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1
Cant, Alastair Alexander. "Investigations into aryne chemistry." Thesis, University of Edinburgh, 2012. http://hdl.handle.net/1842/6249.
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The first project in this thesis describes our research reacting arynes with tertiary allyl amines to generate functionalised anilines via a benzyne induced aza-Claisen reaction. This process works in good to excellent yields and the methodology can be further applied to make benzannulated medium sized ring amine systems. The second project covered in this thesis details our studies in the generation of benzyne from benzoic acid. This process utilises palladium catalysis involving an ortho C-H activation of benzoic acid which generates a 5 membered palladacycle. This palladacycle then spontaneously decomposes with heat to generate palladium bound benzyne and carbon dioxide. The yield of benzyne was monitored by observing the amount of triphenylene formed in the process. Further synthetic applications in this process were limited, but it was shown that the benzyne could be reacted with alkynes to generate phenanthrene and naphthalene products. The third project in this thesis details our work on the insertion of benzyne into the C–S bond of thioesters. Using palladium catalysis and an o-trimethylsilylphenyl triflate benzyne precursor, a variety of thioethers were produced. The yields for this reaction were moderate to good but it was found that only aromatic substituents were tolerated on the thioester.
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Liu, Zhijian. "Novel aryne chemistry in organic synthesis." [Ames, Iowa : Iowa State University], 2006.
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Pocock, Ian. "Novel cascade aryne-capture/rearrangement reactions." Thesis, University of Huddersfield, 2014. http://eprints.hud.ac.uk/id/eprint/23743/.
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Arynes are reactive intermediates that have been an academic curiosity for over a century. A recent renaissance of interest in the chemistry of these intermediates can be traced back to the development of ortho-(silyl)aryl triflates as aryne precursors. The application of aryne chemistry outside academia has been precluded by the expense and laborious preparation of these precursors. Diphenyliodonium-2-carboxylate has been shown to be a stable and inexpensive benzyne precursor, however application has been limited due to the high temperature (>160 ºC) and long reaction times required to generate benzyne by this protocol. Described within is an investigation whereby diphenyliodonium-2-carboxylate is successfully decomposed using microwave irradiation to generate benzyne. This proof of concept investigation shows diphenyliodonium-2-carboxylate can be applied as an off-the-shelf benzyne precursor; by using microwave radiation, significantly reduced reaction times and lower b.p. solvents can facilitate a more universal application of this protocol than previously described. The investigation into the reactions of allylamino malonates with arynes is also described. Simple allylamino malonates are shown to perform a novel cascade aryne capture/ring-closure/[2,3]-rearrangement to generate indolin-3-one products. The influence of substitution of the indolin-3-one products on the photophysical properties is probed. Tetrahydropyridine derived aminomalonates result in a ring contraction by [2,3]-rearrangement to N-phenyl pyrrolidine products. Further investigations show N-allyl proline methyl esters also generate indolin-3-one products by this novel cascade mechanism. The photophysical properties of these products are also probed. N-diallylalanine methyl ester is shown to generate indolin-3-one with benzyne however N-allyl sarcosine ethyl ester generates the N-phenyl -allylated amino esters product by aryne capture/[2,3]-rearrangement.
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Lin, Wenwei. "Preparation of Polyfunctionalized Grignard Reagents and their Application in Aryne Chemistry." Diss., [S.l.] : [s.n.], 2006. http://edoc.ub.uni-muenchen.de/archive/00006045.
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Schwan, Johannes [Verfasser]. "Step Efficient Synthesis of 3,4-Dioxygenated Quinolones Enabled by Aryne Chemistry / Johannes Schwan." Berlin : Freie Universität Berlin, 2020. http://d-nb.info/1219904783/34.
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Bates, Richard Simon. "Arene ruthenium chemistry." Thesis, University of Nottingham, 1990. http://eprints.nottingham.ac.uk/11890/.
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This thesis describes the synthesis and reactivity studies of new arene-ruthenium(II) and arene-ruthenium(O) complexes. Ultrasound has been investigated as an alternative energy source, with the overall aim of synthesising arene ruthenium clusters. Chapter 1 gives an introduction and summary of the known arene ruthenium chemistry reported to date. Chapter 2 reports the synthesis of (CGH6)Ru(C2H4)2 and (MeC6H4CHMe2)Ru(C2H4)2. Low temperature protonation studies generated (C6H6)Ru(H)(CZH4)2' and (MeC6H4CHMe2)Ru(H)(C2H4)7ý. These are observed by 1H nmr spectroscopy to undergo two dynamic processes, rotation of the ethylene ligands and an exchange between the hydride and the hydrogens of the ethylenes. On protonation with trifluoroacetic acid (C6H6)Ru(02CCF3)2 has been shown to be the final product. Nucleophilic substitution investigations of the bis(ethylene) complexes has determined that the arene is more labile than the coordinated ethylene. Chapter 3 reports the generation of a reactive intermediate, [(MeC6H4CHMez)Ru(THF)2]", and the reactions it undergoes. The synthesis and stereochemistry of the new complexes [(MeC6H4CHMe2)RuBr(C3H5)] and Ru(H)[(C6H40) (OPh)2][P(OPh)3]3 are reported. Chapter 4 describes the successful synthesis of the project goal, with the formation of the trimer [(MeC. H., CHMe2)3Ru3Se,_1` and the tetra nuclear species [(MeC6H4CHMe2)4Ru4H4]2'. Electrochemistry shows both complexes undergo two, one-electron reversible reductions to generate their neutral analogues. Ru3(CO)12 was formed when arene ruthenium carbonyl clusters were sought. Chapter 5 reports the formation and reactivity of arene ruthenium complexes containing nitrogen based ligands. The half sandwich complexes, (arene)RuCl2(NH2R) (arene = C6H6, R= Et, CMe, C6H4Me; McC6H4CHMe2, R=CMe3) and (C. H6)RuCl(NHZCGH4Me)Z' have been synthesised in good yield. However, these complexes are not synthetically useful as substrates for cluster synthesis, although (C6H6)RuC12(NH2CMe3) can be converted to the mixed ethoxide-halide dimer, [(C6H6)Ru(OEt)]2Cl`. Me3SiN3 on reaction with [(MeC6H4CHMe2)RuC12]2 affords [(MeC6H4CHMe2)RuCl(N3)]Z. An X-ray crystal structure determination of this complex showed the nitrogens bridging the two ruthenium atoms are pyramidal rather than the expected planar in geometry. [(MeC6H4CHMe2)RuCl(N3)]2 undergoes chloride loss to form the triply bridged dimer, [(MeCGH4CHMe2)RuCl(N3)z]', and bridge cleavage to form [(MeC, H4CHMe2)RuCl(N3)PPh3]. The latter complex is believed to undergo disproportionation in solution. Conclusions and future directions of the project are discussed in chapter. 6. The appendix provides a discussion of ultrasound proposed structure.
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Smith, Paul David. "Arene-ruthenium chemistry." Thesis, University of Nottingham, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.357040.
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Rooney, Aaron. "Asymmetric functionalisation in arene chromium tricarbonyl chemistry." Thesis, Imperial College London, 2007. http://hdl.handle.net/10044/1/11891.
