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Dissertations / Theses on the topic 'Heterocyclic chemistry ; Heterocyclic compounds'

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Published: 4 June 2021
Last updated: 10 February 2022

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1

Hu, Gang. "Conducting polymers from heterocyclic compounds." Thesis, Open University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240331.

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2

Lewis, William. "Chiral Heterocyclic Ligands." Thesis, University of Canterbury. Chemistry, 2007. http://hdl.handle.net/10092/1383.

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This thesis describes the preparation and characterisation of a number of homochiral coordination and metallosupramolecular assemblies. These species were formed from the reaction of chiral pyridine and quinoline containing ligands and metal ions. The combination of traditional coordination chemistry and supramolecular interactions led to a range of polymeric and network structures being formed. The ligands used in this thesis can be divided into two broad categories: alkaloids and ligands derived from them, and amino acid-based ligands. In the first category three new ligands were synthesized, and a variety of routes towards alkaloid-based homochiral ligands were investigated. The second category focused on three ligand motifs, and resulted in the preparation of 16 ligands. These two categories of ligands were reacted with a range of metal salts to investigate their coordination and supramolecular chemistry. The structure of twenty complexes was determined by single crystal X-ray crystallography. The complexes had a range of structures, with discrete and polymeric species being formed. Hydrogen bonding was an important feature in the supramolecular chemistry of the complexes, playing a different role in different series of complexes. Two chiral coordination polymers and one chiral coordination network were synthesized. All three of these structures possessed directionality to some degree: in the coordination network and one of the polymers the directionality is counterbalanced by the opposite directionality being present in the crystal, while the second coordination polymer is generated by the screw axis present and has a high degree of overall directionality.
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3

Armugam, S. "Studies on N-Heterocyclic Compounds." Thesis, Indian Institute of Science, 1994. http://hdl.handle.net/2005/108.

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The thesis entitled "Studies on N-Hetero cyclic Compounds: (a) Reaction of 5,6,7,8-Tetrahydroisoquinolines with Vilsmeier Reagent and (b) Amide Induced in situ Alkylation of 5,6-Dihydroisoquinolines" is presented in two parts. Part I involves a study of the Vilsmeier reaction of 4-cyano-1,3-dihydroxy-5,6,7,8 tetrahydroisoquinoline derivatives, while Part II concerns the in situ alkylation of l-alkyl-4-cyano-3-methoxy-5,6- dihydroisoquinolines in presence of KNH2/liq.NH3.
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4

Wilson, Jennifer M. "Synthesis of biologically active heterocyclic compounds." Thesis, University of Glasgow, 2007. http://theses.gla.ac.uk/45/.

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More than 11 million people worldwide are diagnosed with cancer every year. New cancer drugs are required that are more effective and selective. Nitrogen mustard alkylating agents crosslink DNA inhibiting transcription and replication. Use of the mustard pharmacophore as part of a macrocycle allows metal complexation and produces a prodrug. Hypoxic tumour cells have increased concentrations of reductase enzymes which could lead to reduction of the complex in situ and release of a cytotoxic drug. Human African Trypanosomiasis is commonly known as Sleeping Sickness and affects over 36 countries of sub-Saharan Africa. It is transmitted to humans by the tsetse fly which carries the parasitic subspecies Trypanosoma brucei rhodesiense and Trypanosoma brucei gambiense. Any compounds synthesised would also be tested to assess their potential as anti-parasitic agents. Parker synthesised a range of polyazamacrocycles. Testing of compound A in vitro gave highly efficient DNA crosslinking activity. Copper complexes were formed of the macrocycles and B was found to be 24 times more toxic against hypoxic cells than oxic cells thus exploiting tumour hypoxia and creating a selective drug. Jones synthesised a range of oxaazamacrocycles such as C which when tested in vitro exhibited comparable cross-linking activity to the azamacrocycles although it proved impossible to synthesise the corresponding copper complexes. It was decided to vary the leaving group on the alkylating arms to see if the DNA crosslinking results could be improved. Eight carbamates and the corresponding copper complexes were synthesised. The R-groups were alkyl and aromatic. Anti-cancer DNA crosslinking and hypoxia selectivity results were disappointing however, a number of compounds displayed significant activity when tested against T. brucei. A range of thiaazamacrocycles would complete the set of heteroatom-containing macrocycles (N, O, S) and might produce good DNA crosslinking results. It might also be possible to synthesise the corresponding copper complexes producing prodrugs. Six thiaazamacrocycles were synthesised and 2-hydroxyethyl arms were attached. However it proved impossible to isolate the desired alkylating agents with the 2-chloroethyl arms. In the body, the p53 protein activates the transcription of specific genes. In healthy cells, the levels of p53 have to be kept to a minimum to allow the normal running of the cell, e.g. growth and replication. This function is carried out by the HDM2 protein, which forms an auto-regulatory feedback loop with p53. In some tumours, the p53 function is disrupted due to genetic mutations of p53. However other tumours possess ‘wild type’ p53 – this type of p53 has lost the ability to respond to oncogenic stress due to over-expression of HDM2. Drugs that inhibit HDM2 should cause stabilisation of p53 and induce apoptosis in cancer cells. A small library of 5-deazaflavins were synthesised and biologically tested producing some interesting biological results.
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5

