose of this investigation was to provide a systematic study of the cycloaddition pf (N-alkyl-N-phenylamino)- methoxy-and dichloroketenes to various imines and to investigate the stereochemistry of these cycloadditions.
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Zhang, Yaming. "Electron spin resonance studies of organic radical cations : theoretical and experimental approach". Thesis, Liverpool John Moores University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.313090.
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Bouhadir, Ghenwa. "Réactivité du premier phosphazide cis stable et du phosphazène correspondant. Préparation de nouveaux composés onio du phosphore". Toulouse 3, 1996. http://www.theses.fr/1996TOU30205.
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La 1,2,3,4#5-triazaphosphinine, preparee dans notre equipe en 1993, constitue le premier exemple de phosphazide stable a temperature ambiante possedant un enchainement pnnn de configuration z. La perte d'une molecule de diazote intervient au reflux du toluene et permet d'acceder au 1,2#5-azaphosphete, qui est un heterocyclobutadiene. Dans un premier temps, nous nous sommes interesses au comportement de la #5-triazaphosphinine en tant que ligand vis a vis des metaux de transition. . . .
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Hubert, Cathy. "Accès à des acides alpha-aminophosphoniques. Effets des ultrasons et mécanisme". Toulouse 3, 1994. http://www.theses.fr/1994TOU30252.
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Le sujet traite concerne une etude synthetique et theorique d'une reaction a mecanisme complexe donnant acces a des molecules aminophosphore qui sont des aminoacides dans lesquels la fonction carboxylique a ete remplacee par fonction acide phosphonique. Les analogues phosphores des -aminoacides sont connus pour leurs proprietes biologiques (antibacteriennes, antibiotiques) ou phytosanitaires importantes. Nous avons synthetise de nouveaux acides aminophosphoniques, contenant un reste thiophene ou pyrrole, dans le but d'en evaluer leurs proprietes. Ces preparations ont ete effectue par les methodes habituelles: reactions sans solvant par chauffage. Dans un deuxieme temps, il a ete montre que les reactions sont sensibles a l'activation par ultrasons, ce qui a motive une etude du mecanisme. Un processus radicalaire a ete mis en evidence pour certains substrats, alors que d'autres reagissent de maniere ionique. D'une maniere generale on peut dire que la reaction etudiee peut se produire par un continuum de mecanisme, selon la variation des groupes substituants de l'atome de phosphore. Un tel phenomene rare en chimie organique, constit ue certainement un point de depart pour des futures recherches
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Gandon, Vincent. "Nouvelles méthodes de synthèse à partir des complexes du ziconium". Reims, 2002. http://www.theses.fr/2002REIMS009.
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Ce mémoire est consacré à la présentation des nouvelles méthodes de synthèse que nous avons mises au point grâce aux complexes du zirconium. Dans un première partie, nous avons détaillé la préparation des complexes zirconocéniques, leurs propriétés et leurs applications en synthèse. Dans la deuxième partie, nous avons décrit une nouvelle méthode de préparation des cyclopropanes, à partir des aldhéhydes et des cétones, grâce à l'utilisation du complexe Cp2Zr(éthylène) et d'un acide de Lewis. Basée sur le concept de contraction déoxygénative des oxazirconacycles, cette réaction de cyclopropanation a ensuite été adaptée au cas des éthers allyliques, eux-mêmes transformés en cyclopropanes substitués avec une bonne diastéréosélectivité. Dans la troisième partie, nous nous sommes intéressés à l'activation des 3-silyloxy-2-aza-1,3-diènes. Nous avons traité ces hétérodiènes par le complexe Cp2Zr(but-1-ène) et obtenu des zirconaoxazolines C-silylées, suite à un arrangement de type rétro-Brook. La présence de ces intermédiaires particulièrs nous a permis de transformer les 3-silyloxy-2-aza-1,3-diènes en amide α-silylés, en amides α,β-insaturés ainsi qu'en β-cétoamides. Nous avons également constaté que les 2-aza-1,3-diènes étaient susceptibles de réagir avec les organomagnésiens, à condition d'introduire une quantité catalytique de Cp2ZrCl2 dans le milieu réactionnel. Cette découverte nous a amené à mettre au point une réaction plus générale d'éthylmagnésiation des imines, catalysée par des complexes du zirconium. Cette réaction fait l'objet de la quatrième partie de ce document. Des amines possédant un carbone quaternaire en α de l'atome d'azote ont ainsi été préparées très facilement à partir des cétimines.