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The research described in this thesis is concerned with the exploitation of a nonracemic chiral base to create enantiomerically enriched chiral centres on the benzylic positions of arene chromium tricarbonyl complexes. The first chapter is in two parts. The first part contains a historical overview of chiral bases and their use in asymmetric synthesis, as well as demonstrating the versatility of chiral base reactions. The latter part deals with the chemistry of arene chromium tricarbonyl complexes and how these molecules have been used in asymmetric synthesis and as ligands in asymmetric catalysis. The second chapter looks at the synthesis of a novel benzyl phosphine chromium tricarbonyl complex and attempts to asymmetrically deprotonate the molecule in order to create a new chiral monophosphine. The third chapter describes the generation of a range of novel monophosphine ligands, based on an arene chromium tricarbonyl core, by exploitation of an asymmetric deprotonationlelectrophilic quench sequence. the novel monophosphines have been assayed in the asymmetric hydrosilylation reaction, and the results are presented and discussed. The fourth chapter is a study of arene chromium tricarbonyl complexes of dibenzyl ethCl and a dibclIzy laminc, dnd their as) mmetr ie dept otonatiol'l. The genet [tHon of new C2-symmetric ethers with high enantioselectivity is demonstrated. The fifth chapter describes the attempted construction of a novel chiral C3-symmetric triol using the chiral base mediated asymmetric benzylic functionalisation approach. The sixth chapter contains the experimental details of the work presented in Chapters two, three, four and five. Chapter seven provides the bibliographic information.
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Lough, Julie Ann. "Aqueous solution chemistry of ruthenium arene anticancer complexes." Thesis, University of Warwick, 2010. http://wrap.warwick.ac.uk/35524/.
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Metal complexes currently are currently of much interest in the field of anticancer drug development. Platinum complexes such as cisplatin, are now widely used in the clinic and have led to a focus on the synthesis of new classes of other metal-based complexes, such as ruthenium anticancer drugs. In order to understand the mechanism of action of these complexes and to improve structureactivity relationships thereof, a comprehensive study of the solution chemistry is important. In this thesis the mechanism and kinetic detail of the exchange of amino protons on one such class of complex, [(η6-biphenyl)Ru(N,N’- ethylenediamine)Cl]+ was investigated in detail. Stereospecific assignment of NH protons was carried out by NOESY NMR on a pyridine adduct [(η6- biphenyl)Ru(N,N’-ethylendiamine)(N-pyridine)]2+. Using 1H and 2H NMR spectroscopy, rates of exchange were observed at different pH values, temperatures and ionic strengths a series of N-H/2H exchange reactions were studied and the data collected. The data are consistent with an exchange mechanism involving proton abstraction from the amine, followed by favourable reprotonation on the lowerface (relative to the overhanging arene) of the Ru(N,N’- ethylendiamine) five membered ring. In chlorido complexes this leads to the exchange of lower proton at a rate of three times that of those on the upperface at 298 K. To investigate the effects of electron density on the ruthenium on the exchange rates a series of π-donor pyridine ligands (pyridine, 4-methylpyridine, 4- tert-butylpyridine, and 4-methoxypyridine) in the place of the chloride were studied. The exchange rates were also investigated and showed a correlation between the basicity of the pyridine derivative and the favourability of exchange on the lower face, increasing this bias upto 11 fold. Density functional theory calculations suggests that there is an overlap between the p-orbital of the (ethylenediamine) nitrogen and the π*-antibonding orbital on the Ru-N(Pyridine) bond and σ*- antibonding orbital on the Ru-Cl bond, in their respective complexes. This overlap is proposed as a stabilising force on the deprotonated nitrogen allowing for a negative charge to be more stabile in one lobe of the p-orbital preferential to another. Following abstraction of the proton, the lone pair on the nitrogen is stabilised by an antibonding orbital, the top face less is susceptible to proton addition. Since DNA is a potential target for these complexes, the changes in shape induced by metal binding were investigated using Ion-Mobility Mass Spectrometry for the first time. Also in this work, the first ion-mobility mass spectrometry studies of the collisional cross sections (CCSs) of small complexes (<100 Å2) is also presented. This was developed using a new glycine based calibrant. Following binding of [(η6-biphenyl)Ru(N,N’- ethylenediamine)Cl]+ to the DNA hexamer d(CACGTG) changes in CCS values between ruthenated and non-ruthenated hexamers were studied. The change in CCS between these was not additive and suggestive of some folding or intercalation occurring upon ruthenium binding. Finally, attempts were madeto investigate shape change induced in DNA by binding to cisplatin using Förster Resonance Energy Transfer Methods are described. To date these results are inconclusive but work in this field is ongoing.
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Mehnert, Christian P. "Organometallic chemistry of molybdenum and iron and related studies." Thesis, University of Oxford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.318895.
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Al-Mandhary, Muna R. A. "Aspects of the chemistry of some osmium-containing clusters." Thesis, University of Cambridge, 1994. https://www.repository.cam.ac.uk/handle/1810/272646.
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Stinchcombe, J. "The chemistry of arene and cyclohexadienyl complexes of iron." Thesis, University of Nottingham, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335290.
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Matters, Justin Mark. "Some chemistry of ruthenium carbonyl clusters with arene ligands." Thesis, University of Cambridge, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.624659.
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Husain, Ali. "Synthesis of Functionalized Resorcin[4]arene via Click Chemistry." Scholar Commons, 2010. http://scholarcommons.usf.edu/etd/3460.
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Click chemistry is a very powerful chemical strategy that overcome carbon-carbon bond with carbon-heteroatom bond by joining small units with heteroatom links (C-X-C) using spring-loaded reactants. The Cu(I)-catalyzed Huisgen 1,3-dipolar cycloaddition is a major example based on the click chemistry philosophy. This method was used for the last 10 years to join different functional groups, carbohydrates, aminoacids, polymers to calix[4]arene and resorcin[4]arene cavitands by a stable 1,2,3-triazole linkages.
Herein I describe our interest in this type of click chemistry reaction in the synthesis of dimeric capsules resorcin[4]arene via four 1,2,3-triazole linkages. Two different resorcin[4]arene derivatives were synthesized in which four azide and four alkyne functional groups were attached on the upper rim of two different resorcin[4]arenes. The dimerization reaction was quite challenging due to steric factors. Each resorcin[4]arene derivative was then studied individually via click chemistry and all click reaction results were excellent and the products were isolated in good yields. These results enhanced the synthesis of the dimeric resorcin[4]arene.
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Jones, Neale G. "Chemistry of #pi#-arene and #pi#-allyl complexes of molybdenum." Thesis, University of Oxford, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.365776.
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Lee, Kieseung. "Synthetic studies towards Ristocetin A and related compounds using arene-ruthenium chemistry." Case Western Reserve University School of Graduate Studies / OhioLINK, 1995. http://rave.ohiolink.edu/etdc/view?acc_num=case1062528216.
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Al, Jammaz Ibrahim J. "Solution chemistry of calix[4]arene amide derivatives : applications in radiopharmaceuticals." Thesis, University of Surrey, 1998. http://epubs.surrey.ac.uk/842865/.