Crockett, Rowena. "Generation of free radicals from heterocyclic compounds." Thesis, University of Aberdeen, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.290239.

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Tetrazolinones, thiatriazole 1-oxides and meso-ionic oxatriazoles were investigated as sources of free radicals. Mono-substituted tetrazolinones decomposed at their melting points. Nitrosation and nitration of the tetrazolinone ring was unsuccessful, although alkoxyalkylation of the ring took place in ether in the presence of nitrosomium and nitronium tetrafluoroborate. The tetrazolinone ring was photolytically unstable, and both eliminated nitrogen and cycloreverted. γ-irradiation of the naphthyl deivative caused cleavage of the nitrogen-hydrogen bond to give a radical which was identified by spin trapping and esr spectroscopy. Thiatriazolyl radicals were generated from thiatriazol-1-ium salts by reduction over sodium metal. Deuterium and nitrogen-15 labelled diphenylthiatriazolium salts were prepared in the reaction between thiatriazole 1-oxides and phosphorus pentachloride or pentabromide. This allowed an unambiguous assignment of the nitrogen and hydrogen hyperfine coupling constants in the esr spectrum of the unlabelled thiatriazolyl radical. X-ray crystallographic analysis was carried out on single crystals of 2,4-diphenyl-2,5-dihydro-1,2,3,5-thiatriazol 1-oxide and 2,4-diphenyl-2H-1,2,3,5-thiatriazol-1-ium bromide. Meso-ionic oxatriazolones were relatively stable to thermolysis, whereas oxatriazolimines decomposed at their melting points. The oxatriazolones decomposed on photolysis via two mechanistic pathways, while the oxatriazol-imines were resistant to photolysis. Radicals were generated by γ-irradiation and oxidation via decomposition of the heterocyclic ring. Electrochemical reduction of nitrophenyl derivatives allowed an investigation of radicals in which the heterocyclic ring was remote from the radical centre. Photochemical reaction between the nitrophenyl derivatives of the oxatriazole and tetrahydrofuran produced oxy-nitroxide radicals which were realatively long-lived and in which the heterocyclic ring was intact. The rates of hydrolysis and crystal structures of three diacetylazolinones, including diacetyltetrazolinone were investigated with the aim of determining whether a correlation existed between bond lengths and reactivity. The relative rates of hydrolysis were found to be independent of the bond lengths. However a correlation was found between the rates of hydrolysis and the acidity of the unsubstituted azolinones.
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6

Orton, Edward. "Synthesis and chemistry of 4,5-dimethylene-1,3-dioxolan-2-one and related compounds /." Thesis, Connect to this title online; UW restricted, 1985. http://hdl.handle.net/1773/8620.

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7

Speirs, Richard Allan. "New reagents and syntheses in heterocyclic organoselenium chemistry." Thesis, University of St Andrews, 1986. http://hdl.handle.net/10023/15417.

