Dissertations / Theses on the topic 'Aryl Compounds'
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1
Leyva-Ramos, Elisa. "The temperature dependent photochemistry of aryl azides and aryl diazo compounds /." The Ohio State University, 1986. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487267024997622.
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Leary, Edmund. "Single Molecule Conductance of Dithiahexyl-Aryl Compounds." Thesis, University of Liverpool, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.507724.
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Ross, Jennifer Nicola. "Alkoxy- substituted aryl- and benzyl- organotin compounds." Thesis, University of Aberdeen, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.324880.
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New organotin compounds containing alkoxy- functionalities have been prepared. The methods of preparation of the tetraorganotin species have involved three routes. Hydrostannation reactions using triphenyltin hydride have resulted in the synthesis of triphenyltin derivatives of a series of alkoxy- substituted allyl ethers. The addition of tin IV chloride, diphenyltin dichloride and phenyltin trichloride to alkoxy- substituted aryl- and benzyl- Grignard reagents have also been successful. Alkoxy- substituted benzyltin compounds have been prepared by following an alternative preparation of benzylmagnesium halides from that commonly used to prepare Grignard reagents. Nucleophilic substitution of (iodomethyl)triphenyltin by a novel ligand has been effective. The structures of the products have been investigated by 1H, 13C and 119Sn nmr. Single crystal X-ray diffraction studies have led to the determination of the crystal structures of tetra-2-anisyltin, tetrakis-(2-methoxybenzyl)tin and N,N'-bis(5-triphenylstannoxymethyl-2-phenyl-1,3-dioxan-5-yl)ethanediamide. Selective tin-carbon bond cleavage has been effected by the use of iodine and bromine to give rise to mono- and dihalo- organotin compounds and the crystal structures of tri-2-anisyltin iodide and di-2-anisyltin dibromide have been elucidated by X-ray crystallography. Chloro(3-ethoxypropyl)diphenyltin has been synthesised directly from diphenyltin dichloride and has been found to contain a penta-co-ordinate tin centre with a four membered chelate ring as a result of intramolecular tin-oxygen co-ordination. Other tin-carbon bond cleavage reactions by halogens have been studied by 1H and 119Sn nmr and GLC and the results discussed.
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Khashoqji, Moayad. "Structural characterisation of novel poly-aryl compounds." Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/structural-characterisation-of-novel-polyaryl-compounds(3fb1fac6-548a-4afc-8ac2-5a14885b0ba4).html.
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Poly-aryl, also known as polyphenylene compounds are a class of dendrimer, which contain a large number of aromatic rings. They are of interest because they display restricted rotation of their stearically congested aromatic rings. These extended structures have the potential to act as precursors for even larger aromatic systems and have many applications including electronic devices, drug delivery and catalysis. A total of 23 novel poly-aryl compounds have been examined using single crystal X-ray diffraction and a number of structural patterns have emerged. Six of the compounds contain alkynes and it has been observed that their conformation is governed by a combination of conjugation between the alkyne and aryl groups and inter-molecular interactions. In the more extended poly-aryl compounds steric congestion rules out any possibility of conjugation between the rings and their conformation is governed by intra-molecular non-bonded interactions in the core of the molecules and by inter-molecular interactions in their periphery. Where possible, solution NMR measurements were carried out on the poly-aryl compounds and confirmed that the solution structures are in agreement with those obtained from individual crystal.
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Rowland, Keith E. (Keith Edward). "An NMR Investigation of Aryl Mercury Compounds." Thesis, North Texas State University, 1987. https://digital.library.unt.edu/ark:/67531/metadc500453/.
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A variable temperature ^13 C and ^199 Hg NMR study has been conducted for diphenyl-, bis(o-tolyl)-, bis(m-tolyl)-, and bis(2, 6-xylyl)mercury in dimethyl sulfoxide and 1,1,2,2 tetrachloroethane; ^13 C T1 relaxation times are reported as a function of temperature. Barriers to rotation of the aryl rings are obtained. Chemical shifts and couplings in CDCl_3 are given for bis(p-tolyl)-, bis(2, 5-xylyl)-, bis(mesityl)-,phenyl(o-tolyl)-, phenyl(m-tolyl)mercury, and the compounds listed above. The steric interactions of these aryl mercury compounds are discussed.
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Guena, Thierry. "Electrochemistry of aryl carbonyl compounds in flow cells." Thesis, University of Southampton, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.243180.
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Heaton, Julie N. "Generation and reactions of aryl and alkyl thionitroso compounds." Thesis, Durham University, 1992. http://etheses.dur.ac.uk/6129/.
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Transient thionitrosoarenes (102) with para substituents have been generated from N-(arylaminothio)-phthalimide derivatives (101) and intercepted with chloroprene and piperylene to give regioisomeric Diels- Alder adducts. Reaction of thionitrosoarenes (102) with 1-methylcyclohexene, a-pinene and β-pinene gave sulphenamides. Sulphenamides (110) and(123) have been reacted with 2,6-difluorobenzoylisocyanate. Heteroaryl thionitroso compounds have been prepared. Thionitrosoarenes with an ortho substituent have been generated via two different routes and trapped with 2,3-dimethyl-l,3-butadiene to give mixtures of Diels-Alder and ene adducts; the ene adduct was the major isomer for each system. Thionitrosoarene (159b) was generated from 3- aminobenzisothiazole (157b) using lead tetraacetate and was intercepted with 2,3-dimethyl-l,3-butadiene to give Diels-Alder (160) and ene (161) adducts. Thionitrosoalkanes have been generated using two different routes and trapped with 2,3-dimethyl-l,3-butadiene to give Diels-Alder and ene adducts.
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Aprahamian, Steve Lawrence. "Rearrangement-displacement of aryl(chloromethyl)diphenylsilanes with nucleophiles /." The Ohio State University, 1986. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487265555439529.
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Al-Harthy, Farida. "Separation of aryl nitro-compounds by HPLC on monolithic columns." Thesis, Loughborough University, 2009. https://dspace.lboro.ac.uk/2134/8683.
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The project has demonstrated the use of both poly(styrene-divinylbenzene) PS-DVB and silica monolithic columns for the separation of nitro-compounds. Methods were developed with PS-DVB and ODS silica packed columns for the separation of these compounds. The first part of the project was the preparation of the monolithic stationary phases prepared from PS-DVB of (250 μm I.D. × 70 mm) functionalized with methacrylate by in-situ polymerisation. The alkylated PS-DVB then was used successfully for the first time in the separation of three aryl nitro-compounds (2-NA, 1,4-DNB and 4-NT) on micro-HPLC. However, the efficiency of this column was poor N = 318 (4675/m).The second part of the thesis used a commercial column (Chromolith Performance from Merck), with different diameters for the separation of nitro-compounds. Nitrocompounds were analysed on both Chromolith Performance 3 mm I.D. column and Chromolith Performance 4 mm I.D. column by HPLC/UV. Van Deemter plots showed that the 3 mm I.D. column gave higher efficiencies at higher flow rates than the 4.6 mm I.D. column. The plate number was 8216 (H = 0.0121 mm) at a flow rate of 0.4 ml/min (1.0206 mm/sec) and for Chromolith 4.6 mm I.D. it was 9436 (H = 0.0105 mm) at a flow rate of 0.8 ml/min (0.8577 mm/sec). The nitro-compounds analysed in this study were nitroaromatic, nitramines and nitrate esters which are used in the manufacture of explosives. These compounds were analysed for the first time using a Chromolith Performance 3 mm I.D. column on LCMS using both ESI and APCI in negative ionization modes. The sensitivity was higher in the APCI than the ESI mode in terms of higher intensity and lower background noise especially for nitroaromatic compounds. The LC-ESI-MS method was evaluated by injection of samples of pentaerythritol tetranitrate (PETN) in different concentrations. Calibration curves were constructed over the range of 1-1000 pg/μl with a correlation coefficient of (R2 = 0.9986) and with a concentration range between 1-200 ng/μl with a correlation coefficient of (R2 = 0.9971) and were found to be linear. The limit of detection (LOT) for pentaerythritol tetranitrate (PETN) was 5 pg/μl at a signal-to-noise ratio (S/N) of 3:1 and the limit of quantification (LOQ) was 10 pg/μl at a signal-to-noise ratio of 10:1. The applicability of the monolithic column for the LC-ESI-MS method was evaluated by injection of samples of the commercial explosives, P9 and Semtex 1H. The results showed that Semtex 1H contains 35% PETN using calibration curve 1-200 ng/μl and was much higher than in P9 0.0082% using calibration curve 1-1000 pg/μl.
