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Dissertations / Theses on the topic 'Hydrazine Synthesis'
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1
Li, Qing Hua. "Second generation camphor sulfonyl hydrazine (CaSH II) organocatalysis." HKBU Institutional Repository, 2013. http://repository.hkbu.edu.hk/etd_ra/1525.
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Chen, Lingyan. "CaSH (camphor sulfonyl hydrazine) and CSI (chiral sulfonimide) organocatalysis." HKBU Institutional Repository, 2010. http://repository.hkbu.edu.hk/etd_ra/1186.
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Ghassemi, Hossein. "Synthesis and properties of novel polyimides utilizing hydrazine." Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=28451.
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Hydrazine reacts with phthalic anhydride to give a mixture of cyclic hydrazide and N-aminophthalimide. However, the N-aminoimide is exclusively formed in high yield by the reaction of 1,8-naphthalic anhydride with hydrazine. N-aminoimides act as amines and react further with cyclic anhydrides to yield stable bisimides containing an N-N linkage. The syntheses of several bis(N-aminoimide)s from the corresponding bisanhydrides which contain the naphthalic anhydride moiety have been described. Novel high molecular weight polyimides have been synthesized by the reaction of these bis(N-aminoimide)s with cyclic dianhydrides. Most of the polymers are amorphous and are soluble in solvents such as chloroform, o-dichlorobenzene, N-methylpyrrolidinone and m-cresol. Only those polyimides having less flexible groups in their structure or containing a significant amount of perylene units show some degree of crystallinity.All of the polymers show remarkably high glass transition temperatures, as high as 455$ sp circ$C. Their 5% weight loss by thermogravimetric analysis in an atmosphere of air or nitrogen are all above 440$ sp circ$C. Most of these polymers are highly fluorescent. Their emission spectra are in the visible region and show some evidence for an excited energy transfer and molecular aggregation.
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He, Hao. "Organocatalysis : hydrazine and sulfonimide as new functionalities in asymmetric organocatalysis." HKBU Institutional Repository, 2009. http://repository.hkbu.edu.hk/etd_ra/1104.
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Samanta, Susnata. "Reversible carbon dioxide gels, synthesis and characterization of energetic ionic liquids, synthesis and characterization of tetrazole monomers and polymers, encapsulation of sodium azide for controlled release." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/22602.
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Thesis (Ph. D.)--Chemistry and Biochemistry, Georgia Institute of Technology, 2007.Committee Chair: Prof. Charles L. Liotta; Committee Member: Prof. Arthur J. Ragauskas; Committee Member: Prof. Charles A. Eckert; Committee Member: Prof. John D. Muzzy; Committee Member: Prof. Rigiberto Hernandez.
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Clavette, Christian. "Synthesis of Beta-Aminocarbonyl Compounds and Hydrazine Derivatives Using Amino- and Imino-Isocyanates." Thesis, Université d'Ottawa / University of Ottawa, 2015. http://hdl.handle.net/10393/32004.
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Over the past recent years, β-aminocarbonyls have been of great interest to medicinal chemists. As a practical method to obtain these moieties, alkene aminocarbonylation, accounting for the formation of a C-N and a C-C bond, has been the subject of limited research efforts (very specific intramolecular metal-catalyzed variants have been reported). Direct aminocarbonylation of alkenes constitutes a challenging and an important potential innovation in the synthesis of β-aminocarbonyls such as β-amino acids. The research efforts described in the present thesis have been primarily directed towards the development of concerted pathways for the amination of alkenes using hydrazine derivatives as bifunctional reagents. Building on our previous report on the reactivity of hydrazides, progress on the aminocarbonylation of alkenes along with the synthetic scope of this reactivity are herein provided. Therefore, the first part of the present thesis (Chapter 2) focuses primarily on the development of thermolytic conditions for the intramolecular aminocarbonylation of alkenes using amino-isocyanates. Alongside, development of imino-isocyanates have provided complementary synthetic tools for aminocarbonylation. The second part (Chapter 3) describes the work accomplished towards intermolecular aminocarbonylation of alkenes and the synthesis of complex azomethine imine products (Chapter 3). Finally, the last part of the discussion (Chapter 4) will be on the development of new hydrazide reagents for the intramolecular Cope-type hydroamination of alkenes. In doing so, description of the synthetic utility of amino-isocyanates as amphoteric reagents for cascade reactions and heterocyclic synthesis will be provided.
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Mojica, Mike. "Investigation of new synthetic reactions: the synthesis of hydrazines via the Aza-Lossen rearrangement, the synthesis of carbamoyl azides from amines, and deprotection reactions using water at elevated temperatures." Diss., Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/51791.
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This thesis explores three rare synthetic routes: the synthesis of hydrazines via the aza-Lossen rearrangement, the synthesis of carbamoyl azides from amines, and deprotection reactions using water at elevated temperatures. The aza-Lossen reaction was found to be ideal at “infinite dilution” conditions and could be performed with both aryl and alkyl example. Carbamoyl azides could be synthesized in high yields from both aryl and alkyl amines. The carbamoyl azide reaction was found to be much more efficient with Cs (+1) present. Lastly, water at elevated temperatures conditions was efficient at removing various amine and hydroxyl protecting groups.
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Huttenhower, Hillary Anne. "Development of new chemistry for a dual use hydrazine thruster, switchable room temperature ionic liquids, a study of silane grafting to polyethylene and its model compounds, synthesis of the novel hydrazine replacement fuel molecules 1,1-dimethyl-2-[2-azidoethyl]hydrazine and 1,1-dimethyl-2-[2-azidoethyl]hydrazone." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/41055.
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This thesis focuses on the development of new compounds or new processes that are more environmentally friendly and economical than those currently in use. The decomposition of hydrazine, a well established liquid rocket fuel for both the aerospace and defense industries, to the product ammonia is studied. Control of this reaction will allow hydrazine to be used as a propellant for both chemical and electric propulsion. From this a dual stage thruster will be developed that will be more efficient than current systems decreasing the amount of propellant needed and allowing for either a larger mission payload or a longer duration of individual missions. Hydrazine, while beneficial and well established, is also highly toxic, so other work in this thesis focuses on the synthesis of the novel molecule 1,1-dimethyl-2-[2-azidoethyl]hydrazine or DMAEH and its hydrazone intermediate 1,1-dimethyl-2-[2-azidoethyl]hydrazone or De-DMAEH as less toxic hydrazine replacements.
Novel "switchable" ionic liquids have been investigated in this research. These are solvents that can change from molecular liquids to ionic liquids and back, simply with the addition or removal of CO₂ from the system. They can be used for a variety of applications, including as solvents for a reaction and separation system. Due to the recyclable nature of these solvents, waste is decreased making their development and implementation both environmentally and economically beneficial. Finally, the grafting reaction of vinyl silanes onto a hydrocarbon backbone is investigated. Fundamental work is being performed to study the graft distribution, selectivity and mechanism by which this reaction occurs. A more thorough understanding of how this reaction proceeds will allow for the development of a more efficient industrial process.
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Zerkout, Saïd. "Synthèse d'hydrazino peptides." Vandoeuvre-les-Nancy, INPL, 1994. http://www.theses.fr/1994INPL052N.