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The main aim of this project was to develop new reagents capable of exchanging selenium for oxygen under mild conditions, to obtain new carboselenaldehyde (1) and selone (2) compounds. Phenylphosphonoselenoic dichloride (3) was prepared as a solution in xylene. It was reacted with (1,2-dithiol-3-ylidene)carbaldehydes and indolizine-3-carbaldehydes to afford 1,6aλ4-dithia-6-selena-pentalenes (5) and indolizine-3-carboselenaldehydes (6), respectively. The indolizine-3-carbaldehydes had previously been prepared from the corresponding indolizines, in turn prepared from the appropriate pyridinium bromide salts. CHSe(5)(6)Phenylphosphonoselenoic dichloride (3) was also reacted with several other carbonyl compounds. Reactions with N,N.-dimethyl- fonnamide, 5-phenyl-3H-1,2-dithiol-3-one, 2,6-dimethyl-4H.-pyran-4-one, 4-hydroxypyridine, 1-methylpyrrolidin-2-one, hexeihydro-2H-azepin-2-one, and 2,4,6-cycloheptatrien-1-one met with varied success, and only N,N-dimethylselenoformamide (7), 5-phenyl-3H-1,2-dithiole-3-selone (8), and 2,6-dimethy1-4H-pyraxi-4-selone (9) were obtained.(8)(9)The presence of a stabilising substituent was therefore required, and was introduced as a tungsten pentacarboiyl species. Pentacarbon-yl(indolizine-3-carboselenaldehyde-Se) tungsten(0) (10) and penta-carbonyl(2,4,6-cycloheptatriene-1-selone-Se)tungsten(0) (11) were obtained from the reaction of the corresponding oarboryl compounds with phenylphosphonoselenoic dichloride (3) in the presence of tetra- ethylanunonium iodopentacarbonyltungstate(0).The reagent (4) was prepared from the reaction of chlorodlphenyl- phosphine and tetramethylammonium selenocyanate, and was reacted in situ with indolizine-3-carbaldehydes to produce not only indolizine-3-carboselenaldehydes (6), but also compounds which were proposed on the strength of spectral and analytical evidence as being members of the novel 3-(indolizin-3-yl)-2,5-dihydro-2-selenoformyl-1,2,4-selena- diazole-5-selone (12) system.
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8

Ganto, Mlungiseleli MacDonald. "Application of Baylis-Hillman methodology in the construction of complex heterocyclic targets." Thesis, Rhodes University, 2009. http://hdl.handle.net/10962/d1006703.

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Baylis-Hillman reactions using various aromatic aldehydes, activated alkenes and catalysts have been used to: - access an extensive range of poly-heterocyclic products;explore chemoselectivity; and optimise reaction efficiency. Chromone-3-carbaldehydes and chromone-2-carbaldehydes, prepared via Vielsmeier-Haack and Kostanecki-Robinson methodology, respectively, have been used as Baylis-Hillman substrates with four different catalysts, viz., 1,4-diazabicyclo[2.2.2]octane (DABCO), 3-hydroxyquinuclidine (3-HQ), imidazole and N’,N’,N’,N’- tetramethylpropanediamine (TMPDA), and with methyl vinyl ketone (MVK), methyl acrylate, cyclic enones (2-cyclohexen-1-one, 2-cyclopenten-1-one and chromones) as activated alkenes. Reactions of the chromone- -carbaldehydes with MVK afforded dimeric Baylis-Hillman adducts when catalyzed by DABCO but when the same reactions were repeated using 3-HQ as catalyst, the dimeric products were accompanied by tricyclic Baylis-Hillman adducts. Use of excess MVK, however, led to mixtures of the normal Baylis-Hillman adducts and the tricyclic adducts – interestingly, with the apparent absence of the dimeric products. While reactions of chromone-3-carbaldehydes with methyl acrylate afforded the normal Baylis-Hillman adducts, the chromone-2- carbaldehydes produced, instead, rearrangement products, consistent with an earlier, single observation. Reactions of 2-nitrobenzaldehydes with cyclic enones using imidazole as catalyst afforded the normal Baylis-Hillman adducts, reductive cyclisation of the 2-cyclohexen-1- one and 2-cyclopenten-1-one adducts, using acetic acid and iron powder, afforded the corresponding quinoline erivatives. Treatment of cyclic enones with pyridine-2-carbaldehydes and quinoline-2-carbaldehydes using TMPDA as catalyst generally gave the expected Baylis-Hillman adducts. However, indolizine derivatives were isolated directly from Baylis-Hillman reactions involving pyridine-2-carbaldehydes and 2-cyclohexen-1-one. The remaining Baylis-Hillman adducts were cyclized to the corresponding indolizines by treatment with acetic anhydride both under reflux and under microwave-assisted conditions, the latter approach providing remarkably rapid and efficient access to the polycyclic products. Computer modelling studies have been conducted on selected polycyclic products at the Molecular Mechanics (MM), Quantum Mechanical (QM) and Density Functional (DFT) levels. The theoretical results have been used to calculate UV, IR and NMR absorption data, which have been compared, in turn, with the experimental spectroscopic data. Use has also been made of the estreNova NMR prediction programme and, generally, good agreement has been observed between the predicted and experimental spectroscopic data.
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9