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Ng, Fei-yeung, and 吳飛洋. "Structure and properties of self-assembled coordination compounds: homoleptic d10-metal aryl/alkylacetylides, ruthenium n-heterocyclesand picolinates." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B37878566.
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Ng, Fei-yeung. "Structure and properties of self-assembled coordination compounds : homoleptic d10-metal aryl/alkylacetylides, ruthenium n-heterocycles and picolinates." View the Table of Contents & Abstract, 2006. http://sunzi.lib.hku.hk/hkuto/record/B36587126.
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Khan, Imtiaz. "Enolate-directed catalytic C-H functionalization of 2-aryl-1,3-dicarbonyl compounds." Thesis, University of Nottingham, 2015. http://eprints.nottingham.ac.uk/30261/.
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I) Synthesis of Spiroindenes by Enolate-Directed Ruthenium-Catalyzed Oxidative Annulation of Alkynes with 2-Aryl-1,3-dicarbonyl Compounds The synthesis of carbocycles by the ruthenium-catalyzed oxidative annulation of alkynes with 2-aryl cyclic 1,3-dicarbonyl substrates is described. Proceeding by the functionalization of C(sp3)–H and C(sp2)–H bonds, and the formation of all-carbon quaternary centers, the reactions provide a diverse range of spiroindenes in good yields and high levels of regioselectivity. II) Synthesis of Benzopyrans by Pd(II)- or Ru(II)-Catalyzed C–H Alkenylation of 2-Aryl-3-hydroxy-2-cyclohexenones We have explored the 2-aryl-3-hydroxy-2-cyclohexenones as competent substrates for palladium- and ruthenium-catalyzed C–H alkenylation reactions with terminal alkenes. This process affords benzopyrans, in most cases, with good functional group tolerance. III) Synthesis of Spiroindanes by Palladium-Catalyzed Oxidative Annulations of 1,3-Dienes Involving C–H Functionalization 1,3-Dienes have been an underexplored class of substrates in catalytic oxidative annulation reactions involving C‒H functionalization. The synthesis of spiroindanes by the palladium-catalyzed oxidative annulation of 1,3-dienes with 2-aryl cyclic 1,3-dicarbonyl compounds is described. Several examples of the dearomatizing oxidative annulation of 1,3-dienes with 1-aryl-2-naphthols are also presented. IV) Enantioselective Spiroindene Formation via C‒H Functionalization Using Chiral Cyclopentadienyl Rhodium Catalysts A chiral cyclopentadienyl rhodium ligand with an atropchiral biaryl backbone enables an asymmetric synthesis of spiroindenes from 2-aryl-1,3-dicarbonyl compounds and alkynes. The process affords a range of products with all-carbon quaternary center in high yields and excellent enantiselectivities. The good functional group tolerance and broad substrate generality are the advantages of this reaction.
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楊小雯 and Siu-man Yeung. "The synthesis and reactions of 3H-pyrroles bearing methyl and aryl groups." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1991. http://hub.hku.hk/bib/B31210119.
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Otsuka, Shinya. "Studies on Catalytic Transformations of Organosulfur Compounds via C-S Bond Cleavage." Kyoto University, 2019. http://hdl.handle.net/2433/242625.
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Wieczysty, Martin David. "C-H functionalisation of 2-aryl cyclic 1,3-dicarbonyl compounds ; Enantioselective Rh(I)-catalysed cyclisation of arylboron compounds onto ketones." Thesis, University of Edinburgh, 2015. http://hdl.handle.net/1842/18741.
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1. C–H Functionalisation of 2 Aryl Cyclic 1,3-Dicarbonyl Compounds Two enolate-directed C–H functionalisation protocols have been developed using 2-aryl cyclic 1,3-dicarbonyl compounds as substrates. Reactions with activated alkenes, under ruthenium or palladium catalysis produced benzopyrans in most cases, in moderate to good yield. Alternatively, an oxidative annulation of 2-aryl cyclic 1.3-dicarbonyls with 1,3-enynes was facilitated under rhodium catalysis, forming functionalised spiroindene structures in most cases, in generally good yields and high regioselectivity. During the investigation, the serendipitous formation of spirodialin structures was also observed. 2. Enantioselective Rh(I)-Catalysed Cyclisation of Arylboron Compounds onto Ketones Chiral tertiary alcohols, bearing aza-, oxa- and carbocyclic core structures of varying ring size were successfully formed from arylboron substrates under rhodium catalysis. In general the reactions proceeded with good yield and with moderate to high enantioselectivity. A protocol for the formation of a bicyclic lactam system was also achieved in moderate yield and enantioselectivity.
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Tatton, Matthew R. "New methods for the synthesis of aromatic compounds." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:52a95189-d8ea-432f-aefd-4f9ae7ef996a.
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Introduction The introduction describes the importance of arylamine compounds to society and provides a brief overview of the methods available for their synthesis. The application of metathesis catalysis to the de novo synthesis of heteroaromatic compounds is also described. Results and discussion The first section describes efforts towards the de novo synthesis of arylamines using a cross metathesis/oxidation protocol to form a 1,5-unsaturated dicarbonyl followed by an amine mediated cyclisation. The scope with respect to the 1,5-unsaturated dicarbonyl and amine is covered as well as the utility of some of the products. The section concludes with a modification of the Bohlmann Rahtz pyridine synthesis to furnish arylamines. The next section describes the applications of our methodology to the synthesis of naphthylamines, specifically using the palladium catalysed α-arylation reaction. A discussion of the α-arylation reaction is included as well as our efforts to explore the scope of the reaction. The third section follows our efforts to apply this methodologyy to the synthesis of five benzo[c]phenanthridine alkaloids including the first reported synthesis of maclekarpine B and C. The final section concludes with a discussion of our efforts towards the de novo synthesis of furans bearing a benzylic stereocentre.
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Baeza, Mario Ivan. "Synthesis and characterization of acetylenic derivatives of the actinide extractant (aryl)-N,N-di-(alkyl)carbamoylmethylphosphine oxide (CMPO)." To access this resource online via ProQuest Dissertations and Theses @ UTEP, 2008. http://0-proquest.umi.com.lib.utep.edu/login?COPT=REJTPTU0YmImSU5UPTAmVkVSPTI=&clientId=2515.
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Libot, Cecile. "The influence of cathode material on the reduction of aryl carbonyl compounds : formation of radicals." Thesis, University of Southampton, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.313211.