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La modification de la liaison amide dans les peptides a plusieurs conséquences potentielles: une biodégradabilité réduite, une possible modulation structurale due aux perturbations du réseau de liaisons hydrogène, et éventuellement, une bio-activité modulée pour l'analogue pseudopeptidique résultant, sans nécessiter de changer les chaines latérales. Nous avons étudie les perturbations structurales induites par la substitution d'une liaison amide par un groupe hydrazide dans diverses séquences mono-, di- et tripeptidiques protégées à leurs deux extrémités par une fonction amide, et contenant l'analogue hydrazine de la proline ou de l'alanine. L'analyse conformationnelle a été conduite à l'état solide par diffraction des rayons X, en solution par spectroscopie infrarouge et résonance magnétique nucléaire du proton, et par modélisation moléculaire. Après des considérations générales sur les structures des peptides et pseudopeptides, l'aspect chimique et technique de ce travail est présenté dans le second chapitre. Le troisième chapitre rassemble les données spectroscopiques et les conclusions sur les structures présentes qui sont ensuite discutées en référence aux séquences peptidiques originelles. La conclusion principale est que le groupe hydrazide induit localement un repliement du à la nucléophilie de l'oxygène du carbonyle et de l'azote alpha qui participent tous les deux a une liaison hydrogène bifide avec le site N-H amide immédiatement situe en aval. La conformation repliée qui en résulte est très stable, et capable de donner naissance à une forme globalement repliée de la molécule, de façon très semblable au repliement beta dans les peptides
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Tumey, Jonathan Michael. "Synthesis and Reactivity of Sydnone Derived 1,3,4-Oxadiazol-2(3H)-ones." Wright State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=wright1515170202954677.
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Loiseau, Francis. "Cope-type Hydroamination of Alkenes with Hydroxylamines and Hydrazines - Scope and Mechanism." Thèse, Université d'Ottawa / University of Ottawa, 2013. http://hdl.handle.net/10393/23794.
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Hydroamination stands as a desirable approach to nitrogen-containing molecules, which have important applications ranging from pharmaceuticals (fine chemicals) to paints, coatings, insecticides and agrochemicals (bulk chemicals). It features the use of alkene and alkyne starting materials, which are abundant and rarely used in the formation of C-N bonds. This work aims at building on the improved Cope-type reactivity developed in the Beauchemin group by expanding the reach of the reaction and understanding its mechanistic complexities. The first part of this thesis describes the development of cascade reactions to provide a thermodynamic driving force for the intermolecular Cope-type hydroamination of alkenes. The methodology serves as a proof of concept that the dipolar reaction intermediates can be engineered to further react irreversibly to more stable products, and has shown potential in improving the syntheses of natural alkaloids. The second part of the thesis describes the expansion of Cope-type hydrazide hydroaminations through a systematic investigation of hydrazine analogs as reactants. Optimized reagents are featured in the first reported intermolecular Cope-type hydrohydrazidation of alkenes. Mechanistic investigations and isolation of ammonium ylide intermediates support a 5-membered concerted and planar mechanistic pathway for hydrazide hydroaminations, similar to that observed with hydroxylamines. The final section presents mechanistic data disproving a previously assumed difficult proton transfer step in the hydroamination using hydroxylamines. From such findings, early results are presented towards a hydrogen-bond catalyzed hydroamination, which has potential applicability across the field of Cope-type hydroaminations and beyond.
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Pinar, Ayse Nur. "Reaction Of Propargyl Aldehydes With Hydrazinium Salts: Synthesis Of Ferrocenyl And Phenyl Substituted Pyrazoles." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/3/12609769/index.pdf.
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Pyrazoles have been focus of a large number of investigations in the design and
synthesis of novel biologically active agents that show remarkable medicinal
activities. Although pyrazoles have been studied for over a century as an important
class of heterocyclic compounds, they still continue to attract considerable attention
due to the wide range of medicinal activities they possess. Recent studies have
shown that combination of a ferrocenyl unit with structural features of pyrazoles can
lead to products with enhanced or/and unexpected biological activity since several
ferrocene derivatives have already been shown to be active against a number of
tumors. As a result, we have investigated the reaction of 3-ferrocenylpropynal with
hydrazinium salts. As anticipated, these reactions afforded two kinds of pyrazoles,
namely 1-alkyl/aryl-5-ferrocenylpyrazoles (1,5-isomer) and 1-alkyl/aryl-3-
ferrocenylpyrazoles (1,3-isomer). In most cases, 1,5-pyrazole isomers have resulted
from these reactions as the single or the major product of the reactions. The
structures of 1-benzyl-5-ferrocenylpyrazole, 1-phenyl-5-ferrocenyl-pyrazole and 1-
(2-hydroxy-ethyl)-3-ferrocenylpyrazole were identified by X-ray single crystal
analysis. The analogous reactions between 3-phenylpropynal and hydrazinium salts
were also studied, which afforded 1-alkyl/aryl-5-phenylpyrazoles (1,5-isomer) and/or
v
1-alkyl/aryl-3-phenylpyrazoles (1,3-isomer). The regioselectivity of the reactions is
mainly governed by the nature of the substituents in hydrazine derivative.
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Waibel, Michael. "Design and Synthesis of Molecules to Probe Peptidase Activity." Lyon, École normale supérieure (sciences), 2008. http://www.theses.fr/2008ENSL0503.
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Une première partie décrit le développement d'inhibiteurs de la protéase VIH-1, qui possèdent une structure hydrazine urée. Nous avons développé une voie de synthèse efficace et convergente pour accéder à des composés énantiopurs à partir de deux "building blocks" : l'un est un dérivé d'acides aminés, l'autre peut être facilement obtenu à partir d'amines secondaires. Les composés ont ensuite été testés avec la protéase VIH-1 dans un test basé sur la technologie FRET. Dans une seconde partie, nous avons développé une sonde fluorogène pour la détection d'activités enzymatiques. Dans cette molécule, le fluorophore 2-(2'-hydroxyphenyl)-4(3h)-quinazolinone (HPQ) est couplé par un epaceur auto-effondrable avec une unité dipeptidique qui peut être clivée par une enzyme. Nous avons pu démontrer que le site de clivage dipeptidique est coupé par la leucyl aminopeptidase, ce qui conduit à un auto-effondrement rapide de l'epaceur, résultant dans la génération d'un signal fluorescentThe first part of this Ph. D thesis describes the development of several HIV-1 peptidase inhibitors having a hydrazino-urea core. We have developed an efficient, convergent synthetic route to enantiopure compounds generated from two independent building blocks, one derived from amino acids, the other one from easily accessible hydrazines. All compounds were tested with HIV-1 peptidase in a FRET based enzyme assay. In a second part, we have developed a fluorogenic probe for the detection of peptidolyic activity. In this molecule, the fluorophore 2-(2'-hydroxyphenyl)-4(3h)-quinazolinone (HPQ) is coupled via a self-immolative spacer to an amide function that can be cleaved by an enzyme. We could demonstrate that the amide group is cleaved by commercial leucyl aminopeptidase which leads to rapid fragmentation of the spacer unit resulting in the generation of an intensly fluorescent signal
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Anderson, Laura. "Design and Synthesis of Substituted 1,4-Hydrazine-linked Piperazine-2,5- and 2,6-diones and 2,5-Terpyrimidinylenes as α-Helical Mimetics." Scholar Commons, 2009. https://scholarcommons.usf.edu/etd/1830.
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The most common secondary structure of proteins is the alpha-helix. The alpha-helix can be involved in various protein-protein interactions (PPIs) through the recognition of three or more side chains along one face of the alpha-helix (Wells and McClendon, 2007). In recent years, there has been an increasing interest in the development of peptidic and non-peptidic compounds that bind to PPI surfaces. We focused on the design and synthesis of compounds that mimic the orientation of side chain residues of an alpha-helical protein domain. Although our scaffolds could potentially inhibit various PPIs, we focused mainly on the disruption of interactions among the Bcl-2-family of proteins and the Mdm-2-family of proteins to favor apoptosis in cancer cells.
A summary of Bcl-2 and Mdm-2 structure and function relationships that focuses on the possibility of using peptidic and non-peptidic alpha-helical mimics as PPI inhibitors is described in Chapter One. Chapter Two discusses the design and synthesis of 3-substituted-2,6- and 2,5-piperazinedione oligomers as more hydrophilic scaffolds compared to previously reported alpha-helical mimetics (Yin, et al., 2005). A key feature of this design is the linkage of the units by a hydrazine bond. While we were able to prepare several monomers containing the hydrazine linkage, synthesis of the dimers and trimers is very challenging. Due to the difficulty of synthesizing oligomeric piperazine-diones in practical yields, we next focused on the design and synthesis of novel 2,5-terpyrimidinylene scaffolds as an alternative to obtain alpha-helical mimetics; this is discussed in Chapter Three. The main outcome of this project was the efficient preparation of a "first-generation" non-peptidic compound library via a facile iterative synthesis enabled by the key conversion of 5-cyanopyrimidine to 5-carboxamidine. Chapter Three also discusses our progress towards the synthesis of structurally similar substituted-2,5-terpyrimidinylenes, but with more drug-like properties as determined by QikProp calculations. Chapter Four describes an independent study on the synthesis of a guanidine derivative as an alkylating agent for the synthesis of cysteine peptide nucleic acids, CPNA, which is another current project in our lab.