Nocanda, Xolani Wittleton. "Applications of Baylis-Idllman methodology in the synthesis of chromene derivatives." Thesis, Rhodes University, 2001. http://hdl.handle.net/10962/d1018257.

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The reaction of salicylaldehyde with various activated alkenes, viz., methyl vinyl ketone, ethyl vinyl ketone, phenyl vinyl sulfone, phenyl vinylsulfonate, acrolein and acrylonitrile, under Baylis-Hillman conditions, has been found to proceed with the chemoselective formation of chromene derivatives. The reaction conditions have been optimised and chromene derivatives have been obtained in isolated yields up to 87 %. The generality of the reaction, using 1,4-diazabicyclo[2.2.2]octane (DABCO), as the catalyst, and a heterogeneous (chloroform-water) solvent system, has been established using a range of salicylaldehyde derivatives,. including 2-hydroxynaphthaldehyde. The formation of chromene derivatives, under these conditions, has been assumed to proceed via an initial, Baylis-Hillman reaction, followed by cyclisation involving intramolecular conjugate addition, and subsequent dehydration. Evidence supporting this sequence has been obtained from the isolation ofBaylis-Hillman products from reactions involving the use of tertbutylclimethylsilyl-protected salicylaldehyde, 4-hydroxybenzaldehyde and tert-butyl acrylate as substrates. The potential of the ''Baylis-Hillman zwitterion" to participate as a donor species in Michael-type addition reactions has been explored and a series of climeric products has been isolated. The Baylis-Hillman methodology has also been successfully extended to the synthesis of sulfurcontaining heterocyclic systems, and a range of 3-substituted thiochromenes has been obtained in moderate yields, using 2,2'-dithiobenzaldehyde and various activated alkenes in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) as catalyst. The electron-impact mass spectra of selected chromene and thiocbromene derivatives have been investigated permitting comparison of the fragmentation of the oxygen- and sulfur-containing analogues. In a study directed at the synthesis of potential HIV -1 protease inhibitors, chromene- and thiocbromene-containing analogues of the clinically useful drug, ritonavir, have been prepared. Thiochromene and chromene derivatives were converted to the corresponding 3 -carboxylic acids and coupled with a specially prepared, hydroxyethylene dipeptide isostere to afford ritonavir analogues containing cbromene and thiochromene termini in ca. 60% yield.
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10

Ho, Yee-Ping. "Some studies in nitrogen heterocyclic chemistry using Reissert compounds." Thesis, Loughborough University, 1986. https://dspace.lboro.ac.uk/2134/33250.