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Mohammad, Reza Farmahin Farahani. "Prediction of the Sensitivity of Avian Species to the Embryotoxic Effects of Dioxin-like Compounds." Thèse, Université d'Ottawa / University of Ottawa, 2013. http://hdl.handle.net/10393/23696.
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The main goal of this thesis was to develop new methods and knowledge that will explain and predict species differences in sensitivity to dioxin-like compounds (DLCs) in birds. The important achievements and results obtained from the four experimental chapters of this thesis are summarized as follow: (1) an efficient luciferase reporter gene (LRG) assay was developed for use with 96-well cell culture plates; (2) the results obtained from LRG assay were shown to be highly correlated to available in ovo toxicity data; (3) amino acids at positions 324 and 380 within the aryl hydrocarbon receptor 1 ligand binding domain (AHR1 LBD) were shown to be responsible for reduced Japanese quail (Coturnix japonica) AHR1 activity to induce a dioxin-responsive reporter gene in comparison to chicken (Gallus gallus domesticus), and ring-necked pheasant (Phasianus colchicus) AHR1 in response to different DLCs; (4) AHR1 LBD sequences of 86 avian species were studied and differences at amino acid sites 256, 257, 297, 324, 337 and 380 were identified. It was discovered that only positions 324 and 380 play a role in AHR1 activity to induce a dioxin-responsive gene; (5) in COS-7 cells expressing chicken AHR1, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and 2,3,4,7,8-pentachlorodibenzofuran (PeCDF) are equipotent inducers of the reporter gene and bind with similar affinity to chicken AHR1, however, in the cells expressing pheasant, Japanese quail and common tern (Sterna hirundo) AHR1, PeCDF is a stronger inducer than TCDD. PeCDF also binds with higher affinity to pheasant and quail AHR1 than TCDD.
The results of this thesis show that embryo lethal effect of DLCs in avian species can be predicted by use of two new non-lethal methods: (1) the LRG assay and (2) determination of the identity of the amino acids at positions 324 and 380. The findings and methods described in this thesis will be of use for environmental risk assessments of DLCs.
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Sriramulu, Phenahas Gandu. "On-Metal Synthesis of Some Aryl Substituted Rhenium ┫ Cyclopenta[C] Pyridazyl Complexes." TopSCHOLAR®, 2010. http://digitalcommons.wku.edu/theses/197.
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Heterocyclic organic and organometallic compounds (e.g. polypyrrole) and their derivatives have been of great interest for conductive polymers due to their novel properties and environmental stability as compared to non-aromatic analogs (e.g. polyacetylene). We are interested in synthesizing organometallic pyridazines and rhenium pyridazyl complexes for polymer research. SeveraI5,6-fused ring pyridazines (1,2-CsH3(CRNH)(CRN) have been synthesized and characterized. Additionally, pyridazyl complexes of rhenium were synthesized in three steps beginning from fulvenes 1,2-CsH3(COHR)(COR). On-Metal synthesis and characterization of (Re(CO)3 {1,2- CSH3(CRN)(CRN)}] (R=C6RtOMe, C6RtCI, C4H30) and some off-metal pyridazines are reported here. Our research is focused on synthesis of a variety of 5,6- fused ring pyridazines which will serve as synthetic models and building blocks for organic and organometallic conducting polymers.
Our research focused on synthesis of 5 membered pyridazines and their organometallic rhenium complexes for polymer studies. Several aryl-substituted 5,6- fused ring pyridazines have been synthesized and characterized.
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Li, Wanfei. "Chemical synthesis of anti-HIV compounds based on the aryl naphthalene lignans identified from justicia plants." HKBU Institutional Repository, 2019. https://repository.hkbu.edu.hk/etd_oa/685.
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Background: Natural products have been a rich source for the discovery of lead compounds in modern drug discovery. 6,7'-Cyclolignans are a class of secondary metabolites which are widely distributed in more than 20 families. This important class of lignans continue to attract the interest of the pharmaceutical industry owing to their remarkable biological benefits, particularly for their anti-tumor and antiviral properties. Arylnaphthalene lignans (ANLs) belong to 6,7'-cyclolignans which contain a 2,3-dimethyl-1-phenyl-naphthalene core structure. ANLs are widely distributed in plants. Justicia cf. patentiflora was identified as an anti-HIV (human immunodeficiency virus) plant lead through the screening of more than 3,500 plant extracts. Bioassay-directed fractionation of the methanol extract of the stems and barks of this plant has led to the isolation of three ANL glycoside compounds, which displayed potent inhibitory activity against broad HIV clinical strains with EC50 values in the range of 14-37 nM [Zidovudine (AZT): 77-95 nM]. They also showed significant inhibitory effects against drug-resistance HIV strains. Thus, the ANL glycosides have high potential as lead molecules for the development of new therapeutic drugs for HIV/AIDS. Objectives: 1) To establish an efficient route for the total synthesis of ANL compounds and to synthesize a library of ANL compounds through the established total synthetic approach; 2) To evaluate the cytotoxicities and anti-HIV activities of the synthesized ANLs; 3) To elucidate the structure activity relationship (SAR) of ANLs as a basis for the optimization of drug efficacy, improvement of pharmacokinetic properties as well as minimization of the toxicity of ANLs; 4) To synthesize potent anti-HIV ANL molecules with high selectivity. Methods: To achieve these objectives, a synthetic route for ANL was designed and a broad series of ANL derivatives were synthesized via modifications of rings A and B, as well as the functionalities at C-7. The synthesized compounds had been evaluated for their toxicity and antiviral activities. Cytotoxicity was determined using the SRB (Sulforhodamine B) assay, while anti-HIV activity was evaluated by utilizing the "One-Stone-Two-Birds" protocol. Results: We have accomplished the total synthesis of the key intermediate diphyllin with more than 20 g. Our modification of ANL derivatives focused on substitutions, additions and different configurations of the C-7 position, ring A and ring B. Specifically, the different structural components of the ANLs were systematically modified, resulting in the formation of six groups of compounds. A total of 72 ANL compounds with various functional groups were synthesized. Their structures have been confirmed by the MS and NMR spectral data. All the synthesized ANL compounds were purified to have purity ≥ 95%. The SAR of ANL compounds was revealed based on the analysis of the antiviral and cytotoxicity data of these synthetic analogues. After structural modification, all the modified derivatives based on rings A and B (groups 1 and 2) showed activity reduction in terms of both cytotoxic and anti-HIV activities. However, the modification of C-7 yielded divergent results, which included the groups of 3-6. Most compounds in groups 3-5 displayed comparable inhibitory effect with diphyllin (5). Group 6 represents the largest number of analogues among the six groups. In this group, the stereochemical properties and functionalization of the hydroxy groups on the sugar units are essential for their activities. Among these series of derivatives, compound 17b showed significant high potency of anti-HIV activity with an EC50 value of 2.6 nM and SI of 815. Conclusion: Using the synthesized diphyllin as the key intermediate, a compound library of 72 ANL derivatives was obtained. These compounds have been evaluated for their cytotoxicity and anti-HIV activity. Our bioactivity data revealed that the functionalization of the C-7 hydroxy group could significantly reduce the cytotoxicity and increase anti-HIV activity, while the modification on rings A and B would rather result in the reduction of both cytotoxicity and anti-HIV activity. Subsequently, novel diphyllin glycosides containing various sugar moieties were further synthesized. Several of these ANL analogues showed high anti-HIV activity with EC50 values in the nM range and low cytotoxicity (selective indices > 500). Future Perspective: This study clearly suggests ANLs as anti-HIV lead compounds and they have high potential to be developed as therapeutic drugs for the treatment of HIV. To further confirm the antiviral potential of ANLs, live HIV strains including some drug resistant strains should be further investigated. Although our data have shown that the ANL compounds are targeting the viral post-entry stages, their antiviral molecular targets are still unknown. However, since our SAR information has clearly revealed that the substitution of rings A and B are not involve in the antiviral activity for enhancing ANL compounds, the carbon positions in these rings may be explored to link a biotin unit, which can be used as a viable approach to pull down the antiviral target proteins of ANLs. Once the target proteins are identified, molecular docking is then made possible for a rational synthetic design to fine tune the chemical structures of ANLs in order to improve their antiviral properties such as high antiviral activity, low toxicity and enhanced water solubility. A further step to advance ANLs as anti-HIV drugs is the investigation of their drug properties in in vivo studies including the assessment of their anti-HIV efficacy in the rhesus model as well as obtaining their pharmacokinetic and safety parameters. These studies will help to provide more evidence about the anti-viral properties of ANLs
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Angulo-Escalante, Miguel Angel 1962. "Inhibition of thioredoxin signalling by alkyl and aryl 2-imidazolyl disulfide compounds as potential antitumor agents." Diss., The University of Arizona, 1998. http://hdl.handle.net/10150/282694.