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Selby, Jonathan D. "Synthesis and reactivity of titanium hydrazido(2-) complexes." Thesis, University of Oxford, 2009. http://ora.ox.ac.uk/objects/uuid:afee94b7-7cd7-437c-8c31-1cba8a145720.
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This Thesis describes the synthesis and characterisation of titanium hydrazido(2-) complexes and their reactivity towards unsaturated molecules. Exploration of the bonding in titanium hydrazido(2-) complexes is performed through structural and computational studies. Chapter 1 introduces current Group 4 hydrazido chemistry and describes its relevance with comparison to Group 4 imido and mid/late metal hydrazido examples. Chapter 2 describes the synthesis and characterisation of new titanium hydrazido(2-) half-sandwich complexes. A general route to new titanium hydrazido(2-) chemistry is described and suppression of dimerisation pathways common to Group 4 alkyl hydrazido(2-) chemistry is investigated. Chapter 3 describes the synthesis, bonding and preliminary reaction chemistry of a new titanium hydrazido(2-) sandwich complex. Through structural and computational techniques, the bonding in the sandwich complex Cp2Ti(NNPh2)(py) (14) is explored and the implications to the reactivity of this complex considered. Chapter 4 describes the synthesis of new titanium hydrazido(2-) synthons which is extended to the synthesis of new titanium hydrazido(2-) complexes with diamide-amine type ligands. The bonding of the hydrazido(2-) ligand is explored through structural and computational study of these complexes. Chapter 5 describes the novel reaction chemistry of a diamide-pyridyl titanium hydrazido(2-) complex Ti(N2Npy)(NNPh2)(py) (23). Novel reactivity of both the Ti=Nα and Nα-Nβ bonds is presented with the mechanisms of some of these transformations probed by density functional theory (DFT) calculations. Chapter 6 presents full experimental procedures and characterising data for the new complexes reported. CD Appendix contains .cif files for all new crystallographically characterised complexes described.
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Weiss, Stephanie Tara. "The theoretical modeling, design, and synthesis of key structural units for novel molecular clamps and pro-apoptotic alpha helix peptidomimetics." [Tampa, Fla] : University of South Florida, 2006. http://purl.fcla.edu/usf/dc/et/SFE0001475.
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Cinar, Simge. "Synthesis Of Silver Nanoparticles And Cable Like Structures Through Coaxial Electrospinning." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/2/12611472/index.pdf.
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The aim of this study is to demonstrate the possibility of production of nanocables as an alternative to the other one dimensional metal/polymer composite structures like nanowires and nanorods. There is no certain definition of nanocableshowever they could be considered as assemblies of nanowires. Nanocable structure can be defined as a core-shell structure formed by a polymeric shell and a metal core that runs continuously within this shell. To produce nanocables, two main steps were carried out. Firstly, monodispersed silver metal nanoparticles to be aligned within the cable core were produced. Investigations on reduction reactions in the presence of strong and weak reducing agents and different capping agents revealed the importance of the kinetics of reduction in the production of monodispersed nanoparticles. Use of capping agents to give a positive reduction potential, resulted in the slow reduction rates that was critical for fine tuning of the final particle sizes between 1-10 nm. Hydrazine hydrate and oleylamine/ oleic acid systems were used as strong and weak reducing agents, respectively. By using weak reducing agent, monodisperse spherical silver nanoparticles with the diameter of 2.7 nm were produced. It was shown that particles with controlled diameter and size distribution can be obtained by tuning the system parameters. Secondly, particles produced as such were electrospun within the core of the polymer nanofibers and long continuous nanocables were produced. Polyvinyl pyrrolidone and polycaprolactone were used in shell part of nanocables. Transmission electron microscopy (TEM), scanning electron microscopy (SEM), photon correlation spectroscopy (PCS), X-ray diffraction (XRD) and surface plasmon resonance spectroscopy (SPR) analyses were carried out in order to understand the mechanism by which the nanoparticles were reduced and for further characterization of the product.
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Clements, Joseph Shelby II. "Synthesis of Insecticidal Mono- and Diacylhydrazines for Disruption of K+ Voltage-Gated Channels, and Elucidation of Regiochemistry and Conformational Isomerism by NMR Spectroscopy and Computation." Diss., Virginia Tech, 2017. http://hdl.handle.net/10919/77918.
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Based on the success of diacyl-tert-butylhydrazines RH-5849 and RH-1266 in controlling agricultural crop pests, we endeavored to synthesize our own diacylbenzyl- and arylhydrazine derivatives for use against the malaria vector Anopheles gambiae. In the process of producing a library of compounds for assay against An. gambiae, it became clear that employing regioselective acylation techniques (in molecules that feature two nucleophilic, acyclic nitrogen atoms α to one another) would be imperative. Synthesis of the library derivatives proceeded rapidly and after topical assay, we found three compounds that were more toxic than the RH-series leads. One of the three displayed an LD50 value of half that of RH-1266, though patch clamp assay concluded that toxicity was not necessarily linked to inhibition of mosquito K+ channel Kv2.1.
The acylation of monoarylhydrazines appears simple, but its regioselectivity is poorly understood when assumed as a function of basicity correlating to nucleophilic strength. We determined the ratio of the rate constants for distal to proximal N-acylation using 19F NMR spectroscopic analysis of reactions of 4-fluorophenylhydrazine with limiting (0.2 equiv) acylating agent in the presence of various bases. Acid anhydrides gave consistent preference for distal acylation. The selectivity of acylation by acyl chlorides when using pyridine gives strong distal preference, whereas use of triethylamine or aqueous base in conjunction with aroyl chlorides showed a moderate preference for proximal acylation. This observation yielded a convenient one-step method to synthesize proximal aroylarylhydrazines in yields comparable or superior to that provided by the standard three-step literature approach. Combined with NMR evidence of the distal nitrogen as the unambigiously stronger base of the two nitrogens, we propose a single electron transfer mechanism that predicts the regiochemistry of arylhydrazines toward acylating agents better than the nucleophilicity model based on pKa values.
While synthesizing the acylhydrazine library for assay against An. gambiae, NMR spectroscopy revealed rotational isomerisms of two types: chiral helicity (M)/(P) and acyl (E)/(Z)-isomerism due to hindered rotation. Variable temperature NMR allowed the measurement of N-N bond rotational barriers, as well as estimate the barrier of (E)/(Z) interconversion. We obtained the X-ray crystal structures of four diacylhydrazines to test this hypothesis and revealed both the twist conformation around the N-N bond axis and (E)/(Z)-isomerism around the proximal acyl group. Computation (which agreed with the crystal structures) allowed us to estimate which (E)/(Z)-isomers were most likely being observed in solution at room temperature by NMR spectroscopy. In addition, we were able to calculate transition structures corresponding to N-N bond rotational barriers of (E,Z)- and (Z,Z)-isomers of model molecules and rationalize the difference in coalescence temperatures between (E,Z)- and (Z,Z)-isomers.Ph. D.
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Tšubrik, Olga. "New methods in the synthesis of multisubstituted hydrazines /." Online version, 2006. http://dspace.utlib.ee/dspace/bitstream/10062/481/5/tsubrik.pdf.
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Cheaib, Khaled. "Synthesis, characterization and photochemical properties of 3d transition metal supported by aroyl-hydrazone ligands." Thesis, Strasbourg, 2013. http://www.theses.fr/2013STRAF062/document.