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Following an overview in the field of calixarene chemistry given in the introduction, this thesis reports, i) The synthesis of p-text-butylcalix[4]arene tetraacetamides, thiophosphates and derivatives containing mixed functional groups and the characterisation by IR, NMR and microanalysis. ii) The solution thermodynamic of p-tert-butylcalix[4]arene tetradiisopropylacetamide and the transfer thermodynamics of this ligand from acetonitrile to various solvents. iii) Spectrophotometric, potentiometric and calorimetric studies on the interaction of p-tert-butylcalix[4]arene tetraacetamides and metal cations in butan-l-ol and in water saturated butan-l-ol at 298.15 K. Metal-ion complexes of p-tert-butylcalix[4]arene tetradiisopropylacetamide were isolated and characterised by IR, NMR and spectroscopy and microanalysis. In butan-l-ol, the selectivity of this ligand for metal cations follows the sequence Na+ > Cd2+ > Pb2+ > Zn2+ > Ag+. However, this sequence is altered in the water saturated solvent to an extent that the strong complexation observed for this ligand and zinc(II) in butan-l-ol is non-existent in the water saturated solvent. Using complexation data in conjunction with solution data of the host, the guest and the resulting complex, enthalpies of coordination (referred to the process which reactants and the product in the solid state) were calculated. iv) Extraction experiments in the water-butan-l-ol solvent system at 298.15 K in the presence of p-tert-butylcalix[4]arene tetradiisopropylacetamide were performed. The higher extraction of lead(II) relative to other metal cations from the aqueous solution to the organic phase in the presence of the ligand at low hydrogen-ion concentration is demonstrated. The extraction of radioactive lead(II) by the same ligand was investigated as a function of i) the pH of the aqueous phase ii) the ligand concentration in the organic phase. vi) A new polymeric material was obtained by attaching the ligand to the polymer. Final conclusions are drawn and suggestions for further work in this area are given.
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Puntambekar, Shakher Gajanan. "Half-sandwich arene iron complexes : synthesis and reactivity." Thesis, University of Nottingham, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.329900.
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Blagg, J. "Arene chromium tricarbonyl complexes in synthesis." Thesis, University of Oxford, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376895.
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Pitt, Melanie A. 1980. "Main group supramolecular coordination chemistry: Design strategies and dynamic assemblies." Thesis, University of Oregon, 2009. http://hdl.handle.net/1794/10287.
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xxi, 172 p. : ill. (some col.) A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number.Main group supramolecular chemistry is a rapidly expanding field that combines the tools of coordination chemistry with the unusual and frequently unexpected coordination preferences exhibited by the main group elements. Application of established supramolecular design principles to those elements provides access to novel structure types and the possibility of new functionality introduced by the rich chemistry of the main group. Chapter I is a general review of the field of main group supramolecular chemistry, focusing in particular on the aspects of coordination chemistry and rational design strategies that have been thus far used to prepare polynuclear "metal"-ligand assemblies. Chapter II is a discussion of work toward supramolecular assemblies based on the coordination preferences of lead(II), in particular focusing on the 2-mercaptoacetamide and arylthiolate functionalities to target four-coordinate and three-coordinate geometries, respectively. Several possible avenues for further pursuing this research are suggested, with designs for ligands that may provide a more fruitful approach to the coordination of lead(II). Chapter III deals with the preparation of As 2 L 3 assemblies based on flexible ligand scaffolds. These assemblies exhibit structural changes in response to temperature and solvent, which may provide some insight into the subtle shape requirements involved in supramolecular guest binding. Chapter IV continues this work with an examination of how ligand structure affects mechanical coupling of stereochemistry between metal centers when the chelate ring is completed by a secondary bonding interaction such as the As-π contact. Finally, Chapter V presents a crystallographic and synthetic study of the nature of the interaction between pnictogens and arene rings. This interaction is ubiquitous in the coordination chemistry performed in the Johnson laboratory; understanding the role these interactions play in determining the final structure of supramolecular assemblies is vital to the preparation of more complex structures. Chapter VI presents a set of conclusions and outlook for future work on lead(II) supramolecular assemblies and the dynamic assemblies prepared from flexible organic scaffolds. This dissertation contains previously published and coauthored material.
Committee in charge: Kenneth Doxsee, Chairperson, Chemistry; Darren Johnson, Advisor, Chemistry; David Tyler, Member, Chemistry; Victoria DeRose, Member, Chemistry; Stephen Remington, Outside Member, Physics
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Rijt, Sabine H. van. "Osmium arene anticancer complexes." Thesis, University of Warwick, 2010. http://wrap.warwick.ac.uk/3213/.
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Drawbacks associated with anticancer chemotherapeutic cisplatin include tumour drug resistance, non-effectiveness against all tumours and lack of tumour-specificity resulting in severe side-effects (e.g. nausea, hair loss and kidney toxicity). The use of other metals such as transition metals rutheniumandosmium, may address the problems associated with platinum drugs and have received increased interest over the years. In this thesis the biological activity and aqueous solution chemistry of half-sandwichosmium (II) compounds of the type [(arene)OsII(X)(YZ)] n+ is explored. Chelating ligands containing nitrogen or nitrogen and oxygen donor atoms (N, NandN, O-chelatingligands) are investigated. It is shown that the chelating ligand has a large effect on the aqueous reactivity of the complexes. The introduction of functional groups on the chelate allowed for the ‘fine-tuning’ of the aqueous reactivity and nucleobase binding of the complexes. Also the nature of the coordinating arene was found to have an important effect on their biological activity. This could be rationalised by increased hydrophobicity with more extended arenes such as biphenylandtetrahydroanthracene, resulting in increased cellular uptake and increased cytotoxicity. Conjugating cell penetrating peptides to the complexes resulted in improved biological properties and opened a new way for functionalisation of the compounds. Several compounds reported in this thesis exhibit promising activity in the ovarian, colon and lung cancer cell lines and some could overcome cisplatin resistance in ovarian cisplatin resistant cell lines. Initial studies revealed cell death via apoptosis and the possible involvement of mitochondria in the apoptotic pathway. These results point to a novel pathway of activation for these complexes which is advantageous for addressing chemoresistance and effectiveness to oher types of cancers. This work shows that the biological properties of these compounds can be tuned by choice of ligands and also provides initial evidence for a novel pathway of activation.
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Gleave, Catherine Ann. "Synthetic receptors based upon calix[4]arene." Thesis, University of Liverpool, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240754.
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Leaym, Xiaoxuan. "Synthesis and applications of novel resorcin[4]arene cavitands." Diss., Manhattan, Kan. : Kansas State University, 2008. http://hdl.handle.net/2097/745.
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Ben, Aziza Haifa. "The pillar [5] arene as a polyfunctional core for the development of molecular materials." Thesis, Strasbourg, 2015. http://www.theses.fr/2015STRAF067/document.