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This work describes (1) the identification of alkyl and aryl 2-imidazolyl disulfides that inhibit growth in human cancer cell lines, (2) examines the antitumor activities of these disulfides in xenografted scid mice, (3) characterizes the chemopreventive activity in min mice of the disulfides IV-2, and (4) suggests the potential mechanisms by which these compounds mediate their actions. The alkyl and aryl 2-imidazolyl disulfides are inhibitors of the TR/Trx which regulates cell growth in both normal and cancer cells and is constitutively activated in a number of human primary cancers (Berggren, 1996). We found that all of the disulfides tested were potent inhibitors of growth in a panel of 60 cancer cell lines tested by the NCI. Disulfides IV-2, VI-2, and DLK-36 were found to inhibit growth of HL-60 leukemia and MCF-breast cancer cells implanted in scid mice. However, these disulfides had no significant inhibitory effect on the growth of human HT-29 colon cancer cells implanted in scid mice. Disulfide IV-2 also demonstrated a chemopreventive activity evaluated in min mice fed diet supplemented with 250 ppm IV-2. These disulfides may function through modulation of cellular redox status. It was determined that disulfides IV-2 and DLK-36 decreased GSH levels and that this effect may be due to indirect inhibition of the TR/Trx redox system or a direct reaction of GSH with the disulfides. Importantly, Human Trx regulates transcription factors such as NF-KB and activation of this transcription factor protects cells from apoptosis. Disulfide IV-2 was observed to inhibit the transcriptional activity of NF-KB. This inhibitory activity may sensitize cells to apoptosis. Most of the disulfides tested induced apoptosis at concentrations of twice the IC50 in both MCF-7 breast and HT-20 colon cancer cells. Interestingly, a protein which is secreted by MCF-7 cells into the media can degrade disulfide IV-2. This putative molecule has a molecular weight (m.w) greater than 3000 and is likely redox sensitive because ultra-filtered conditioned media (3000 m.w.) or aged media drastically decreased the degradation or sequestration activity of conditioned media. Plasma from mice treated with disulfides IV-2 or DLK-36 (i.v.) gave the same HPLC profile as seen in in vitro studies. These disulfides could be inhibiting tumor growth by inhibition of the TR/Trx system and/or depletion of GSH. Finally, the p53 tumor suppressor protein appears to be regulated by redox conditions. Recent, evidence suggests p53 may be regulated specifically by the TR redox system. The rat embryo fibroblast cell line, Al-5, expressing wild-type p53 was less sensitive to disulfides than these same cells expressing mutant p53.
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Jayatissa, Kuruppu Lilanthi. "A Metal-Free Approach to Biaryl Compounds: Carbon-Carbon Bond Formation from Diaryliodonium Salts and Aryl Triolborates." PDXScholar, 2015. https://pdxscholar.library.pdx.edu/open_access_etds/2229.
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Biaryl moieties are important structural motifs in many industries, including pharmaceutical, agrochemical, energy and technology. The development of novel and efficient methods to synthesize these carbon-carbon bonds is at the forefront of synthetic methodology. Since Ullmann’s first report of stoichiometric Cu-mediated homo-coupling of aryl halides, there has been a dramatic evolution in transition metal catalyzed biaryl cross-coupling reactions.
Our work focuses on the discovery and development of an unprecedented reagent combination for metal-free cross-coupling. It is hypothesized that direct carbon-carbon bond formation occurs via a triaryl-λ3-iodane and that electrophile/nucleophile pairing is critical for success in the reaction. Proof-of-concept for this approach focused on the reaction between bromo 4-trifluoromethylphenyl (trimethoxybenzene)-λ3-iodane and potassium 3-fluorophenyltriolborate. The spectator ligand and counter ions are important parameters for both reactivity and selectivity of the aryl group transfer in this reaction. Moderate to good yields of biaryl products are obtained by this method. Experimental evidence supports the assertion of a metal-free cross-coupling reaction.
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Zhang, Ye. "Development of amide-derived P,O-ligands for Suzuki cross-coupling of aryl chlorides and the asymmetric version /." View abstract or full-text, 2005. http://library.ust.hk/cgi/db/thesis.pl?CHEM%202005%20ZHANG.
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Meyer, Andreas Uwe [Verfasser], and Burkhard [Akademischer Betreuer] König. "Organic Photoredox Catalysis: Oxidation of Sulfur Containing Compounds and Reduction of Aryl Halides / Andreas Uwe Meyer ; Betreuer: Burkhard König." Regensburg : Universitätsbibliothek Regensburg, 2018. http://d-nb.info/1159375747/34.
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Rahman, Obaidur. "[11C]Carbon Monoxide and Aryl Triflates in Palladium-Mediated Carbonylation Reactions : Synthetic approaches to [11C]Carbonyl Compounds and [11C]Amines." Doctoral thesis, Uppsala universitet, Kemiska institutionen, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-4157.
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The usefulness of low concentrations (typically 10 to 100 µM) of [11C]carbon monoxide and aryl triflates as substrates in 11C-carbonylation using different nucleophiles in the presence of lithium bromide was investigated. The reactions were performed in a micro autoclave of 200 µL volume and catalysed (mediated) by palladium(0). A peripheral type benzodiazepine receptor (PBR) ligand, 1-(2-chlorophenyl)-N-methyl-N-(1-methylpropyl)isoquinoline-3-carboxamide (PK11195) and its structural analogues including an irreversible ligand for PBR, some other amides, ketones and carboxylic acids, were all labelled with 11C using this approach. The [carbonyl-11C]PK11195, analogues and other amides were prepared from aryl triflates and amines, and the [carbonyl-11C]ketones were prepared from aryl triflates and organoboranes. In the synthesis of [carboxyl-11C]carboxylic acids, water was utilised as nucleophile. The decay-corrected radiochemical yields were 10 to 55% for [11C]PK11195 and analogues, 2 to 63% for other [11C]amides, 10 to 75% for [11C]ketones and 25 to 65% for [11C]carboxylic acids. The specific radioactivity of the labelled compounds was in the range of 150 to 900 GBq/µmol. Some [11C]amines were prepared by a reductive amination of the corresponding [carbonyl-11C]ketones. These reactions were performed using different amines in the presence of TiCl4 and NaBH3CN. The radiochemical yields of the [11C]amines varied from 2 to 78% (determined by analytical HPLC). In order to confirm the labelling position, synthesis of selected 13C-substituted compounds were performed. For each substance group/ synthesis method, a selected compound was synthesised using (13C)carbon monoxide and the 13C-substituted compound was then analysed by 13C NMR. A synthetic route was developed for the preparation of 1-(2-chloro-phenyl)-isoquinolin-3-yl trifluoromethanesulfonate used as the precursor in the synthesis of [carbonyl-11C]PK11195 and analogues.