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Ce travail de thèse explorait certains aspects de la chimie de coordination de complexes moléculaires à bases de métaux 3d (Fe, Cu, Mn et Ni) supportés par des ligands azotés de type aroyle-hydrazone. Le travail de cette thèse était plus particulièrement centré sur le développement des nouveaux ligands et la photo chimie des complexes ferriques, afin d’élucider en particulier les mécanismes de la photo réduction qui valorise un brevet du laboratoire sur la production et le stockage d’énergie solaire via la photo réduction d’ions ferriques. Les complexes mis en jeu dans le processus ont été totalement caractérisés en solution et à l’état solide. Ce phénomène prend place en solution comme en solution gelée. La cinétique du processus photochimique a été suivie par UV-Visible comme par RPE. Cette photo réduction passe par un intermédiaire radicalaire et le solvant joue le rôle du donneur des électrons. Ce processus a été totalement étudié : l’effet du solvant, l’effet de la modification dans la sphère de coordination du complexe, l’effet de la modification de la périphérie des ligands et finalement l’effet des longueurs d’ondes. D’autres domaines sont également explorés, comme le magnétisme moléculaire ou encore la catalyse homogène (oligomérisation de l’éthylène) avec des complexes à base de Ni2+This PhD thesis explored some aspects of the coordination chemistry of molecular complexes based on 3d transition metal ions (Fe, Cu, Mn and Ni) coordinated by multidentate aroyl-hydrazone ligands. The work of this thesis was particularly focused on the development of new ligands, their coordination chemistry and the photochemistry of ferric complexes. The central objective of this work was to elucidate the mechanism of the photo reduction process, in order to valorize an already accepted laboratory patent on the production and storage of solar energy. The complexes involved in the process have been fully characterized in solution and in the solid state. This phenomenon takes place in solution as in frozen solution. The kinetics of the photochemical process was followed by UV-Visible as by RPE. This photo reduction passes through a radical intermediate and the solvent plays the role of the electron donor. This process has been fully studied: the effect of the solvent, the effect of the modification in the coordination sphere of the complex, the effect of the modification of the periphery of the ligands and finally the effect of the light and different wavelengths. Other fields are also explored, such as molecular magnetism for different mono and dinuclear iron and manganese complexes or even homogeneous catalysis (oligomerization of ethylene) with complexes based on Ni(II)
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Yi, Sung Wook. "Cysteine Based PNA (CPNA): Design, Synthesis and Application." [Tampa, Fla] : University of South Florida, 2008. http://purl.fcla.edu/usf/dc/et/SFE0002346.
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Marques, de Oliveira Paulo Filho. "Investigation of mechanochemical synthesis of condensed 1,4-diazines and pharmaceutically attractive hydrazones." Thesis, Ecole nationale des Mines d'Albi-Carmaux, 2015. http://www.theses.fr/2015EMAC0007/document.
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L'un des objectifs des industries chimique et pharmaceutique est de développer des procédés verts évitant ou réduisant l'utilisation de solvants. Mais ne pas utiliser de solvant nécessite souvent des catalyseurs métalliques ou autre, ce qui rend les purifications délicates, comme dans le cas des synthèses de chimie fine permettant l'obtention de principes actifs pharmaceutiques. C'est ainsi que la mécanochimie a émergé en tant que voie durable pour la synthèse chimique, y compris dans le cas des transformations moléculaires organiques sous contrainte mécanique. Malgré les progrès récents de cette méthodologie, certains aspects de l'action mécanique ne sont pas totalement élucidés, en particulier ce qui concerne les mécanismes. Dans cette thèse, trois axes principaux de la mécanochimie ont été explorés. Dans une première partie, le mécanisme moléculaire de la synthèse de deux types de 1,4-diazines, la dibenzo[a,c]phenazine (DBPZ) et la 2,3-diphenylquinoxaline (DPQ), a été investigué. La RMN 13C CP-MAS a permis de mettre en évidence des intermédiaires de cette synthèse, et des mesures calorimétriques ont révélé que deux réactions se poursuivaient après broyage. La possibilité d'une réaction concertée a également été prise en compte dans le cas de la dibenzo[a,c]phenazine. La seconde partie concerne la formation de la 2,3-diphenylquinoxaline. Les paramètres du procédé ont été étudiés, dans le cas d'un broyeur à bille vibrant. L'influence des matériaux de broyage, de la taille et de la masse des billes, la granulométrie des matières premières, ainsi que la température des media de broyage ont été étudiés, permettant de déterminer une énergie d'activation apparente (Ea). Le tracé des courbes selon Arrhenius et Eyring-Polanyi a montré des changement de Ea caractéristiques de modifications au niveau du mécanisme, attribuées à l'apparition d'un possible eutectique fondant au dessus de 30°C, induit mécaniquement. Après cette étude qui a permis la compréhension de certains points fondamentaux, et d'approfondir les procédés de ces réactions modèles, une troisième partie traite de l'application de la mécanochimie à la synthèse en phase solide d'hydrazones d'intérêt pharmaceutique, et à celle catalysée de dérivés de l'isoniazide obtenus par réaction d'aldéhydes et d'hydrazines. D'une manière générale, les durées de réaction sont plus faibles, et les rendements meilleurs, qu'avec les méthodes classiques. L'influence des réactivités électronique et des hydrazines à l'état solide a été discutée. Les essais biologiques ont démontré une activité avérée des dérivés de l'isoniazide dans l'inhibition de Mycobacterium tuberculosis. Les résultats présentés dans cette thèse englobent plusieurs aspects très complémentaires de la mécanochimie. L'approche fondamentale du mécanisme est d'un accès difficile, en raison de la complexité du système, mais des avancées ont été réalisées comme la mise en évidence d'intermédiaires à longue durée de vie. Les paramètres du procédé apportent une contribution à la compréhension du mécanisme mais aussi en vue du scaling-up. Enfin, la mécanosynthèse s'est révélée être une méthode de chimie verte particulièrement adaptée à la synthèse d'hydrazones d'intérêt pharmaceutique, pour le screening de nouvelles entités ou la synthèse durable de produits de grande puretéOne of the goals of pharmaceutical and chemical industries is the development of green processes that eliminates or reduces the use of solvents. However, avoiding solvents often requires the use of metal catalysts or others, that accelerates chemical reactions, but make the purifications difficult, especially in the case of fine chemical products, such as active pharmaceutical ingredients. The mechanochemistry has emerged as a sustainable way that enables chemical synthesis, including organic molecular transformations, using the mechanical energy. In spite of the recent advances of the methodology, some aspects of the mechanical action still remain to be fully elucidated, mainly concerning the mechanisms. In this thesis, three main axes of mechanochemistry were explored. First, the molecular mechanism of 1,4-diazine mechanosynthesis, mentioning dibenzo[a,c]phenazine (DBPZ) and 2,3-diphenylquinoxaline (DPQ), is investigated by using 13C CP-MAS NMR that reveals intermediate species for DBPZ, and by calorimetric measurements that show continuation of the reaction after grinding for both reactions. The possibility of a concerted mechanism is considered for dibenzo[a,c]phenazine case. The second focus is on 2,3-diphenylquinoxaline product formation. The process parameters for a vibratory ball mill were studied. Grinding material, size and mass of the balls, granulometry of the starting material were assessed, as well as the temperature of the milling media, providing apparent activation energy (Ea). Arrhenius and Eyring-Polanyi plots presented changes in Ea indicating changes in mechanism, which was attributed to a possible mechanically induced eutectic melting after 30°C. Finally, after understanding some fundamentals and processes for those model reactions, the mechanochemical route was successfully applied to solid-state synthesis of pharmaceutically attractive phenolic hydrazones and catalyzed isoniazid derivatives synthesis, by reacting solid aldehydes and hydrazines. In general, the products were obtained in shorter times and in higher yields compared to classical thermal route. The roles of electronic and solid-state reactivity of the hydrazines were discussed. Biological assays demonstrated the great activity of isoniazid derivatives in inhibiting Mycobacterium tuberculosis. The results presented here cover the mechanochemistry at different levels. The fundamental comprehension is still difficult to access due to the complexity of the system, but some advances could be made such as the detection of intermediate species with significant lifetime. The process parameters are equally important to deduce some mechanism, but also for scale up purposes. At last, the mechanosynthesis of hydrazones showed to be a greener route to produce pharmaceuticals, for high screening of new ones, as well as for the synthesis of others, with great purity and waste reduction
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Perry, Matthew William Dampier. "Synthetic applications of hydrazones." Thesis, University of Oxford, 1985. http://ora.ox.ac.uk/objects/uuid:5009520c-850a-4030-a8b2-2245b4abe264.