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La préparation de briques élémentaires de pillar[5]arènes « clickables » nous ont permis de construire des édifices moléculaires complexes, en greffant différents groupements fonctionnels autour du coeur macrocyclique. Dans ce contexte, des nouveaux dérivés du pillar[5]arène présentant des propriétés cristaux-liquides ont été synthétisés en greffant du p-dodecyloxybenzoate ou encore des dendrons de type percec. D’autres part, des dérivés pillarèniques portant des unités de porphyrines ont été préparés à partir du squelette « clickable » pillar[5]arène et de porphyrines de Zinc portant des fonctions alcynes vrai. Les études de ce système par RMN du proton à des températures variables ont permis de mettre en évidence un équilibre conformationnel dynamique conduisant au repliement des molécules. Ceci a été expliqué par une complexation intramoléculaire des porphyrines de Zinc par les groupements 1,2,3-triazole. Finalement un support « clickable » detype [2]rotaxane comportant une porphyrine base libre comme bouchon, a été préparé et ensuite fonctionnalisé par dix porphyrines de Zinc permettant l’obtention d’un dispositif supramoléculaire photoactifClickable pillar[5]arene building blocks have been used for the efficient grafting of peripheral subunits onto the macrocyclic core. New liquid-crystalline pillar[5]arene derivatives have been prepared by grafting either p-dodecyloxybenzoate groups or percec-type dendrons on the macrocyclic scaffold. On the other hand, pillar[5]arene derivatives bearing peripheral porphyrin subunits have been efficiently prepared from the clickable pillar[5]arene building block and Zn(II)-porphyrin derivatives bearing a terminal alkyne function. Owing to an intramolecular complexation of the peripheral Zn(II)-porphyrin moieties by 1,2,3-triazole subunits, an original dynamic conformational equilibrium leading to a folding of the molecules has been evidenced by variable temperature 1H NMR studies. Finally, a clickable [2]rotaxane scaffold incorporating a free-base porphyrin stopper has been prepared and functionalized with ten peripheral Zn(II)-porphyrin moieties to afford a sophisticated photoactive supramolecular device
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Ismail, Ashraf A. "Chalcocarbonyl chemistry : application in hormonal receptor determination, metalloporphyrins and metal-arene bond activation." Thesis, McGill University, 1985. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=72063.
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The reaction of ((eta)-Arene)Cr(CO)(,2)(CX) (X = S, Se) complexes with excess (RO)(,3)P (R = Me, Et, n-Bu, Ph) yields Cr(CO)(,2)(CX) (RO)(,3)P (,3), predominantly as the mer I isomer, in which a phosphite ligand is trans to CX. Arene displacement from ((eta)-C(,6)H(,6))Cr(CO)(,2)(CX) by tridentate phosphine ligands L-L-L L-L-L = (Me)C(CH(,2)P(Ph)(,2))(,3), (Ph(,2)PCH(,2)CH(,2))(,2)PhP gives fac-(L-L-L)Cr(CO)(,2)(CX) products. The molecular structures of Cr(CO)(,2)(CX) (MeO)(,3)P (,3) have been determined by single crystal X-ray diffraction. Intramolecular isomerization of these complexes as well as their tricarbonyl analogue has been demonstrated and activation parameters have been calculated for the rearrangement processes. Two-dimensional ('31)P NMR spectroscopy has provided evidence that isomerization occurs via trigonal prismatic intermediates. Kinetic investigations of the reaction of ((eta)-C(,6)H(,6))Cr(CO)(,2)(CX) with (MeO)(,3)P have established a first-order rate dependence on both the complex and the entering ligand. The faster reaction rate of the selenocarbonyl derivative relative to its thiocarbonyl analogue originates in a lower entropy of activation in the former case. The effect on the reaction rate of variation in the nature of the arene and of the entering ligand has been investigated.An approach to hormonal receptor assay involving the detection by FT-IR spectroscopy of Cr(CO)(,3)-labelled modified estradiol bound to estrogen receptors in target tissue is reported.
The FT-IR spectra of FeTPP(CX) FeTPP = (5,10,15,20-tetraphenyl-porphinato)Fe(II); X = S, Se and FeTPP(CX)L (X = S, Se; L = pyridine, ethanol) have been obtained. Some changes in the porphyrin spectrum were observed with variation or removal of L, but not with variation of X.
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Patchett, Ruth. "Coordination chemistry of N-heterocyclic carbene and thione functionalised calix[4]arene ligands." Thesis, University of Warwick, 2016. http://wrap.warwick.ac.uk/89822/.
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This thesis is a summary of the work carried out exploring the properties and applications of calix[4]arene ligands. Particular attention is given to the flexibility and encapsulation capabilities of these species. Initially synthetic methodology for the incorporation of bisimidazolinium and imidaolium groups was targeted. The synthesis of imidazolinium functionalised species proved problematic, however pro-ligand 2a-2HI was readily prepared via a six-step synthetic procedure. The coordination chemistry of 2a-2HI with [Rh(COD)Cl]2 and [Rh(CO)2Cl]2, via generation of the free carbene (2a) or transmetallation from an isolated silver complex (6a) was explored. Both routes resulted in the formation of bimetallic species. The isolation of these complexes highlights the flexibility of the calix[4]arene scaffold. The role of the calix[4]arene was probed though comparison to complexes of the monodentate IiPr2Me2 ligand. Based on these results, the imidazole-2-thione (NHCS) ligand 3 was derived from 2a and elemental sulfur. Monodentate rhodium and iridium complexes of 3 were readily prepared and found to bind potassium cations within the calix[4]arene cavity. This unusual host-guest chemistry was probed by 1H NMR spectroscopy and in the solid state through comparison to other calix[4]arene hosts.
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Neesu, Rachana. "Fused Arene-Based Molecular Systems as Additives for Organic Photovoltaics." TopSCHOLAR®, 2015. http://digitalcommons.wku.edu/theses/1471.
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Organic photovoltaics (OPVs) are mainly based on organic semiconducting small molecules, macromolecules, and polymers, which form an active layer in photovoltaics. They act as an active material in absorbing light and causing charge mobility to generate electricity from sunlight. This thesis describes the molecular systems derived from fused arenes such as anthracene, pyrene, carbazole and thiophene for use as either a donor or an acceptor component of the active layer of OPVs. Two novel molecular systems (9- anthracenecarboxy-1-methylpyrene, (1) and Py-bi-TH-ANT, (2) were prepared using Steglich esterification and Grignard metathesis followed by Kumada coupling. The molecular structure of each was confirmed by 1H-NMR and IR analysis respectively. The photophysical properties of the products were also evaluated in solution. The potential applicability of these two novel systems for OPVs will be studied in the future.
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Diaconescu, Paula L. (Paula Loredana) 1976. "Arene bridged diuranium compounds supported by amide and ketimide ligands." Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/29638.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemistry, 2003.Vita.
Includes bibliographical references.