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Urgin, Karene. "Préparation de dérivés aryl- et hétéroaryl- pyridazine(s) par voies organométalliques chimiques ou électrochimiques." Thesis, Paris Est, 2010. http://www.theses.fr/2010PEST1094.
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Les hétérocycles aromatiques sont des motifs structuraux rencontrés dans un grand nombre de substances d'intérêts biologiques ou pharmacologiques. Plus particulièrement, les pyridazines substituées font l'objet d'un intérêt grandissant pour leurs propriétés pharmaceutiques (antibactériens, anti-inflammatoires, médicaments cardiovasculaires…). De plus, les structures comportant des pyridazines peuvent également être utilisées en tant qu'agents chélatants de cations métalliques et s'ordonner en édifices utilisés en chimie supramoléculaire.Nous nous sommes donc intéressés à l'élaboration d'éléments de base comportant des cycles pyridaziniques de type aryl ou hétéroarylpyridazines. La mise au point de méthodes impliquant des espèces organométalliques a été l'un de nos objectifs primordial. L'élaboration de ces composés a été réalisée par formation de liaisons C-C. Une approche électrochimique d'hétérocouplage associé à une catalyse au nickel a été utilisée. Quelques limites à cette méthode ont cependant été observées dans le cas des couplages mettant en jeu des 3,6-dihalogénopyridazines. Une étude par électrochimie analytique a permis d'en comprendre les raisons. La seconde partie de notre travail a consisté en l'étude de la réactivité d'arylzinciques ou de triarylbismuths vis-à-vis de 3,6-dihalogénopyridazinesHeteroaromatic rings are present in various biological and pharmacological active molecules. Substituted aryl-pyridazines have given rise to considerable interest because of their diverse pharmacological properties (antibacterial, anti-inflammatory, cardiovascular drugs…). Moreover, structures which contain pyridazines are used in supramolecular chemistry for their applications through self-assembly processes in the presence of metal ions.In order to elaborate building blocks containing pyridazine rings such as aryl or heteroaryl-pyridazines, we turned our intention on the development of complementary methods involving organometallic reagents. Transition metal-catalyzed cross-coupling reaction of organometallic compounds with organic halides is one of the most powerful methods for the generation of C-C bonds.We chose to develop the most straightforward method involves heterocoupling reaction of aryl/heteroaryl compounds under electrochemical conditions (sacrificial anode process) associated to a nickel catalysis. However some limitations have been pointed out when 3,6-dihalogenopyridazines are involved in the cross-coupling reaction. An electrochemical study was investigated in order to propose some mechanistic considerations. A second part of this work consisted in the study of arylzinc and triarylbismuths reagents toward 3,6-dihalogenopyridazines
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Perry, Philip J. "Synthesis and biological evaluation of novel cytotoxic heterocylic compounds : furo[2,3-b]naphthoquinones and 2-aryl-4H-3,1-benzoxazin-4-ones." Thesis, De Montfort University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.391202.
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Cui, Chunming. "Aluminum (I, II, III) Compounds with Multidentate Ligands: Syntheses, Reactivity, and Structures." Doctoral thesis, [S.l. : s.n.], 2001. http://webdoc.sub.gwdg.de/diss/2001/cui/cui.pdf.
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Lindstedt, Erik. "Metal-Free O- and C-Arylation with Diaryliodonium Salts." Doctoral thesis, Stockholms universitet, Institutionen för organisk kemi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-140944.
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This thesis concerns the development of metal-free applications using diaryliodonium salts. The first project describes an arylation protocol of allylic and benzylic alcohols in aqueous media. The method proceeds under mild conditions and the ether products were obtained in moderate to good yields. The methodology was also expanded to include arylation of phenols, giving diaryl ethers in good to excellent yields. In the second project, an arylation method that included a wider range of aliphatic alcohols was developed. The scope of accessible alkyl aryl ethers was studied and included a comparative study of phenylation and nitrophenylation of various alcohols. Finally, a formal metal-free synthesis of butoxycain was performed, illustrating the applicability of the developed method. The third project focused on the limitations and side reactions occurring in Chapter 2 and 3. First, an approach to access symmetric diaryl ethers via arylation of hydroxide was presented. This reaction gave rise to a number of side products, which we hypothesized to originate from aryne-type intermediates. A mechanism for the formation of these side products was suggested, supported by trapping and deuterium labeling experiments. Oxidation of the alcohol to the corresponding ketone was also observed and the mechanism of this interesting side reaction was investigated. The latter was suggested to proceed via an intramolecular oxidation without the involvement of radicals or arynes. The fourth project covers a method to synthesize highly sterically congested alkyl aryl ethers via arylation of tertiary alcohols using diaryliodonium salts. The method displayed a broad scope of tertiary alcohols and was also suitable for fluorinated alcohols. The final project detailed in this thesis deals with C-arylation with diaryliodonium salts, showcasing nitroalkanes as well as a nitro ester as suitable nucleophiles for metal-free arylation.At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 3: Manuscript.
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Walker, Kelcey Manae Becker. "Inhibitory actions of Ah receptor agonists and indole-containing compounds in breast cancer cell lines and mouse models." Texas A&M University, 2002. http://hdl.handle.net/1969.1/2433.
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The aryl hydrocarbon receptor (AhR) binds synthetic and chemoprotective phytochemicals, and research in this laboratory has developed selective AhR modulators (SAhRMs) for treatment of breast cancer. Activation of the AhR through agonists such as TCDD inhibits hormone activation of several E2-responsive genes in breast cancer cell lines. In this study, inhibition of E2-induced proliferation and gene expression by TCDD has been investigated in the uterus of wildtype, ERKO and AhRKO mice. Cyclin D1, DNA polymerase ?, and VEGF mRNA levels are induced by E2 through ER? in the uterus as determined by in situ hybridization studies. TCDD down-regulated E2-induced cyclin D1 and DNA polymerase ? expression, but not E2-induced VEGF expression, in wild-type mice, but not AhRKO mice, confirming the role of the AhR. Furthermore, protein synthesis was not necessary for induction of cyclin D1 or DNA polymerase ?gene expression by E2 or inhibition of these responses by TCDD. Therefore, AhR-ER? crosstalk directly regulates the expression of genes involved in cell proliferation in vivo.