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This thesis describes investigations of reactions of hydrazones and their N-anions via the imino carbon atom; these reactions show umpolung reactivity. The conversion of the derived azo products into synthetically useful compounds (e.g. 4-ketoesters, 4-ketoacids, 4-ketonitriles, alkanes, amines) is also described. Reactions of ṯ-butylhydrazone anions with enoic esters are described. 4-ṯ-Butylazoesters were formed on reaction with methyl crotonate. The 4-ṯ-butylazoesters derived from aldehyde ṯ-butylhydrazones were converted by tautomerisation of the azo function and hydrolysis of the resultant ṯ-butylhydrazone to 4-ketoesters or 4-ketoacids in 47-60% yield. Other Michael type electrophiles investigated gave negligible yields of C-adducts. ṯ-Butylhydrazones of aliphatic aldehydes were found to give ene adducts with methyl acrylate or aerylonitrile on reflux in xylene for 24h. The resultant azo compounds were converted into 4-ketoesters (75-90%) or 4-Ketonitriles (18- 75%) by tautomerisation and hydrolysis. Other potential enophiles investigated did not give C-adducts. A synthesis of a ṯ-butylazoalkene from an aldehyde ṯ- butylhydrazone and benzaldehyde by addition and dehydrative elimination is described. The reduction of ṯ-butylazoalkenes with zinc-acetic acid is described. The C-alkylation of tritylhydrazone anions with alkyl halides gave tritylazoalkanes. Tritylazoalkanes decomposed by homolytic fragmentation with dinitrogen evolution above -20°C. Trapping with ethanethiol of the resultant radicals gave alkanes in 27-69% yield. The last section describes investigations of the anions of various secondary alkyl hydrazones for C-reaction, and attempted reduction of the resultant azoalkanes to amines Isopropyl- and cyclohexylhydrazones gave low yields of Cadducts. 2,4-Dimethylpent-3-yl- (DMP) and 3,3-dimethylbut- 2-ylhydrazones (TBM) gave good yields of C-adducts. Direct reduction of the azoalkanes to amines was not achieved Azoalkanes derived by alkylation of ketone DMP or TBM hydrazones were tautomerised and hydrolysed to hydrazines in low yield. Reduction of a so-formed hydrazine gave an amine, but in low overall yield (14%).
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Tiong, Pei Jen. "Synthesis and reactivity of new titanium hydrazido complexes." Thesis, University of Oxford, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.559841.
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This Thesis describes the synthesis and characterisation of titanium hydrazido(2-) and alkylidene hydrazido(2-) complexes and their reactivity towards unsaturated molecules. Exploration of the bonding in titanium hydrazido(2-) and alkylidene hydrazido(2-) complexes is performed through structural and computational studies. Chapter 1 introduces current Group 4 hydrazido chemistry in comparison to Group 4 imido and mid/late metal hydrazido examples. Current Group 4 alkylidene hydrazido chemistry is also described. Chapter 2 describes the synthesis, bonding and the novel reaction chemistry of titanium hydrazido(2-) half-sandwich complexes. Novel reactivity at the Ti=N, bond is presented with the mechanisms of some of these transformations probed by Density Functional Theory (DFT) calculations. Chapter 3 describes the novel reaction chemistry of Cp*Ti{MeC(Nipr)2} (NNMe2) in comparison to its imido and diphenyl hydrazido analogues. Novel reactivity at both Ti=N, and Na-N~ bonds is presented with the mechanisms of some of these transformations probed by Density Functional Theory (DFT) calculations. Chapter 4 describes the synthesis and characterisation of a new titanium alkylidene hydrazido(2-) complex. The bonding of the alkylidene hydrazido(2-) ligand is explored through structural and computational studies. Novel reactivity at Ti=N, and Na-N~ bonds is presented. Chapter 5 presents full experimental procedures and characterising data for the new complexes reported. CD Appendix contains .cif files for all new crystallographically characterised complexes described.
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Moore, Peter Robert. "Organic synthesis through radical cyclisation reactions." Thesis, University of Exeter, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337802.
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Houghton, Ralph Warren. "Synthesis of 1-substituted phenyl phthalazines." Scholarly Commons, 1990. https://scholarlycommons.pacific.edu/uop_etds/2201.
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The purpose of this work was the preparation of a new class of arylhydrazone reagents. When combined with a mixture of ketones and aldehydes, these new reagents would give derivatives different from those given by current arylhydrazone reagents. These derivatives could be separated by crystallization or chromatography and could then be easily characterized by x-ray crystallography or nuclear magnetic resonance (NMR).
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Schofield, Daniel. "The synthesis and reactivity of Group 4 metal hydrazides." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:8eb27904-237b-4065-ad37-6008166731e9.
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This thesis describes the synthesis, characterisation and reactivity of diamide-amine and bis(cyclopentadienyl) supported Group 4 hydrazido(2-) compounds towards unsaturated molecules. The mechanisms of these transformations are probed using a range of structural, kinetic and computational methods.
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Banerjee, Sanjukta. "Titanium-catalyzed additions of substituted hydrazines to alkynes catalyst design, mechanistic studies, and applications in heterocycle synthesis /." Diss., Connect to online resource - MSU authorized users, 2008.
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Laniel, Dominique. "Synthèse de polymères d'azote par pression comme matériaux énergétiques du futur." Electronic Thesis or Diss., Sorbonne université, 2018. http://www.theses.fr/2018SORUS472.
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L’objectif de cette thèse doctorale fut la synthèse de composés polyazotés qui serviraient comme matériaux énergétiques du futur. Afin d’y arriver, les propriétés physico-chimiques de l’azote pur ainsi que des mélanges binaires xénon-azote, hydrogène-azote ainsi que lithium-azote furent étudiés à des pressions et températures extrêmes. Lors de la compression de l’azote pur jusqu’à environ 250 GPa et chauffé à 3300 K, une nouvelle forme d’azote polymérique constituée d’anneaux N6 interconnectés fut obtenue. À basse pression, les études du mélange Xe-N2 permirent de découvrir un composé de van der Waals de stoechiométrie Xe(N2)2. À plus haute pression et température (150 GPa et 2500 K) un solide composé de xénon et d’azote simplement lié fut obtenu. L’étude du système N2-H2 se focalisa sur le composé N2(H2)2. Sa structure complexe fut déterminée et, une réaction chimique vers 50 GPa ayant comme produit de réaction des azanes (NxHx+2) fut mise à jour. Il fut constaté que l’azane ammoniac (NH3), principalement obtenu, se transforme en hydrazine (N2H4)—pourtant a priori moins stable thermodynamiquement—lors de la décompression des échantillons réagit. Enfin, l’étude du système Li-N2 révéla une chimie remarquable entre ces deux éléments. Une grande variété d’anions d’azote fut obtenue, notamment N3-, [N2]~2 [N2]~1 et N5-. En particulier, le pentazolate de lithium (LiN5), contenant l’anion pentazolate hautement énergétique, put être récupéré aux conditions ambiantes. Ce composé est le premier composé polyazoté à haute densité d’énergie produit par pression et récupéré aux conditions ambiantes, démontré le potentiel des synthèses hautes pressions pour ce type de matériauThe goal of this thesis is to synthesize novel polynitrogen compounds by pressure as the next-generation high energy density materials (HEDM). To achieve this, the physico-chemical properties of pure nitrogen as well as the xenon-nitrogen, hydrogen-nitrogen and lithium-nitrogen mixtures were studied under extreme pressure and temperature conditions. In the case of the compression of pure nitrogen, a novel polymeric nitrogen solid composed of interconnected chains of N6 rings was produced at 250 GPa and 3300 K. The low pressure Xe-N2 investigation revealed the formation of a stoichiometric Xe(N2)2 van der Waals compound. Above 150 GPa and 2500 K a xenon-polynitrogen material was observed. The N2-H2 study, focusing on the characterization and high-density behavior of the N2(H2)2 van der Waals compound, uncovered its pressure-induced chemical reaction near 50 GPa into azanes (NxHx+2), with ammonia (NH3) as the main constituent. Intriguingly, decompression of the reacted sample resulted, below 10 GPa, in the transformation of ammonia into its thermodynamically less stable counterpart hydrazine (N2H4). Lastly, the Li-N2 system proved to be of great interest due to the large array of anionic nitrogen moieties discovered (N3-, [N2]~2 [N2]~1 and N5-). In particular, lithium pentazolate (LiN5), containing the elusive energetically-rich pentazolate anion, was synthesized above 45 GPa and 2500 K. Moreover, it could be retained down to ambient conditions. It is the first polynitrogen HEDM produced by high pressure and retrieved down to ambient conditions. These results demonstrate the potential of high pressure for the synthesis of industrially relevant HEDM
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Kirchhoff, Jan Hendrik. "Totalsynthese von (+)-2-epi-Deoxoprosopinin und neue Hydrazin-Harze für die organische Festphasensynthese." [S.l.] : [s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=96284697X.