Chapter 1: The Intriguing Geometric and Electronic Structure of Arene-Bridged Diuranium Tetrakisamido Complexes The focus of this chapter is to characterize and contextualize the bridged arene complex (-toluene)U2(N[t-Bu]Ar)4 (lb2-gl-toluene, Ar = 3,5-C6H3Me2). To do so, lb2-g-toluene is compared extensively with the mononuclear complexes (THF)U(N[1Ad]Ar)3 (2a-THF, THF = tetrahydrofuran), JIU(N[t-Bu]Ar)3 (la-I), IU(N['Ad]Ar)3 (2a-I), and Me3SiNU(N[1Ad]Ar)3 (2a- NSiMe3). In order to understand the properties of a unique compound such as lb2-pg-toluene, the rest of the series is based on classical uranium amide compounds. The syntheses, structures (X-ray crystal structures and solution behavior based on variable temperature, VT, NMR data), spectroscopic (X-ray absorption near-edge structure, XANES, and electronic absorption - UV- vis-NIR) and magnetic properties are discussed and interpreted with reference to results of density functional theory (DFT) calculations performed on model compounds. Reactivity studies of lb2-p-toluene are then presented and analyzed. Chapter 2: Arene Bridged Diuranium Complexes Supported by a Ketimide Ligand: Even and Odd Electron Redox Pairs The ketimide ligand NC[t-Bu]Mes (Mes = 2,4,6-C6H2Me3) employed in the present study allows for retention of three supporting ligands per uranium, giving rise to a three-legged piano stool geometry, and it also allows for incorporation of potassium ions as tight ion pairs. The generality of such a ligand is well supported by the existence of the two types of compounds M2(g-arene)U2(NC[t-Bu]Mes)6 (M2-32-g-arene, M = Na, K) and K-32-pt-arene, when the arene is naphthalene, biphenyl, trans-stilbene, or p-terphenyl.
(cont.) When toluene or benzene is the bridging arene, only odd electron species are formed including symmetrical complexes, K21-32- -arene', and asymmetrical complexes, K(DME)-32-g1-arene' (arene' = benzene, toluene). The reactivity patterns observed for the bridging arene ketimide compounds are complicated by loss of an alkali metal ion (K2-32-jg-arene with PhSSPh) or by additional redox processes (K-32-gl-arene with PhNNPh), but interesting products have been isolated. By contrast, the reaction of K2-32-g-arene with 1,3,5,7-cyclooctatetraene appears to be straightforward leading to K-3-COT. Compound 32-I-COT obtained from reaction of K-3-COT with 3-I-DME is an interesting example of an inverted sandwich and can be referred to as "inverted uranocene". Chapter 3: Uranium 2,2'-Bipyridyl Complexes Supported by Amide and Ketimide Ligands The synthesis and characterization of (bipy)2U(N[t-Bu]Ar)2 (lb-(bipy)2, bipy = 2,2'-bipyridyl, Ar = 3,5-C6H3Me2), (bipy)U(N[1Ad]Ar)3 (2a-bipy), (bipy)2U(NC[t-Bu]Mes)3 (3-(bipy)2, Mes = 2,4,6-C6H2Me3), and IU(bipy)(NC[t-Bu]Mes)3 (3-I-bipy) are reported. X-ray crystallography indicates that bipy coordinates as a radical anion in lb-(bipy)2 and 2a-bipy, and as a neutral ligand in 3-I-bipy. In 3-(bipy)2, one of the ligands is best viewed as a radical anion, while the other as a neutral ligand. These results are supported by NMR spectroscopy results of exchange experiments with 4,4'-dimethyl-2,2'-bipyridyl (dmb) and optical spectroscopy. In all complexes uranium is assigned a +4 formal oxidation state.
by Paula L. Diaconsescu.
Ph.D.
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Herbert, Simon Anthony. "Oxazoline directed lithiation of Calix[4]arene and Ferrocene." Thesis, Stellenbosch : Stellenbosch University, 2011. http://hdl.handle.net/10019.1/17867.
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Thesis (PhD)--Stellenbosch University, 2011.ENGLISH ABSTRACT: The use of chiral oxazoline directed lithiation provides a highly diastereoselective (up to >99% de) route to meta functionalised inherently chiral calixarenes. This methodology can be used on both the butylated and debutylated calixarene systems and is tolerant of a wide range of different electrophillic quenches allowing access to a structurally diverse range of inherently chiral metafunctionalised calixarenes. The oxazoline directing group can be removed via hydrolysis, generating a range of functionalised calixarene carboxylic acids in high ee. We also demonstrate that the use of derivative alkyllithiums such as cyclopentyl lithium can provide significantly enhanced diastereoselectivity over the conventional organolithiums such as sec-butyl lithium, when employed in ortholithiation reactions of this nature. The differences in diastereoselectivity associated with the different alkyllithiums can be tied, in certain cases, to the steric bulkiness associated with the individual reagents. In this regard we have found that the use of the so called Tolman angle or cone angle approach allows quantification of the relative steric bulk of the alkyllithium. We also detail that the oxazoline directing group provides a hitherto unknown ability to be diastereoselectively tuned through the choice of the ligand system in the ortholithiation reaction. In this regard the development of a series of diglyme based ligands have proved to provide a highly diastereoselective means of inverting the chirality from that which the use of the conventional TMEDA ligand is able to generate (up to –92% de). The use of diglyme ligands to invert the sense of chirality is also shown to occur on the ferrocenyloxazoline system and presents an apparently general and hitherto unknown facet of asymmetric oxazoline directed ortholithiation. This diglyme induced inversion has been shown to be controlled through a secondary nitrogen coordinated mechanism that is able to operate with chiral oxazolines.
AFRIKAANSE OPSOMMING: Die gebruik van chirale oksasoliengerigte litiëring verskaf ’n hoogs diastereoselektiewe (tot en met >99% do) roete om metagefunksionaliseerde, inherente chirale calixareen produkte te sintetiseer. Deur gebruik te maak van verskillende elektrofiele kan die metodologie toegepas word op beide gebutileerde en de-gebutileerde calixareen sisteme om ’n reeks uiteenlopende inherente chirale, meta-gefunksionaliseerde calixareen produkte te vorm. Die oksasolien groep kan daarna verwyder word deur hidroliese om ’n reeks gefunksionaliseerde calixareenkarboksielsure te vorm in baie hoë eo. Ons het ook gedemonstreer dat die gebruik van afgeleide alkiel-litiums, soos siklopentiel-litium, kan bydrae tot aansienlik verhoogde diastereoselektiwiteit as dit vergelyk word met meer algemene organolitiums soos sekbutiellitium, tydens ortolitiëring reaksies van hierdie natuur. Die verskille in diastereoselektiwiteit kan verbind word, in sekere gevalle, tot die steriese bonkigheid van die individuele reagense. Deur gebruik te maak van die sogenaamde Tolmanhoeke of die koniesehoek benadering is dit moontlik om die relatiewe steriese bonkighied van alkiellitiums te kwantifiseer. Daar was ook bepaal dat die oksasoliengroep die ongekende vermoë besit om die diastereoselektiwiteit van die produk te stem deur die keuse van verskillende ligand sisteme tydens die ortolitiëring reaksie. Daar was bepaal dat die chiralitiet van die produkte omgekeer kan word op ’n hoogs diastereoselektiewe manier, deur gebruik te maak van ’n reeks ontwikkelde diglymegebaseerde ligande, indien dit vergelyk word met die produkte wat deur die konvensionele TMEDA gegenereer was (tot en met –92% do). Die gebruik van diglyme ligande was ook getoets op ferroseenoksasolien sisteme en dit was bevind dat dieselfde omkering in chiraliteit ook plaasvind wat aanleiding kan gee tot 'n oënskynlik algemene en tot nou toe onbekende faset van asimmetriese oksasoliengerigte orto-litiëring. Dit is bepaal dat hierdie diglyme geïnduseerde omkering in chiraliteit beheer word deur middel van 'n sekondêre stikstofgekoördineerde meganisme, wat in staat is om saam te werk met chirale oksasoliene.