AhR agonists induce down-regulation of ErbB family receptors in multiple tissues/organs suggesting possible inhibitory interactions with chemotherapeutic potential. Recently, it has been reported that the SAhRM 1,1??,2,2??-tetramethyldiindolylmethane inhibited DMBA-induced mammary tumor growth in rats and also inhibited MAPK and PI3-K pathways in human breast cancer cells. BT-474 and MDA-MB-453 cell lines are ErbB2-overexpressing breast cancer cells that express functional AhR and exhibit constitutive activation of MAPK and PI3-K pathways. Therefore, 1,1??,2,2??-tetramethyldiindolylmethane-induced inhibition of ErbB2 signaling was investigated in these cells lines and in the MMTV-c-neu mouse mammary tumor model, which overexpresses ErbB2 in the mammary gland. The growth of ErbB2 overexpressing cell lines and mammary tumors was inhibited by 1,1??,2,2??-tetramethyldiindolylmethane; however, modulation of MAPK or PI3-K pathways and cell cycle proteins nor induction of apoptosis by 1,1',2,2'-tetramethyldiindolylmethane was observed in the ErbB2overexpressing cell lines. Current studies are investigating mitochondrial effects of 1,1??,2,2??-tetramethyldiindolylmethane in the ErbB2-overexpressing cell lines, as well as continuing studies on gene expression profiles in the mammary glands of MMTV-c-neu mice to better understand and identify critical genes that are responsible for ErbB2-mediated transformation and growth of cancer cells/tumors.
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Larsson, Malin. "Computational methods for analyzing dioxin-like compounds and identifying potential aryl hydrocarbon receptor ligands : multivariate studies based on human and rodent in vitro data." Doctoral thesis, Umeå universitet, Kemiska institutionen, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-139487.
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Polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs) and polychlorinated biphenyls (PCBs) are omnipresent and persistent environmental pollutants. In particular, 29 congeners are of special concern, and these are usually referred to as dioxin-like compounds (DLCs). In the European Union, the risks associated with DLCs in food products are estimated by a weighted sum of the DLCs’ concentrations. These weights, also called toxic equivalency factors (TEFs), compare the DLCs’ potencies to the most toxic congener, 2,3,7,8-tetrachloro-dibenzo-p-dioxin (2378- TCDD). The toxicological effects of PCDD/Fs and PCBs are diverse, ranging from chloracne and immunological effects in humans to severe weight loss, thymic atrophy, hepatotoxicity, immunotoxicity, endocrine disruption, and carcinogenesis in rodents. Here, the molecular structures of DLCs were used as the basis to study the congeneric differences in in vitro data from both human and rodent cell responses related to the aryl hydrocarbon receptor (AhR). Based on molecular orbital densities and partial charges, we developed new ways to describe DLCs, which proved to be useful in quantitative structure-activity relationship modeling. This thesis also provides a new approach, the calculation of the consensus toxicity factor (CTF), to condense information from a battery of screening tests. The current TEFs used to estimate the risk of DLCs in food are primarily based on in vivo information from rat and mouse experiments. Our CTFs, based on human cell responses, show clear differences compared to the current TEFs. For instance, the CTF of 23478-PeCDF is as high as the CTF for 2378-TCDD, and the CTF of PCB 126 is 30 times lower than the corresponding TEF. Both of these DLCs are common congeners in fish in the Baltic Sea. Due to the severe effects of DLCs and their impact on environmental and human health, it is crucial to determine if other compounds have similar effects. To find such compounds, we developed a virtual screening protocol and applied it to a set of 6,445 industrial chemicals. This protocol included a presumed 3D representation of AhR and the structural and chemical properties of known AhR ligands. This screening resulted in a priority list of 28 chemicals that we identified as potential AhR ligands.
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Rahman, Obaidur. "[11C]Carbon Monoxide and Aryl Triflates in Palladium-Mediated Carbonylation Reactions : Synthetic approaches to [11C]Carbonyl Compounds and [11C]Amines." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-4157.
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Manoso, Amy Slover. "Hypercoordinate silicon compounds In organic synthesis improved methods for the synthesis of aryl(trialkoxy)silane derivatives ; and trimethylsilyl cyanide as a cyanide source for nucleophilic substitution /." College Park, Md. : University of Maryland, 2004. http://hdl.handle.net/1903/1664.
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Thesis (Ph. D.)--University of Maryland, College Park, 2004.Thesis research directed by: Chemistry. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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Milton, Edward J. "Pd catalysed C-C & C-O bond formation using bis-(dialkyl/diarylphosphino)ferrocene ligands." Thesis, University of St Andrews, 2010. http://hdl.handle.net/10023/1022.
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A brief introduction explaining phosphine ligand properties, Pd catalysed cross-coupling reactions; the importance of the steps involved in the catalytic cycle (oxidative addition, transmetalation & reductive elimination), mechanistic studies and a comparison of various reactions will give an overview of important cross-coupling reactions and their limitations. The development of a “super-concentrated” (5M) Pd catalysed Kumada type coupling reaction has been developed for coupling a range of aryl bromide and chloride substrates with the Grignard reagents ((p-CF₃-C₆H₄)MgBr)) and PhMgBr in methyl-tetrahydrofuran (Me-THF). Using a range of bidentate ligands such as bis-phosphinoferrocenyl ligands, good conversions were achieved using small amounts of solvent; up to 10 times less than typical procedures in THF. The unsymmetrical Pt complexes of the form [Pt(P-P)Br₂], [Pt(P-P)(Ph)Br] and [Pt(P-P)Ph₂] have been synthesised and characterised. The variations of substituents on the ligand system and the steric bulk have been shown to have a dramatic effect on the rate of transmetalation. The results provide one explanation why 1,1’-bis(di tert-butylphosphino)ferrocene (dtbpf), an excellent ligand for certain Suzuki reactions, is quite poor in reactions where transmetalation is more difficult. Palladium dichloride complexes of the ferrocenylphosphine based ligands 1,1’-bis- (diphenylphosphino)ferrocene (dppf), 1,1’-bis-(diisopropylphosphino)ferrocene (dippf) and 1,1’-bis-(di-tert-butylphosphino)ferrocene (dtbpf) have been shown to be active in the Hiyama cross-coupling of p-bromoacetophenone and vinyltrimethoxysilane (CHCH₂Si(OMe₃)) in the presence of TBAF under thermal heating and microwave conditions. Ligands with the optimum balance for promoting the transmetalation, oxidative addition and reductive elimination steps along the reaction pathway have been identified. Competition experiments are consistent with slow transmetalation being an issue with the Hiyama reaction relative to the Suzuki coupling. A novel protocol has been developed for the synthesis of aryl-alkyl ethers via C-O bond activation under Pd catalysed conditions. Utilising the unsymmetrical 1-bis-(ditertbutyl-1’- bis-diphenylphosphino)ferrocene (dtbdppf) under optimised conditions with silicon based nucleophiles and NaOH or TBAF as an activator, the formation of methyl, ethyl, n-propyl and n-butyl ethers with a range of aryl halides was achieved in good yield.
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Felipe-Blanco, Diego. "Salicylic Acid-Catalyzed Radical Arylations from In-situ Formed Arenediazonium Salts." Doctoral thesis, Universidad de Alicante, 2020. http://hdl.handle.net/10045/112757.
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In this thesis, it has been studied the deamination of aromatic amines, through in situ formed diazonium salts as reaction intermediates, catalyzed by salicylic acid, a nontoxic, eco-friendly and economic catalyst. In the early part of the thesis (Chapter I) it has studied the deamination process using THF as solvent as hydrogen donor and anilines as radical source, to carry the hydrodeamination reaction, as well as the process in its deuterodeamination manner using deuterated solvent. Following with this study in Chapter II and Chapter III, it has been studied the addition of the aromatic radicals, generated with the methodology employed in the first chapter, to different types of double bond, to form α-arylketones (Chapter II) and γ-aryl lactones, throw a following intramolecular cyclization (Chapter III). Finally, in Chapter IV was studied the construction of arylphosphonates, starting from anilines as radical source, and triphenylphosphite, and in this case specially, mechanism was hard explored. In every work, the methodologies could be scaled-up above 1 g, reaction mechanisms were proposed and studied through control and mechanistical experiments, and follow reactions were carried out.