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Vilionskienė, Ingrida. "Krūvius transportuojančių, stabilios amorfinės būsenos hidrazonų, azinų bei antrachinono darinių sintezė ir savybės." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2005. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2005~D_20050726_104916-89724.
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The aims of the work were as follows: • synthesis of branched dimers with stable amorphous state possessing tiophenylsulphide, sulphide and hydroxygroups in the linking fragment of chromophores from aromatic and heteroaromatic alde6 hyde phenylhydrazones. A thorough study of physical and optoelectrographic properties of these charge-transporting compounds; • synthesis of new crosslinkable charge transporting molecular glasses exhibiting high charge carrier mobilities, high morphological stability; • design and synthesis of new hole transporting molecular glasses and polymers (from 9-(2,3-epoxypropyl)carbazole); • investigation of the interaction of 1(2)-aminoanthraquinone and 1- chloro-2,3-epoxypropane (CEP) with the aim to use the products for the creation of hydroxygroups possessing electron-transporting materials, having stable amorphous state.
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ZIMMERMANN, DIANE. "Modulation de la synapse glutamatergique : conception et synthese d'analogues de molecules neuroactives ; applications cardio-vasculaires (doctorat : pharmacochimie)." Strasbourg 1, 1999. http://www.theses.fr/1999STR15008.
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Gamero-Vega, Karen Yazmin. "Synthesis and reactivity studies of Group 5 imido and hydrazido complexes." Thesis, University of Oxford, 2018. http://ora.ox.ac.uk/objects/uuid:86a06f8a-9f96-426b-a1b0-96cd2f20e3cc.
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This Thesis describes the synthesis and reactivity of Group 5 imido and hydrazido complexes with tridentate, trianionic ligands. Various synthetic routes towards these hydrazido compounds were explored and in which several intermediates were synthesised and their chemistry was explored. The reactivity of the imido and hydrazido complexes with unsaturated and other small molecules was also studied. Chapter One provides a general introduction to tridentate pincer and tripodal ligands. The structure, synthesis and reactivity of Group 4 and 5 imido and hydrazido complexes is also reviewed. Chapter Two describes three different synthetic routes towards tantalum hydrazido complexes with tridentate, trianionic ligands. Synthesis, characterization and bonding analysis of the precursor dichloride species Ta(NN2SiMe3)Cl2, which is used as starting material for two of the synthetic routes, is also described. The synthesis, characterization and bonding analysis of the tantalum dialkyl and alkyl-amido precursors prepared in the multistep route is also explored. Chapter Three describes the synthesis and characterisation of Group 5 imido complexes with tridentate, trianionic ligands of the type Li3(NN2R) and Li3(NNNSiMe3). Reactivity studies of the imido complex Nb(NN2iPr)(NtBu)(py)2 with unsaturated and other small molecules are also explored. Chapter Four describes the synthesis and characterisation of Group 5 hydrazido complexes with tridentate, trianionic ligands by two different synthetic routes, alongside a bonding analysis of the imido compounds M(NN2R)(NtBu)(py)2 and their hydrazido analogues M(NN2R)(NNPh2)(L)x. Reactivity studies of the hydrazido complex Nb(NN2iPr)(NNPh2)(py)2 with unsaturated and other small substrates are also described. Chapter Five presents full experimental procedures and characterising data for the new methodologies and complexes reported in this Thesis.
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Yazici, Ceyda. "Synthesis Of 4-iodopyrazole Derivatives." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/3/12609750/index.pdf.
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Pyrazoles have been studied for over a century as an important class of
heterocyclic compounds and continue to attract considerable interest due to the
broad range of biological activities they possess. The electrophilic cyclization of
the acetylenic hydrazones initiated by molecular iodine could provide new ways of
synthesizing biologically active 4-iodopyrazole derivatives, which are important
precursors for the synthesis of highly substituted pyrazole derivatives. For this
reason, we investigated the synthesis of 4-iodopyrazole derivatives, such as 1-aryl-
5-alkyl/aryl-4-iodopyrazoles, starting from phenylhydrazine and ,-acetylenic
aldehyde derivatives. Initially, ,-acetylenic aldehydes were synthesized by
formylation reaction of corresponding alkynes with DMF. Then, hydrazone
derivatives of these aldehydes were prepared by heating them with
phenylhydrazine in a neat manner at 55 °C for 5 h. Finally, acetylenic phenyl hydrazone derivatives were subjected to electrophilic cyclization by treating with excess molecular iodine at 80 °
C for 3 h. Although electrophilic cyclization is commonly used in organic chemistry, it has not been employed for the cyclization of acetylenic phenyl hydrazones to pyrazole derivatives. Under optimized conditions, these reactions afforded 1-aryl-5-alkyl/aryl-4-iodopyrazole derivatives in moderate to good yields as the single or the major product of the reactions. In some cases, 1-aryl-5-alkyl/arylpyrazole derivatives resulted from these reactions as minor products. In conclusion, 4-iodopyrazole derivatives were synthesized for the first time directly from acyclic starting materials, ,-acetylenic phenylhydrazones and iodine, via electrophilic cyclization.
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Groom, Laura R. "Synthesis and reactions of titanium-nitrogen multiple bonds." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:17286f91-a1d9-48dc-baf3-02fbbe30a314.
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This Thesis reports the synthesis and reactions of new hydrazide, alkoxyimide and benzimidamide complexes (L)Ti=NX (X = NAr2, NOtBu or C(Ar)NOtBu; L = dianionic supporting ligand or ligand set). The work is supported by DFT calculations which are used to rationalise the reaction outcomes observed and, in one case, the bonding in alkoxyimide complexes. Chapter One provides a background to hydrazide complexes, starting with their relevance to nitrogen fixation. In addition, Group 4 imide, alkylidene hydrazide and alkoxyimide complexes are also reviewed. The Chapter focuses in particular on the synthesis, structure, and stoichiometric and catalytic reactions of these complexes with unsaturated substrates. Chapter Two describes the development of the virtually unexplored 1,2-diamination reaction. The substrate scope and isolation of the vinylamine products are discussed. The protonation of the vinylimide complex Ti(N2NMe){NC(Ph)C(Me)NPh2}(py) and the overall diamination reaction itself is then explored through an in-depth experimental and computational study. Chapter Three details the synthesis of cyclopentadienyl-amidinate supported alkoxyimide complexes. The first detailed reactivity study, supported by structural and computational studies, of any alkoxyimide complex is reported. Novel reactivity at Ti=Nα and, in one instance, Nα–Oβ reductive bond cleavage is observed. Chapter Four describes the reactivity of the benzimidamide complex Cp*Ti{PhC(NiPr)2}{NC(ArF5)NOtBu} with a range of substrates including heterocumulenes, aldehydes, isonitriles and B(ArF5)3. Novel reactivity at Ti=Nα, and 3-component coupling is presented, and the experimental results supported by structural and computational studies. Chapter Five presents full experimental procedures and characterising data for the new complexes reported.