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Betanzos, Lara Soledad. "Design, synthesis and activation of ruthenium arene anticancer complexes." Thesis, University of Warwick, 2010. http://wrap.warwick.ac.uk/4509/.
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The synthesis and characterisation of RuII complexes of the form [(η6-arene)Ru(N,N')X]+ (where N,N' is a bidentate chelating ligand and X is a halogen) are described; including the X-ray crystal structures of four of these complexes. The hydrolysis rates at 310 K of the complexes vary over many orders of magnitude and in some cases are followed by partial arene loss. Density Functional Theory (DFT) calculations suggest that the aquation mechanism occurs via a more associative pathway. The significant cytotoxic activity towards A2780 human ovarian cancer cells of some of the complexes is found to be dependent on the chelating ligand. Selective binding to 9-ethylguanine (9-EtG) but not to 9- ethyladenine (9-EtA) is observed in aqueous solution at 310 K in all cases. The X-ray crystal structure of a RuII arene 9-EtG adduct is also described. DFT calculations show that the 9- EtG nucleobase adducts of all complexes are thermodynamically preferred compared to those of 9-EtA. Preliminary CT-DNA studies in cell-free media suggest that some of these complexes can interact with DNA. A family of piano-stool RuII arene complexes of the form [(η6-arene)Ru(N,N')(L)]2+ (where N,N' is a chelating ligand and L is a pyridine or a pyridine-derivative), that can selectively photodissociate the monodentate ligand (L) when excited with UVA or visible light is described. The X-ray crystal structures of five of these complexes are also discussed. Their photoactivation allows the formation of a reactive aqua species that otherwise would not form in the dark. Results from TD-DFT calculations suggest that all the RuII pyridine complexes follow a relatively similar L-ligand photodissociation mechanism, likely to occur from a series of 3MC triplet states. It is shown how light activation can be used to phototrigger binding of these complexes to nucleobases with specific preference towards 9- EtG over 9-EtA. CT-DNA studies suggest that photoirradiated complexes interact with DNA via a combined coordinative, intercalative, and monofunctional binding mode. Some of the complexes are also cytotoxic against A2780 human ovarian cancer cell line in the absence of irradiation. The possibility of photo(triggering) hydride-transfer reactions using RuII arene complexes, NAD+, and formate as the hydride source under biologically relevant conditions is shown. The reactions occur either upon the spontaneous hydrolysis of a Ru–Cl bond in complexes of the form [(η6-arene)Ru(N,N')Cl]+ (where N,N' is a bidentate chelating ligand) or upon the photolysis of a Ru–N(Py) bond in [(η6-arene)Ru(N,N')Py]2+ (Py is pyridine). A mechanism involving the formation of a stable formate adduct followed by a hydrogen β- elimination is proposed. It is also demonstrated how a hydride-transfer from 1,4-NADH to some RuII arene chlorido complexes can occur in aqueous solution. Neutral RuII arene complexes of the form [(η6-arene)Ru(NH3)Cl2] which are constitutional analogues of cisplatin were synthesised by a novel synthetic method. These analogues display extensive H-bond interactions in the solid state as shown by X-ray crystal structures determination and their biexponential hydrolysis rates at 310 K vary over many orders of magnitude. The complexes are found to readily form mono- and di-guanine adducts upon hydrolysis but are not cytotoxic against the A2780 human ovarian cancer cell line up to the maximum concentration tested (100 μM).
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Cosstick, Kevin. "Regio- and stereochemical aspects of arene-ethene cycloaddition reactions." Thesis, University of Reading, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.258238.
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Nic, Miloslav. "Some studies of through space functional group-arene interactions." Thesis, University College London (University of London), 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307754.
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Perry, Mark A. "Spectroscopic investigations of perfluoroarene: Arene interactions in solution involving hexafluorobenzene." Thesis, University of Ottawa (Canada), 2008. http://hdl.handle.net/10393/28014.
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This thesis focuses on common spectroscopic techniques to measure the photophysical consequences of perfluoroarene:arene interactions in solution. The perfluoroarene in these studies was hexafluorobenzene (C6F 6) since it structurally and electronically represents the simplest of all perfluorinated aromatic molecules. The goal of this thesis was to create a library of perfluoroarene:arene interactions and use them to influence chemical reactivity in the excited state both efficiently and predictably. The first chapter outlines the spectroscopic techniques employed, and explains the foundation of this project from solid-state applications.
The remaining chapters detail perfluoroarene:arene interactions observed, spectroscopically, in solution. Chapter 2 is a thorough study on the pre-association of pyrene:C6F6 and the impact C6F6 had on the photophysics of dilute and concentrated pyrene solutions. The third chapter summarizes the photophysical results from a variety of rigid polyaromatic molecules, and one flexible polyaromatic (biphenyl). A practical application of this work was observed with nanosecond laser flash photolysis studies outlined in Chapter 4, while the search for other practical applications with quantum dots, oxygen- and carbon-centered radicals in the presence of C6F 6 is detailed in Chapter 5.
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Meichsner, Eric. "Modifications chimiques contrôlées du pillar[5]arène et préparation de [2]rotaxanes." Thesis, Strasbourg, 2017. http://www.theses.fr/2017STRAF046.