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The thesis reports the first examples of Reissert compounds prepared from five-membered ring heterocycles. The method utilises trimethylsilyl cyanide as the key reagent in a single phase non-aqueous medium. Previous attempts to synthesise such compounds have failed because, under the conventional two phase conditions, the reaction either does not proceed or ring opening of the heterocycle occurs. Reaction of benzothiazole with an acid chloride (aliphatic, aromatic or chloroformate) and trimethylsilyl cyanide in dichloromethane has been shown to give rise to 3-acyl-2-cyano-2,3-dihydrobenzothiazoles. Eight such five-membered ring Reissert compounds have been prepared, mostly in yields exceeding 70%. The mechanistic involvement of trimethylsilyl cyanide is discussed. The novel Reissert compounds have been shown to be versatile intermediates for the further modification of the starting heterocycles.
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11

Lee, On-yi. "Synthesis of heterocycles via phenylseleno group transfer radical cyclization and chemoselective reductive amination promoted by InCl3." Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/HKUTO/record/B3955756X.

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12

Stewart, Lesley Ann. "Synthesis of heterocyclic compounds as potential anticancer agents." Thesis, University of Glasgow, 1996. http://theses.gla.ac.uk/4936/.

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13

Fallah, Asadollah. "Stereochemistry and reactivity of some 1,3-heterocyclic compounds." Thesis, University of Portsmouth, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328185.

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14

Khan, Musharraf Naveed. "Synthesis of different heterocyclic compounds of pharmaceutical relevance." Thesis, University of Huddersfield, 2013. http://eprints.hud.ac.uk/id/eprint/19503/.

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This thesis describes the synthesis of different cyclic imines and the exploration of their reactivity with cyclopropenones and 1,3-dipoles,as well as an investigation of the chemistry of the products. The synthesis of biologically and pharmaceutically important heterocyclic natural product analogues, such as the pyrroloazepines, indolizidines and pyrrolizidines has been achieved using a cycloaddition reaction between cyclic imidates and cyclopropenones. A new route to pyridines has been developed using the generation of a proposed 3-azacyclopentadienone as the key step. The 3-azacyclopentadienones are generated by using boiling toluene to induce a [2+2]-cycloreversion in a series of azabicyclo[3.2.0]hept-2-en-4- ones. Regiospecific Diels-Alder reaction of the intermediate 3-azacyclopentadienone with a styrene is followed by chelotropic extrusion of carbon monoxide and loss of hydrogen to give the pyridine. The process is similar to the well-known process by which benzenes are accessed from cyclopentadienones. The azabicyclo[3.2.0]hept-2 en-4-ones were available from the reaction of cyclopropenones with 1-azetines, where cyclopropenones behave as an all carbon 1,3- dipole equivalents. Using the same methodology 1,3-dipolar cycloaddition of nitrile oxides to 4-aryl-2-alkylthio-1-azetines afforded a series of oxadiazabicyclo[3.2.0]heptenes as single diastereoisomers. Heating these cycloadducts in toluene resulted in an overall [2+2]- cycloreversion to give 5-alkylthio-3-aryl-1,2,4 oxadiazoles. Cycloaddition reactions of a series of benzodiazepines were also studied. The benzodiazepines were formed using literature methods and converted to cyclic imines with the help of Meerwein’s reagent. Reactions between such cyclic imines and cyclopropenones and 1,3 dipoles were attempted to produce tricyclic and tetracyclic benzodiazepine analogues. Finally, some multicomponent reactions of aryl aldehydes with cyanides and 1,3-dicarbonyl compounds were investigated to produce fully substituted heterocyclic compounds like dihydropyridines and pyrans with substituents suitable for intramolecular cyclization and imine formation. The main substituent of interest was the azide group as this had been used in section 2.3.3.1.2 & 2.3.3.1.3 in this thesis.
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15

Lapinsky, David J. "STUDIES IN AZIRIDINE-ALLYLSILANE CHEMISTRY: EXTENSION OF SCOPE." Columbus, OH : Ohio State University, 2002. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1038954949.