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Klein, Aurélie. "Synthèse d'allènes électrophiles polyfonctionnalisés en série racémique et en série optiquement active : Vers la synthèse de produits naturels bioactifs appartenant à la famille des iphionanes". Université Louis Pasteur (Strasbourg) (1971-2008), 2005. http://www.theses.fr/2005STR13145.
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Le travail décrit dans ce mémoire porte sur la synthèse et la réactivité de différents ω-cétoesters acétyléniques (carbonés et hétérocycliques) en série racémique et en série optiquement active vis-à-vis de différentes bases. Après avoir mis au point une méthode d’accès facilement modulable à ces composés, nous nous sommes intéressés à la réactivité intramoléculaire des ω-cétoesters acétyléniques vis-à-vis de différentes bases comme par exemple le TBAF et le t-BuOK. Nous avons montré qu’il était possible, suite à de nouvelles réactions en cascade, d’accéder à des dérivés spiraniques, à des esters alléniques, à des oxacyles ou encore à des dérivés tricycliques polyfonctionnalisés, ceci étant fonction de la nature de la base utilisée. Nous avons également essayé de rationnaliser nos résultats par des calculs semi-empiriques d’orbitales moléculaires, qui ont confirmé nos résultats expérimentaux. Ceci nous a permis de développer de nouvelles voies d’accès vers la synthèse de produits naturels sesquiterpéniques bioactifs appartenant à la famille des IphionanesThis thesis deals with the synthesis and the reactivity of a large variety of acetylenic ω-ketoesters both in racemic and optically active series. First of all, we have performed new synthetic approaches, which can be modulated easily, to afford this kind of compounds. Then, we have focused our attention on the intramolecular reactivity of the acetylenic ω-ketoesters, toward different bases and in particular TBAF and t-BuOK. We have shown that depending on the base which is used in the reaction, we are able, using new cascade reactions, to have direct access to spiranic derivatives, to allenic esters, to oxacycles or to tricyclic derivatives. We have also tried to rationalize our results by means of semi-empirical MO calculations. This methodology was finally used to develop novel synthetic approaches for the preparation of sesquiterpenic naturel bioactive products belonging to the Iphionane family
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Baudelle, Romuald. "Synthèse parallèle de trois chimiothèques de tétrahydroquinoléines polysubstituées et de deux chimiothèques d'acylsulfamates : Texte imprimé". Lille 1, 1999. https://pepite-depot.univ-lille.fr/LIBRE/Th_Num/1999/50376-1999-443.pdf.
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La chimie combinatoire est aujourd'hui intégrée au processus de découverte de nouveaux médicaments. De nombreuses réactions chimiques ont été utilisées pour la synthèse de chimiothèques diverses dans le cadre du criblage primaire et pour la synthèse de chimiothèques focalisées. Un vif intérêt est porté pour les réactions qui produisent des hétérocycles ou des squelettes apportant de nombreux éléments de pharmacophore. Dans la première partie de ce rapport, nous présenterons la chimie combinatoire et son évolution grâce à deux articles, le premier publie en 1995 et le second à paraître fin 1999. La seconde partie détaillera la mise au point d'un protocole de synthèse de tétrahydroquinolines en phase homogène, utilisant la condensation d'une imine et d'un alcène. Le mécanisme de la réaction sera discuté à travers diverses expériences. Les règles de réactivité des trois partenaires impliqués dans la réaction ainsi que la méthode générale de sélection des monomères seront présentées. En utilisant la diversité des aldéhydes et des anilines, une chimiothèque de 8. 240 hétérocycles a été synthétisée, divisée en trois sous-chimiothèques selon l'alcène et le catalyseur sélectionnés, et selon le nombre d'étapes chimiques impliquées dans la synthèse. La dernière partie de l'exposé concerne la mise au point de la synthèse de sulfamates à partir de phénols et du chlorure de sulfamoyle, et la comparaison de deux protocoles. Les règles de réactivité des phénols seront présentées. La réactivité des sulfamates a été évaluée et comparée à celle d'aminés plus courantes. Les conditions d'acylation de ces nucléophiles ont été optimisée par l'utilisation du carbonyldiimidazole en tant que réactif de couplage. La synthèse d'une chimiothèque de 3. 520 molécules sera présentée, comprenant une sous-chimiothèque de 1. 920 acylsulfamates et une seconde sous-chimiothèque de 1. 600 diacylsulfamates, ces derniers utilisant un tenseur symétrique de type disulfamate.