Full textAbstract:
Analogues aux cyclotrivératrilènes et aux calix[n]arènes, les pillar[n]arènes sont composés de n unités hydroquinoliques et reliés entre elles par un pont méthylénique en position para. Ces macrocycles ont été utilisés en tant que supports fonctionnalisables afin de préparer divers nanomatériaux. Dans ce contexte, la modification chimique du pont méthylénique a été réalisée sur le pillar[5]arène afin d’obtenir un nouveau site de fonctionnalisation, à ce jour jamais exploité. L’oxydation de cette position a permis dans un premier temps de réaliser une extension de cycle par une réaction de Colvin, afin d’obtenir un macrocycle portant une triple liaison tendue. Cette particularité a permis la réalisation de cycloaddition 1,3-dipolaire de Huisgen ou chimie click sans utilisation de cuivre(I), mais également l’obtention de produits de cycloadditions [2+2] par voie thermique normalement interdites. L’introduction d’un fullerène C60 sur ce pont méthylénique a également été réalisée sans déformation de la cavité. C’est pourquoi dans un deuxième temps des [2]rotaxanes photoactifs ont pu être élaborés à partir de ce fulléropillar[5]arène. Dans un dernier temps, une nouvelle méthode de préparation des [2]rotaxanes a été développée. Par échange de bouchons activés, divers [2]rotaxanes ont pu être synthétisés, sans être limités par la nature des bouchons souhaités. A partir de cette méthode de préparation, des cristaux liquides ont pu être obtenus en substituant ces bouchons activés par des bouchons portants des groupements post-fonctionnalisables, puis en greffant des groupements cyanobiphénylesAnalogues of cyclotriveratrylenes and calix[n]arenes, pillar[n]arenes are composed of 1,4-disubstituted hydroquinone subunits linked by methylene bridges in their para positions. This macrocyclic core has been used as a compact scaffold for the preparation of nanomaterials. In this context, the chemical modification of the methylene bridge has been achieved to further functionalize the core in a way never explored so far. Firstly, oxidation of this position followed by Colvin reaction generated a strained triple bond in the macrocyclic scaffold. This particularity allowed the introduction of functional groups under copper free Huisgen 1,3-dipolar cycloadditions as well as by thermal [2+2] cycloadditions normally prohibited. Insertion of [60]fullerene on the methylene bridge has been also carried out. In a second time, photoactive [2]rotaxanes have been obtained from this fulleropillar[5]arene. Finally, a new methodology for the preparation of [2]rotaxanes has been developed. By exchange of activated stoppers, various [2]rotaxanes were thus obtained and this method is not limited by the nature of the stopper. This methodology has been used to prepare new liquid crystalline rotaxane derivatives by introduction of clickable stoppers followed by the grafting of dendritic mesogenic subunits
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Jin, Ping Atwood J. L. "Synthesis of mixed metal-organic pyrogallol[4]arene nanocapsules and their host-guest chemistry." Diss., Columbia, Mo. : University of Missouri--Columbia, 2009. http://hdl.handle.net/10355/6874.
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Title from PDF of title page (University of Missouri--Columbia, viewed on Feb 24, 2010). The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Dissertation advisor: Dr. Jerry L. Atwood. Vita. Includes bibliographical references.
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Reid, Suazette N. "Synthetic stratergies [sic] towards a diureidocalix[4]arene." Thesis, Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/4961.
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Self-organization is a common occurrence among molecules in nature and questions of how and why these molecules interact and come together by intermolecular forces has been under investigation by those interested in molecular recognition. Synthetic molecules able to mimic nature have become important in the area of supramolecular chemistry. Calixarenes are a group of molecules that is being investigated for their ability to self-assemble into dimeric capsules. Such capsules can be very useful for catalysis, molecular recognition and for encapsulation. The synthetic stratergies involved in the synthesis of a diureidocalix[4]arene is presented. In this case the taget molecule is a tetrapropylcalix[4]arene substituted on the upper rim with two urea groups separated by a hydrocarbon chain will be synthesized. This molecule can then be used to investigate its dimerization properties.
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Fu, Ying. "Organometallic osmium arene anticancer complexes." Thesis, University of Warwick, 2011. http://wrap.warwick.ac.uk/52695/.
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The interest in the development of anticancer metal complexes for cancer therapy is growing spurred by the encouraging successful stories of platinum drugs. Osmium arene chlorido complexes had been found to show anticancer activity in vitro. In this thesis, the osmium arene iodido complexes were mainly explored and investigated. It is found that iodido OsII arene complexes with a general structure: [Os(η6- arene)(XY)I]PF6 (XY = p-hydroxy or p-dimethylamino phenylazopyridine, arene = p-cymene or biphenyl) are potently cytotoxic at nanomolar concentrations toward a panel of human cancer cell lines. In contrast to the chlorido osmium arene anticancer complexes, the iodido complexes are stable and inert toward aquation. More than thirty half sandwich azopyridine OsII arene complexes [Os(η6- arene)(azopyridine)X]+ (where X is chloride or iodide, the arene is p-cymene or biphenyl and the pyridine ring of azopyridine ligand bearing a variety of substituents) were synthesized and characterized. A preliminary structure activity relationships (SARs) were built up based on the anticancer activity towards A2780 human ovarian cancer cell line. In general, the introduction of an electronwithdrawing group (e.g. F, Cl, Br or I) at specific positions on the pyridine ring significantly increases cytotoxic activity and aqueous solubility. Changing the arene from p-cymene to biphenyl or the monodentate ligand (X) from chloride to iodide resulted in a significant increase in the anticancer activity. Studies in A2780 human ovarian cancer cells suggested that cellular uptake and targeting to cellular organelles play important roles in determining the anticancer activity. According to the 60 cancer cell lines screening results from National Cancer Institute (NCI), the anticancer activity achieved by the most potent OsII arene azopyridine complex is 100 times more than cisplatin; 1000 times activity was found in some cell lines. The mechanism of action may involve the inhibition of tubulin polymerization. One iodido osmium complex was selected for anticancer efficiency evaluation in vivo: [Os(η6-p-cym)(Azpy-NMe2)I]PF6 (FY026). This complex delayed the growth of HCT116 human colon cancer xenografts in mice, with negligible toxicity. It is the first example of in vivo antitumour activity for an organometallic osmium arene complex. Its activity appears to involve redox mechanisms. Its potency towards A2780 ovarian and A549 lung cancer cells is increased significantly when used in combination with L-buthionine-sulfoximine (L-BSO) indicating that L-BSO can be a good candidate for combination therapy treatment with iodido osmium complexes. Further study on the bioisosteres of FY026 was carried out by changing the azo bond (N=N) to imine bond (CH=N). Sixteen osmium arene iminopyridine complexes were synthesized, well characterized and showed good anticancer activity. Different structure-activity relationships comparing iminopyridine complexes with azopyridine complexes were identified which suggested a different anticancer mechanism. In contrast to FY026, [Os(η6-p-cym)(Impy- NMe2)I]PF6 (6) and [Os(η6-p-cym)(Impy-NMe2)Cl]PF6 (14) were found to undergo hydrolysis and the binding was observed between their hydrolyzed product (14A) and 9-ethylguanine. Moreover, a hydride transfer from NADH to form an osmium hydride intermediate which is involved in a catalytic process resulting in the formation of NAD+ was discovered. This process might be involved in the anticancer mechanism of action. A dual mechanism of action was proposed based in the interaction of these compounds with DNA nucleobase and catalytic oxidation of NADH.
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Gray, Jennifer C. "Ruthenium and osmium bis-arene complexes with biologically-active ligands." Thesis, University of Edinburgh, 2008. http://hdl.handle.net/1842/2758.