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Svensson, Akusjärvi Emma [Verfasser]. "Mechanistic Investigations of the Direct Arylation of Pyridine N-oxides with Bromoarenes and Structure-Reactivity Relationship of Aryl Palladium Complexes in Transmetalations with Organoboron Compounds / Emma Svensson Akusjärvi." Berlin : Freie Universität Berlin, 2018. http://d-nb.info/1176635034/34.
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Bielawski, Marcin. "Efficient and High-Yielding Routes to Diaryliodonium Salts." Licentiate thesis, Stockholm : Department of Organic Chemistry, Stockholm University, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-7969.
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Findik, Hamide. "Potassium Permanganate/ Carboxylic Acid/ Organic Solvent: A Powerful Reagent For C-c Bond Formation, Aryl Coupling Reactions And Enone Oxidation Ipso-nitration Of Arylboronic Acids With Silver Nitrite/ Tmscl." Phd thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/12610472/index.pdf.
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The first part of the thesis presents the KMnO4/ carboxylic acid/ organic solvent which is a powerful reagent for C-C bond formation, aryl coupling reactions and enone oxidation. The a¢-acetoxylation of enones and the a-acetoxylation of aromatic ketones were carried out with potassium permanganate and acetic acid, in which acetoxylation products were obtained in 74-96% yields. The same reaction was carried out with carboxylic acids other than acetic acid, which furnished corresponding acyloxy ketones with the same regioselectivity. For the first time, formyloxylation products were synthesized in a 61-85% yield by using formic acid. The potassium permanganate and acetic acid method was also used for aryl coupling reactions. The reaction of arylboronic acids and aryl hydrazines in benzene with potassium permanganate and acetic acid in turn furnished biaryls in a 85-96% yield. We showed that potassium permanganate/carboxylic acid/organic solvent behaves as manganese(III) acetate. In the second part of the thesis, ipso-nitration of arylboronic acids with AgNO2/ TMSCl was performed. Nitration of aromatic compounds is one of the most extensively studied reactions, and nitroaryl moieties play key roles in the physical and chemical properties of many target molecules in organic synthesis. For electrophilic nitration of aromatic compounds, a wide variety of reagents are available to date. Most of them are very strong nitrating agents and often lead to further nitration and mixture of isomers. Since most nitrating agents are oxidants, oxidation of other functional groups can also occur, giving a mixture of products. Thus, a search for milder and selective nitrating agents is a good research goal. In this work, we aimed to apply AgNO2/ TMSCl system to ipso nitration of arylboronic acids.
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Monzón, Díaz Gabriel Andrés [Verfasser], and Paul [Akademischer Betreuer] Knochel. "Zincation of heterocycles and aryl nonaflates : directed magnesiation of highly substituted anilines and amino-substituted heterocycles ; synthesis of heterobenzylic zinc compounds ; new generation of iminium salts / Gabriel Andrés Monzón Díaz. Betreuer: Paul Knochel." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2012. http://d-nb.info/1025821947/34.
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Bielawski, Marcin. "Diaryliodonium Salts : Development of Synthetic Methodologies and α-Arylation of Enolates." Doctoral thesis, Stockholms universitet, Institutionen för organisk kemi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-54738.
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This thesis describes novel reaction protocols for the synthesis of diaryliodonium salts and also provides an insight to the mechanism of α-arylation of carbonyl compounds with diaryliodonium salts. The first chapter gives a general introduction to the field of hypervalent iodine chemistry, mainly focusing on recent developments and applications of diaryliodonium salts. Chapter two describes the synthesis of electron-rich to electron-poor diaryliodonium triflates, in moderate to excellent yields from a range of arenes and iodoarenes. In chapter three, it is described that molecular iodine can be used together with arenes in a direct one-pot, three-step synthesis of symmetric diaryliodonium triflates. A large scale synthesis of bis(4-tert-butylphenyl)iodonium triflate is also described, controlled and verified by an external research group, further demonstrating the reliability of this methodology. The fourth chapter describes the development of a sequential one-pot synthesis of diaryliodonium salts from aryl iodides and boronic acids, furnishing symmetric and unsymmetric, electron-rich to electron-poor diaryliodonium tetrafluoroborates in moderate to excellent yields. This method was developed to overcome the regiochemical limitations imposed by the reaction mechanism in the protocols described in the preceding chapters. Chapter five describes a one-pot synthesis of heteroaromatic iodonium salts under similar conditions described in chapter two. The final chapter describes the reaction of enolates with chiral diaryliodonium salts or together with a phase transfer catalyst yielding racemic products. DFT calculations were performed, which revealed a low lying energy transition state (TS) between intermediates, which is believed to be responsible for the lack of selectivity observed in the experimental work. It is also proposed that a [2,3] rearrangement is preferred over a [1,2] rearrangement in the α-arylation of carbonyl compounds. The synthetic methodology described in this thesis is the most generally applicable, efficient and high-yielding to date for the synthesis of diaryliodonium salts, making these reagents readily available for various applications in synthesis.
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Ranaivonjatovo, Henri Jacques. "Derives du phosphore et de l'arsenic dicoordonnes doublements lies : diphosphenes, diarsenes et phospha-arsenes." Toulouse 3, 1986. http://www.theses.fr/1986TOU30069.
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Synthese de diphosphenes, diarsenes et phospha-arsenes par la voie organolithiee (action de lithiens encombres sur les dichlorophosphines). L'action du dbu sur les trichlorogermyl phosphines rp(h)gecl::(3) s'est revelee une voie d'acces generale aux disphosphenes. Reactivite, structures
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Smith, S. J. "Novel alkyls, aryls and alkoxides of group 14 and 15 elements." Thesis, University of Sussex, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.373133.
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Cromer, Rémy. "Porphyrines n-substituees : modelisation de l'inhibition d'hemoproteines." Université Louis Pasteur (Strasbourg) (1971-2008), 1986. http://www.theses.fr/1986STR13015.
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Migration cobalt-azote des groupements : phenyl et styryl. L'etude des reactions de migration dans les porphyrines de cobalt(iii) aryliques a justifie l'utilisation de ces dernieres pour modeliser l'hydrazinolyse des hemoproteines. Les porphyrines de cobalt(iii) aryliques ont un comportement analogue a celui des porphyrines de fer(iii) aryliques. Oxydation des styryl -co(iii) porphyrines. Mecanisme de reaction. Extension de cette reaction a la cyclisation en serie arylique qui permet la synthese de la premiere porphyrine n,n'-(phenylene-1,2) analogue du produit d'inhibition suicide obtenu apres activation de l'amino-1 benzotriazole par divers enzymes a cytochrome p-450
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Figadère, Bruno. "Les composes organomanganeux mixtes : addition 1-2 selective sur des aldehydes ou des cetones portant un groupe fonctionnel, enolisation regioselective de cetones : application en synthese." Paris 6, 1987. http://www.theses.fr/1987PA066371.