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Cebrowski, Pamela H. "Application of Cope-type hydroamination in the synthesis of hydrazones and the total synthesis of the benzyltetrahydroisoquinoline norreticuline." Thesis, University of Ottawa (Canada), 2009. http://hdl.handle.net/10393/28052.
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The hydroamination of alkenes and alkynes is a highly desirable, yet underdeveloped approach to nitrogen incorporation into molecules. Currently, this approach is predominantly limited to transition metal catalysis and suffers from limitations in substrate scope and functional group compatibility. The focus of thesis is the development of simple, metal-free hydroaminations through a different approach that is concerted in nature: the Cope-type hydroamination (eq. 1).
This transformation was applied towards the intermolecular hydroamination of alkynes with hydrazines, and is regioselective for the linear, "anti-Markovnikov" isomer 5 (eq. 2) and is presented in Chapter 2. This methodology has also been applied to intramolecular cyclizations and has been extended towards the synthesis of natural products with a specific focus on the challenging formation of 6-membered rings. The total synthesis of the benzyltetrahydroisoquinoline alkaloid norreticuline 8 through a Cope-type hydroamination key step (eq. 3) is presented in Chapter 3.
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Dilek, Özlem. "Synthesis and spectroscopic characterization of fluorescent boron dipyrromethene (BDP) probes for site specific bioorthogonal labeling of proteins." Diss., Online access via UMI:, 2009.
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Karahan, Dag Fulya. "Synthesis Of 5-ferrocenyl-4-((4-nitrophenyl)sulfenyl)-1h-pyrazoles By Electrophilic Cyclization." Master's thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613443/index.pdf.
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Pyrazoles have been intensely studied in the design and synthesis of biologically active agents because they display considerable medicinal activities. Recent studies have shown that integration of a ferrocenyl unit with structural features of pyrazoles can result in the formation of the new products with enhanced or/and unexpected biological activity since several ferrocene derivatives have already been illustrated to be active against a number of tumors. Therefore, we have investigated the electrophilic cyclizations of the hydrazones to afford 5-ferrocenyl-4-((4-nitrophenyl)sulfenyl)-substituted pyrazole derivatives. First, the requisite hydrazone derivatives were synthesized by the reactions of ferrocenyl propargyl aldehydes or ketones with a series of hydrazines. Then electrophilic cyclizations of these hydrazones were investigated by treating with 4-(nitrophenyl)sulfenyl chloride as electrophile. By employing these electrophilic cyclizations, a series of 5-ferrocenyl-4-((4-nitrophenyl)sulfenyl)-1H-pyrazoles, 5-ferrocenyl-4-((4-nitrophenyl) sulfenyl)-3-methyl-1H-pyrazoles and 5-ferrocenyl-4-((4-nitrophenyl)sulfenyl)-3-phenyl-1H-pyrazoles have been synthesized in moderate to good yields.
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Judele, Roxana Daniela. "Synthese und Eigenschaften von langkettig substituierten Azamakrozyklen-Metall-Komplexen und Hydrazidestern." Göttingen Sierke, 2007. http://d-nb.info/986056391/04.
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Khan, Azra Nasir. "Novel solid-phase strategies for the synthesis of polyamines and atypical peptides." Thesis, University of Nottingham, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.311758.
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Budreckienė, Rūta. "Funkcines grupes turinčių elektroaktyvių junginių sintezė ir tyrimas." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2005. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2005~D_20050719_153120-62132.
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黃友民 and Youmin Huang. "NMR spectroscopic and kinetic studies on secondary enamines of heterocyclic oximes hydrazones and semicarbazones." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1991. http://hub.hku.hk/bib/B31232243.
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Gormen, Meral. "Synthesis Of Ferrocenyl Substituted Pyrazoles." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/3/12606358/index.pdf.
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Pyrazoles have been studied for over a century as an important class of heterocyclic compounds and continue to attract considerable interest due to the broad range of biological activities they possess. The incorporation of the essential structural features of pyrazoles with a ferrocene moiety could provide new derivatives with unexpected and/or enhanced biological activities since several ferrocene derivatives have already been shown to be active against a number of tumors. For this reason, we investigated the synthesis of ferrocenyl-substituted pyrazoles, such as 1-alkyl/aryl-5-ferrocenylpyrazoles, by employing the reaction between (2-formyl-1-chlorovinyl)ferrocene and hydrazine derivatives. Although this reaction is known, it was not studied in much detail and the low yields of ferrocenyl pyrazoles were obtained. Thus, we have reinvestigated this reaction and improved the yields of pyrazoles by optimizing the reaction conditions. (2-Formyl-1-chloro vinyl)ferrocene was first reacted with the excess amount (3 equivalents) of hydrazine derivative at 25 0C in dioxane under argon for 2 hours, and the resulting mixture was then heated at 100 0C for 6 hours in the same solvent. Under our optimized conditions, these reactions afforded 1-alkyl/aryl-5-ferrocenylpyrazole derivatives in moderate to good yields as a single or major product of the reaction. In some cases, 1-alkyl/aryl-3-ferrocenylpyrazole derivatives resulted from these reactions as very minor products.
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Srisailam, Shravan Kumar. "Synthesis, structural characterization and reactivity of homo- and heterobimetallic imidoalanes and carbaalanes, aluminum hydrazide and aluminum peroxide compounds." Doctoral thesis, [S.l.] : [s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=974568724.
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Mingle, David, and Abbas Shilabin. "SYNTHESIS OF PYRROLO[2,1-c] [1,4] BENZODIAZEPINE -11- HYDRAZINYL DEVRIVATIES AS A POTENTIAL ANTIMICROBIAL AGENT." Digital Commons @ East Tennessee State University, 2018. https://dc.etsu.edu/asrf/2018/schedule/130.
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SYNTHESIS OF PYRROLO[2,1-c] [1,4] BENZODIAZEPINE -11- HYDRAZINYL DEVRIVATIES AS A POTENTIAL ANTIMICROBIAL AGENT
David Mingle and Abbas G. Shilabin Department of Chemistry, East Tennessee State University, Johnson City, TN 37614, USA
ABSTRACT Pyrrolo [2,1-c] [1,4] benzodiazepine (PBD) is a class of natural products obtained from various actinomycetes which have both anti-tumor and antibiotic activities. They can bind to specific sequences of DNA that can trigger a biological response which is of pharmacological interest. PBD can also prevent cell division leading to death of the bacteria. This research focuses on the synthesis of novel PBD-11-hydrazinyl derivatives using a multi step synthesis. PBD-dilactam was initialy produced using isatoic anhydride and (S)-proline which was then converted to the PBD-thiolactam using Lawesson's reagent. Reaction of thiolactam with hydrazine in ethanol afforded PBD-11-hydrazinyl in good yield. Condensation of PBD-11-hydrazinyl with aldehydes possessing various substitutions was performed to generate (S,E)-11-[2-(phenylmethylene)hydrazono]-1,2,3,10,11,11a-hexahydro-5H-benzo[e]pyrrolo[1,2-a][1,4]diazepin-5-one. 1H-NMR , 13C-NMR , DEPT and GC-MS were used to characterize the products. Inhibition activity of the products were carried out using TEM-1 and p99 β-lactamases. Microbial activity will be conducted in collaboration with Natural Product Center at University of Mississippi on the final products.