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The inclusion of biologically-active ligands into organometallic complexes offers much scope for the design of novel drugs with enhanced, targeted activity. Studies on such complexes indicate that new mechanisms of action are possible when combining the bioactivity of the ligand with the properties inherent to the metal, leading to the possibility of overcoming current drug resistance pathways. This thesis is concerned with the synthesis and characterisation of ruthenium(II) and osmium(II) bis-arene complexes containing biologically-active ligands and their potential application as anticancer agents. Four groups of ligands are investigated: indole derivatives, aspartame, tamoxifen and flavonoids. Both indole derivatives studied resulted in the formation of complexes which were unstable, due to either polymerisation of the ligand or decomposition of the complex as a result of loss of the bound ligand with time. X-ray structural data obtained for [(eta6-p-cymene)Ru(eta6-1-methylindole-3-acetic acid)](PF6)2 revealed that the latter may be a result of partial loss of eta6-coordination due to tilting of the indole ring away from the metal. Much more stable complexes were generated with aspartame, however the effect of the metal on the structure, electronics, acidity and decomposition of the ligand all resulted in the complexes being incapable of binding to and activating the human sweet taste receptor. Antiproliferative studies found that ruthenium and osmium complexes of tamoxifen were not active against hormone-dependent mcf-7 breast cancer cells although they were able to mimic the isolated ligand under certain conditions. Here, the inactivity is most likely a result of the organometallic fragment being too bulky to fit into the receptor active site. Although no cytotoxic activity was observed, evidence of intercalation of the complexes into DNA was obtained. Dual anticancer activity was discovered for two ruthenium complexes of flavonoids: [(eta6-p-cymene)Ru(eta6-flavanone)](PF6)2 and [(eta6-biphenyl)Ru(eta6-flavanone)](PF6)2. Although the complexes are very similar in structure, the first displayed moderate cytotoxic activity against both A2780 and A549 cancer cells (IC50 30 – 40 microns), which may be a result of an observed DNA interaction, while the second was selectively highly cytotoxic towards A549 cancer cells (IC50 ~ 6 microns) and showed no evidence of targeting DNA. Moreover, antioxidant properties inherent to the ligands were found to be enhanced on metal binding, giving the complexes additional potential in applications for the prevention of cancer. Significantly, this work has identified the first anticancer active metal bis-arene complexes of biologically-active ligands, therefore demonstrating the validity of such an approach to the design of novel drugs.
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Jami, Avinash. "Fused-Molecular Systems for Organic Light Emitting Diodes." TopSCHOLAR®, 2015. http://digitalcommons.wku.edu/theses/1543.
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Organic light emitting diodes (OLEDs) are electronic devices made by sandwitching organic light emissive materials between two electrodes. When voltage is applied across the two conductors, a bright light is generated. The color of the emitting light depends on the band gap of the semiconducting material. The work described here focuses on designing and synthesizing narrow band gap molecular systems derived from fused-arene derivatives for producing organic blue light emitting diodes. Three molecular systems derived from anthracene, pyrene, and carbazole, were designed and synthesized. Two molecular systems of anthracen-9-ylmethyl anthracene-9- carboxylate and pyren-1-ylmethyl 4-bromobenzoate were synthesized through Steglich esterification reaction and the third, pyren-1-ylmethyl 4-(9-hexyl-6-{4-[(pyren-1- ylmethoxy) carbonyl] phenyl}-9H-carbazol-3-yl) benzoate was synthesized by Grignard metathesis followed by Kumada coupling reaction. Structural characterizations were performed using 1H, 13C NMR and FTIR analysis. Photophysical properties of these systems were studied in chloroform (CHCl3) solution using UV-visible and Fluorescence spectroscopies. The absorption and fluorescence emission spectra revealed the potential applicability of these three systems as blue and blue-green emitters for OLEDs. The future work of this project will focus on utilizing these three molecular systems to fabricate OLED devices.
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Jefferson, Gary Robert. "Synthesis and reactivity of enantiomerically enriched (arene) tricarbonyl chromium (0) complexes." Thesis, Imperial College London, 1997. http://hdl.handle.net/10044/1/11404.
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Coen, Gerard Patrick. "Enzyme-catalysed synthesis and applications of enantiopure alkene and arene diols." Thesis, Queen's University Belfast, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.343093.
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Dorrity, Michael R. J. "Crystallographic studies of relative and absolute stereochemistry in cycloadducts and arene metabolites." Thesis, Queen's University Belfast, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317502.
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Bowers, Nigel Ian. "Dioxygenase-catalysed formation of arene hydroxylation products and their application in synthesis." Thesis, Queen's University Belfast, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.361355.
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Heritage, Trevor W. "Aspects of arene-ethene photocycloadditions and thermal asymmetric reactions under high pressure." Thesis, University of Reading, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.293026.
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Noffke, Anna Louise. "Arene ruthenium(II) thiosemicarbazone complexes as anticancer agents." Thesis, University of Warwick, 2015. http://wrap.warwick.ac.uk/66956/.
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This thesis presents the synthesis and characterisation of thiosemicarbazones (TSCs) and their arene ruthenium complexes for the use as anticancer agents. Based on substituted benzaldehyde derivatives, 12 different TSCs were used as N,S-chelating ligands in 24 different ruthenium half-sandwich complexes. The variations in their general structure [(p-cymene)Ru(RTSC)Z]+[A] include the use of both chloride and iodide as monodentate Z ligand. Iodine substituents in the TSC (R = I) were used to introduce a possible tracer moiety. Structure and reactivity elucidations by NMR, ESI-MS and X-ray absorption spectroscopy in Chapters 2 and 3 include the 15N-NMR chemical shift determination for the 12 TSCs by 1H15N-HMBC NMR in solution. The TSC imino (N1) and the hydrazinic (N2) nitrogen atoms exhibit significant 15N-NMR chemical coordination shifts of -60 ppm and +122 ppm, respectively. The latter indicates deprotonation of the NH in solution. X-ray crystal structures of two complexes are presented, for [(p-cymene)Ru(PTSCNMe2)][PF6] and for the dinuclear complex [(p-cymene)Ru(DTSCIPh)]2[PF6]2. The crystallographic data were used as models for theoretical stting of Ru K-edge EXAFS data. The EXAFS fits to data obtained for the presented complexes strongly match the first coordination sphere found in the crystal structure of complex. Solution-state XAS on freeze-quenched aliquots of a solution of [(p-cymene)Ru(DTSCNMe2)Cl]Cl confirm its conversion into. [(p-cymene)Ru(PTSCNMe2)I]PF6 and [(p-cymene)Ru(ITSCNMe2)I]PF6 with an iodine substituent are investigated in Chapter 4. Both have antiproliferative activity (IC50 = 2 M) against human ovarian cancer cells (A2780) , causing cell-cycle arrest in G1-phase and induction of apoptotic pathways. The strategic positional variations of iodine labels within this series combined with the simultaneous detection of 101Ru and 127I by ICPMS showed that the monodentate ligand Z does not enter the cancer cells. In contrast to this, the aromatic iodine substituent in the TSC ligand of [(p-cymene)Ru(R-TSC)I]+ enhances cellular accumulation of both ruthenium and TSC-bound iodine, but not the cytotoxicity of the complex.
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Zou, Yan. "Study of Lone Pair-Arene Interactions in Solution." Miami University / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=miami1186024674.
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Gradwell, Kate. "Modified calix[4]arene receptors for anion and cation recognition." Thesis, University of Oxford, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.360297.
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Blakemore, David C. "The intramolecular meta photocycloaddition of heteroatom containing non-conjugated arene-ethene bichromophoric systems." Thesis, University of Reading, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.359098.
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Bhambri, Sameer. "Ruthenium arene poly(pyrazolyl)borates and methanes : synthesis, reactivity and molecular orbital calculations." Thesis, University College London (University of London), 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.300010.
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