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Les reactifs organomanganeux rmnx(x=cl, br, i; r=n-, sec- t-alkyl, alcenyl, aryl, alcynyl) s'additionnent aux aldehydes et cetones fonctionnels pour donner selectivement les alcools correspondant avec d'excellents rendements. Les reactifs rmnz(z=nphme) enolisent les cetones avec une excellente regioselectivite. Les enolates manganeux ainsi prepares sont tres aisement acyles, silyles, alkyles, hydroxyalkyles, avec des rendements de 60% a 90%, a la temperature ambiante
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Klopper, Reynhardt. "An investigation into the complex formation and potential solvent extraction of Os(IV/III) with N, N - dialkyl - N′- acyl(aroyl)thioureas." Thesis, Stellenbosch : University of Stellenbosch, 2006. http://hdl.handle.net/10019.1/2762.
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Thesis (MSc (Chemistry and Polymer Science))--University of Stellenbosch, 2006.This study involved the preliminary investigation into the potential liquid-liquid extraction of Os(IV/III) from hydrochloric acid solutions with ligands of type N,N-dialkyl-N′-acyl(aroyl)thioureas (HL), and ultimate selective pre-concentration and separation of Os(IV/III) from the other platinum group metals. Investigations have also been focused towards understanding the speciation of Os(IV) in hydrochloric acid medium. A series of osmium complexes with ligands of type HL have been synthesised and characterised. This has been done with a view towards understanding the interaction of Os(IV/III) with the HL ligands, and what the resultant stereochemical influences would be on the solvent extraction capabilities of the ligands. The structures of two novel osmium-containing compounds have been verified by means of X-ray crytallography. Firstly, the ion pair OsCl6[(C4H9)4N]2 was obtained as a result of liquid-liquid extraction experiments. Secondly, the only known example (in our knowledge) of an Os(III) - N,N-dialkyl-N′- aroylthiourea complex, in this case tris(N,N-diethyl-N’-benzoylthioureato)osmium(III), was successfully synthesised and characterised. Lastly, preliminary studies into the substitution reactions of ruthenium-polypyridine complexes with N,N-dialkyl-N′-acyl(aroyl)thioureas were conducted. A series of cis-bis(2,2′-bipyridine)(N,N-dialkyl-N′-acyl(aroyl)thioureato)ruthenium(II) complexes have been successfully synthesised and characterised. The electronic absorption behaviour of the formed complexes have been investigated in detail via UV-Vis spectrophotometry.
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Maddaluno, Jacques. "Synthèse énantiosélective de composés d'intérêt biologique : approche de polyols vicinaux par aldolisation stéréocontrôlée, approche de bêta-amino esters par addition de Michael stéréocontrôlée sous haute pression." Paris 6, 1986. http://www.theses.fr/1986PA066240.
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La réaction d'aldolisation des benzoylaryacetates avec l'acétaldéhyde fait ressortir la capacité de ce synthon à effectuer un transfert d'asymétrie. Etude de la réactivité des alcoxy-3 acroléines. L'addition d'amines primaire sur des crotonates à haute pression permettent d'obtenir de meilleures sélectivités
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Trabulsi, Houssam. "Préparation d’iminolactones par cyclisation électrophile d’hydroxamates insaturés : étude de leurs propriétés." Thesis, Paris 11, 2011. http://www.theses.fr/2011PA112052.
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Au cours de nos différents travaux sur les réactions de cyclisations électrophiles diastéréosélectives 5-endo d’hydroxamates insaturés par l’hexafluorophosphate de bromo biscollidine (HBB). Nous avons constaté la formation d’imidates cycliques et nous avons mis en évidence un réarrangement lactames-imidates. Une fragmentation de type Beckman aboutissant à la formation d’une famille de cyano énones, anisi qu’une nouvelle formation d’imidates a été étudiée.Dans l’introduction générale, nous avons rapporté différents exemples d’halolactonisations électrophiles 5-endo et 5-exo, énantio et diastériosélectives rapportés dans la littérature, ainsi que les facteurs influençant la régio et la diastereoselectivité de ces cyclisations.Dans le premier chapitre, après un rappel bibliographique sur les différentes synthèses de lactames à partir de différents substrats par cyclisation électrophile, nous avons présenté nos propres travaux.Le traitement d’hydroxamates β, γ−éthyléniques γ-disubstitués avec de l’hexafluorophosphate de bromo bis(sym-collidine) dans du dichlorométhane aboutit à la formation de lactames et d’imidates cycliques. On a pu confirmer par des études RMN, l’existence d’un réarrangement lactame-imidate cyclique.Dans une deuxième partie, nous avons étudié la diastereosélectivité de la cyclisation. A cet effet, des hydroxamates optiquement actifs ont été synthétisés via la méthodologie développée par Evans. Dans tous les cas, un seul produit, un bromo-imidate cyclique optiquement actif est obtenu.Dans le deuxième chapitre, l’étude de la réaction de cyclisation des hydroxamates β, γ−éthyléniques γ-monosubstitués avec HBB, nous a permis de mettre en évidence une fragmentation de type Beckmann. Cette dernière est améliorée par réaction des produits de cyclisation avec de la triethylamine. On a généralisé cette fragmentation en l’appliquant à différents substrats.Enfin, dans le troisième chapitre, après une étude bibliographique sur la synthèse d’imidates et leurs utilités en synthèse organique, on a synthétisé des imidates β, γéthyléniques, afin de les utiliser comme substrats dans la réaction de cyclisation éléctrophile utilisant HBB. Dans ce cas aussi, la formation d’imines cycliques est constatéeThis work deals with the 5-endo halogeno electrophilic cyclization reactions of β,γ-ethylenic hydroxamates to give halolactames and halo cyclic iminolactones.In the first chapter, the reaction of γ-disubstituted β,γ-unsaturated hydroxamates with bis(collidine)bromine(I) hexafluorophosphate is studied. This type of reaction led mainly to the formation of bromo cyclic imidates, which were the thermodynamic products. Unsaturated cyclic imidates were then obtained by reaction with triethylamine. A lactame-iminolactone rearrangement was obtained during those reactions. In a next step we decided to study the diastereoselectivity of the reaction, using optically actif hydroxamates. In the second chapter, we decided to study the reaction of bis(collidine)bromine(I) hexafluorophosphate with γ-aryl β,γ-unsaturated hydroxamates, the corresponding bromo cyclic imidates were also obtained. However, by reaction with triethylamine, these compounds led with good yields, to the formation of 3-cyano-2-propen-1-ones by a Beckmann type fragmentation reaction. In the third chapter, the reaction of γ-mono and disubstituted β,γ-unsaturated imidates with bis(collidine)bromine(I) hexafluorophosphate is studied. The results that we obtained were not sufficient enough to understand the electrophilic cyclization mechanism of these types of substrates
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Denis, Alexis. "Fonctionnalisations selectives a l'aide des complexes du palladium : synthese de composes d'interet biologiques, cyclopropanes vinyliques, aryl-3 oxazolidinones-2 (inhibiteurs potentiels de la monoamine oxydase)." Paris 6, 1987. http://www.theses.fr/1987PA066335.
Full textAbstract:
Ce travail porte sur l'utilisation du palladium (o) pour la synthese de molecules d'interet biologique. En premier lieu, on decrit la synthese stereoselective de cyclopropanes vinyliques et de pyrethrinoides. Dans un second temps, on etudie l'echange acetate phenol et l'amination de derives allyliques fibonctionnels. Enfin, on presente la synthese d'aryl-3 dihydroxy-5,5 oxazolidones-2 erythro et threo et etudie leur utilisation en tant qu'inhibiteur d'enzyme monoamine oxidase
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Denys, Goument Colombe. "Dicétones-1,4 thiosubstituées." Rouen, 1988. http://www.theses.fr/1988ROUES023.
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