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Davis, Randon Emerson. "Development and Synthesis of 7-Alkylguanosine Pronucleosides for Application in Chemical Solid-State Oligoribonucleic Acid Synthesis." Kent State University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=kent1595274318375068.
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Breuer, Irene. "Asymmetrische Synthese von Sordidin, 7-epi-Sordidin und von Polyoleinheiten mit quartären Stereozentren." Aachen : Mainz, 2005. http://deposit.d-nb.de/cgi-bin/dokserv?idn=976668076.
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Mellino, Simona. "Synthetic and computational studies of group 3 and group 4 imido and hydrazido compounds." Thesis, University of Oxford, 2017. https://ora.ox.ac.uk/objects/uuid:dcf036ac-263d-4c62-967c-c807fe1fe61e.
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This Thesis describes the synthesis and reactivity of titanium-nitrogen multiply bonded compounds. Mechanistic and bonding studies on titanium imido, hydrazido and borylimido complexes as well as on a novel scandium borylimide recently reported in our research group were described. Chapter 1 provides an introduction to Group 4 and Group 3 metal-nitrogen multiply bonded compounds including synthesis, bonding and reactivity of titanium imido, hydrazido, alkylidene hydrazido and borylimido complexes, (L)Ti=NR, (L)Ti=NNR2, (L)Ti=NNCR2 and (L)Ti=NBR2. Chapter 2 describes the reactions of the hydrazido compound Ti(N2 iPrNMe)(NNPh2)(py) with the Si - H and B - H bonds of silanes and boranes and with H2. The nature and mechanism of these reactions were investigated both computationally and experimentally. Chapter 3 explores a series of new reactions and unprecedented transformations of organic boranes and silanes with titanium half-sandwich compounds. In addition, detailed mechanistic work, using DFT calculations, was performed to understand the chemistry behind these reactions. Chapter 4 describes the bonding and reactivity of novel borylimido compounds. The systematic approach recently implemented in our research group to synthesise new titanium borylimido compounds, is described. A full computational study of the bonding of compounds with sandwich and half-sandwich structures is explained in detail. Chapter 5 explores the experimental attempts to isolate the first scandium borylimido complex performed in our group. DFT and QTAIM and detailed mechanistic study are presented. Chapter 6 contains experimental details, characterising data and DFT energies and coordinates of the optimized structures for the chemistry presented in Chapters Tw-Five.
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Huang, Shih-huang. "Synthetic, Mechanistic, and Structural Studies of Polynuclear Metal Clusters and Hydrazido-Substituted Tantalum(V) Compounds." Thesis, University of North Texas, 2010. https://digital.library.unt.edu/ark:/67531/metadc33166/.
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A combined experimental and computational study on the reversible ortho-metalation exhibited by the triosmium cluster Os3(CO)10(dppm) (dppm = 1,1-bis(diphenylphosphino)methane is reported. The conversion of nonacarbonyl cluster HOs3(CO)9[-PhP(C6H4)CH2PPh2] to Os3(CO)10(dppm) is independent of added CO and exhibits a significant inverse equilibrium isotope effect (EIE). Reductive coupling of the C-H bond in HOs3(CO)9[-PhP(C6H4)CH2PPh2] leads to the formation of agostic C-H and two distinct aryl-π species prior to the rate-limiting formation of the unsaturated cluster Os3(CO)9(dppm). Heating the unsaturated dimer H2Re2(CO)8 with Cp*Rh(CO)2 (Cp* = 1,2,3,4,5-pentamethylcyclopentadiene) at elevated temperature affords the new trimetallic clusters H2RhRe2Cp*(CO)9 and HRh2ReCp*2(CO)6, and the spiked-triangular cluster HRhRe3Cp*(CO)14. H2Re2(CO)8 reacts with Cp*2Rh2(CO)2 under identical conditions to furnish H2RhRe2Cp*(CO)9 and HRh2ReCp*2(CO)6 as the principal products, in addition to the tetrahedral cluster H2Rh2Re2Cp*2(CO)8. H2RhRe2Cp*(CO)9 undergoes facile fragmentation in the presence of halogenated solvents and the thiols RSH (where R = H, C6H4Me-p) to afford the structurally characterized products Cp*Rh(-Cl)3Re(CO)3, S2Rh3Cp*(CO)4, Cp*Rh(-Cl)(-SC6H4Me-p)2Re(CO)3, and Cp*Rh(-SC6H4Me-p)3Re(CO)3. The new hydrazido-substituted compounds TaCl(NMe2)3[N(TMS)NMe2] (TMS = tetramethylsilyl) and Ta(NMe2)4[N(TMS)NMe2] have been synthesized and their structures established by X-ray crystallography. The latter product represents the first structurally characterized octahedral tantalum(V) complex containing a single hydrazido(I) ligand in an all-nitrogen coordinated environment about the metal center. The fluxional properties of the amido and hydrazido ligands in these new compounds have been established by VT 1H NMR spectroscopy (VT = variable temperature). Preliminary data using Ta(NMe2)4[N(TMS)NMe2] as an ALD (ALD = atomic layer deposition) precursor for the preparation of tantalum nitride and tantalum oxide thin films are presented.
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Ollivier, Anthony Gabriel André. "Synthèse asymétrique de spiroacétals : vers la broussonétine H." Thesis, Clermont-Ferrand 2, 2011. http://www.theses.fr/2011CLF22109/document.
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Le motif spiroacétal est une structure présente dans le squelette de nombreuses molécules naturelles possédant des activités biologiques variées et pour laquelle il existe de nombreuses voies de synthèse. En revanche, son analogue azoté, le motif spiroaminal a été beaucoup moins étudié. Le premier de nos objectifs a consisté à développer une voie de synthèse énantiosélective, la plus générale possible, de ce motif. La stratégie retenue repose sur une étape clé de spirocyclisation acido-catalysée d’aminohydroxycétones issues de l’alkylation séquentielle de l’acétone N,N-diméthylhydrazone par divers synthons iodés. Si les spiroaminals attendus n’ont pas pu être obtenus, ces cétones polyfonctionnalisées ont permis d’accéder efficacement à des spiroacétals originaux : les 1,6-dioxaspiro [4.6] undécanes et les 1,7-dioxaspiro [5.6] dodécanes. Dans une deuxième partie de notre travail, nous nous sommes intéressés à la synthèse totale de la broussonétine H, spiroacétal naturel possédant une très forte activité inhibitrice vis-à-vis de β-glycosidases. Son élaboration a été envisagée par couplage entre deux fragments clé : le 2-éthynyl-1,7-dioxaspiro [5.5] undécane et un iminocyclitol porteur d’un époxyde. La synthèse de ces deux composés a été réalisée en peu d’étapes et avec d’excellents rendements. Leur couplage a permis l’obtention d’un précurseur directe de la broussonétine H. L’étape finale de déprotection reste à optimiser afin de permettre l’isolement du produit naturelSpiroketal pattern appears in the skeleton of many natural products exhibiting various biological activities, and several synthetic routes to it have been reporting. Contrarily, spiroaminal moiety, its nitrogen analogue, has been less studied. The first of our objectives consisted to develop the most general enantioselective synthetic pathway to this framework. The adopted strategy is based on a key step acid-catalysed spirocyclisation of aminohydroxyketones, resulting from the sequential alkylation of acetone N,N-dimethylhydrazone by various iodide derivatives. If targeted spiroaminals could not be obtained, these polyfunctionalized ketones permit an efficient access to original spiroketals skeletons like 1,6-dioxaspiro [4.6] undecanes and 1,7-dioxaspiro [5.6] dodecanes. In a second part, we focused on the total synthesis of broussonetine H, a natural spiroketal possessing powerful inhibitory activities against β-glycosidases. Its elaboration was envisaged through the coupling between two key fragments : the 2-ethynyl-1,7-dioxaspiro [5.5] undecane and an iminocyclitol substitued by an epoxide. The synthesis of these two compounds was realized in few steps with good overall yelds.Their coupling led to a protected form of broussonetine H. The final deprotection step remains to be optimized to allow the final isolation of the natural product