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Thesis (Ph. D.)--Ohio State University, 2003.
Title from first page of PDF file. Document formatted into pages; contains xx, 256 p.: ill. (some col.). Includes abstract and vita. Advisor: Stephen C. Bergmeier, College of Pharmacy. Includes bibliographical references (p. 234-256).
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16

Black, Helen Dinah. "Kinetics of hydroxyl radical reactions with heterocyclic compounds." Thesis, University of Leeds, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.305373.

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17

Robinson, William J. III. "Development of Tetrathiafulvalene Fused N-Heterocyclic Carbene Compounds." Wright State University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=wright1610382201476554.

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18

Hales, Ivan Daniel Cashman. "Flash vacuum pyrolysis of selected heterocyclic and unsaturated compounds." Thesis, London Metropolitan University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.321720.

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19

Yusoff, M. I. "The acid-catalysed hydrolysis of some mesoionic heterocyclic compounds." Thesis, University of Essex, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234173.

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20

Hunter, Gordon A. "Synthesis and properties of 3-hydroxypyrroles, 3-hydroxythiophenes, and related compounds." Thesis, University of Edinburgh, 1990. http://hdl.handle.net/1842/15064.

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21

Grisle, Roger Anthony. "Synthesis of novel heterocyclic difluoro monomers via the chemistry of reissert compounds." Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-05042010-020216/.

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22

Roberto, Dominique Marie. "Metal-catalyzed reactions of heterocyclic nitrogen compounds and related systems." Thesis, University of Ottawa (Canada), 1989. http://hdl.handle.net/10393/5773.

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23

Guilani, Bardia. "Synthesis of novel heterocyclic polymers via the chemistry of Reissert compounds." Thesis, Virginia Tech, 1990. http://hdl.handle.net/10919/42072.

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The chemistry of a well established class of compounds, known as Reissert compounds, was used to prepare several novel N-heterocyclic polymers. Initially, alkylation of quinoline Reissert compounds was closely examined to test the feasibility of the use of such compounds as difunctional monomers. An A-B and an A-A monomer were then prepared by the reaction of quinoline with p-formylbenzoyl chloride and isophthaloyl chloride, respectively. The former monomer could be polymerized interfacially to afford a low molecular weight polyester exhibiting Tg of 190°C.

Several novel bis-isoquinolines were prepared using an en amine reaction reported by Minter and Re.52 One of these bis-isoquinolines was used to prepare two novel bis-Reissert compounds which could be polymerized with several dialdehydes to obtain high molecular weight N-heterocyclic polyesters. Cleavage of the ester groups afforded a novel N-heterocyclic polyalcohol. It was observed that circumvention of a rearrangement reaction particular to Reissert compounds by molecular design led to the synthesis of N-heterocyclic polyesters that had the highest molecular weights and intrinsic viscosities.

A novel N-heterocyclic difluorodiketone was prepared in four steps using the enamine reaction of Minter and Re52 and Reissert compound chemistry. The diketone was polymerized via standard techniques 72 to afford several novel poly(N-heteroaryl-ether-ketones) with high glass transition temperatures and thermal stabilities. Thus, polymerization of 1,4-bis(4-fluorobenzoyl)isoquinoline with biphenol yielded a poly(ether-ketone) with an intrinsic viscosity of 0.34 dl/g. This polymer showed Tg at 209°C and was stable up to 500°C in air.


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24

Portela-Cubillo, Fernando. "Oxime derivatives : versatile reagents for radical-mediated syntheses of heterocycles." Thesis, St Andrews, 2009. http://hdl.handle.net/10023/856.

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25

Berlin, Stefan. "Construction of Five-Membered Heterocyclic Compounds via Radical Cyclization." Doctoral thesis, Uppsala University, Department of Chemistry, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-3429.

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This thesis describes how radical cyclization chemistry can be applied for the construction of heterocyclic compounds.

In the first part, a series of electron deficient α-phenylselenenylalkenes were prepared via a PhSeCl-addition/HCl-elimination sequence. Allyl- and propargylamines readily underwent conjugate addition to these species to produce pyrrolidines or dihydropyrrol derivatives, after triethylborane initiated reductive radical cyclization in the presence of tris(trimethylsilyl)silane.

The second part describes a convergent synthesis of the pineal hormone melatonin. The indole nucleus is secured via a tris(trimethylsilyl)silane mediated 5-exo radical cyclization. The protocol provides convenient and simple access to compounds useful for studies of biological activity and structure activity relationships.

The third part describes construction of substituted tetrahydrofuran-3-ones and pyrrolidin-3-ones. Regioselective ring-opening of epoxides or aziridines with benzeneselenolate/tellurolate, followed by Michael addition to electron deficient alkynes afforded the corresponding O/N-vinylated compounds. The tetrahydrofuran-3-ones and pyrrolidin-3-ones were secured via radical carbonylation/reductive cyclization using pressurized carbon monoxide (80 atm).

The fourth part is concerned with the effect of an N-protecting group on the cyclization of 2-substituted-3-aza-5-hexenyl radicals. Relative energies for reactants and transition states were determined using density functional calculations. Reactant and transition state conformers leading to cis-product were lower in energy than those leading to trans-product. The results can be explained by the unfavorable 1,2-strain present in chair-equatorial and boat-equatorial conformers.

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26

Yuen, Yue Tai. "Trithiazyl trichloride in the synthesis of sulfur-nitrogen heterocyclic compounds." Thesis, Imperial College London, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.362732.

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27

Roxburgh, C. J. "The synthesis of heterocyclic compounds from Indan-1, 3-diones." Thesis, University of Portsmouth, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234430.

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ABSTRACT 2-Phenyl-indan-1,3-dione reacts via a Michael addition with 2-vinylpyridine to yield 2-phenyl-2-(2-(2-pyridyl) ethyl) indan- 1,3-dione, which on catalytic hydrogenation of the pyridine ring yields, via a ring cyclization/expansion reaction, rel(12S,14aR) 12- phenyl-1~3,4,12,13,14,l4a-octahydropyrido[l,2-£] [2]benzazonin- 6,ll-dione. A lithium aluminium hydride reduction of rel(12S,14aR) 12- phenyl-l,2,3,4,12,l3,14,14a-octahydropyrido[l,2-£] [2]benzazonin- 6,ll-dione yielded rel(llS,12S,l4aR) ll-hydroxy l2-phenyl-substituted derivative as the only isomer~ Various derivatives of this system including the 12-phenyl-ll-keto compound were synthesised and the stereochemistry of these established in each case. Treatment of rel(11S,12S,14aR)12-phenyl-l,2,3,4,6,11,12,13,14,14a-decahydropyridoTl, 2~b] [2]benzazonin-l1-ol with tosylchloride yielded the spiro quaternary nitrogen compound rel(4aR,7S,7aR,13S) 1,2,3,4,4a,S, 6,7,7a,12-decahydro-7-phenylisoindolo[l~2-~]quinoliZin-13-ium tosylate via transannular displacement of the I1-tosyl group. Treatment of this with lithium aluminium hydride uncovered a novel ring expansion to rel(SS,6R,10R,13S)5,6,7,8,9,10,11,12,13,14- decahydro-13-phenyl-S,6~10~nitrilobenzocyclododecene. Treatment of rel(11~,12~,14aR) 12-phenyl-l,2,3,4,6,11,12,13,- 14,14a-decahydropyrido[l,2-b) [2)benzazonin-l1-ol with phosphorus oxychloride in pyridine yielded two compounds, rel(4aR,7S,7aR,13S) 1,2,3,4,4a,S,6,7,7a,12-decahydro-7-phenylisoindolo[1,2-d]quinolizin- 13-ium phosphate via a transannular reaction and rel(11K,12R,14aR)- 12-phenyl-l,2,3,4,6,11,12,13,14,l4a-decahydropyrido[1, 2-Q) [2]benzazonin- ll-ol with a change in piperidine/benzazonine ring fusion stereochemistry. 2-Phenyl-2-(2-(1,2,3,4-tetrahydroquinolin-2-yl)ethyl)indanl, 3-dione did not undergo the ring closure/expansion sequence and attempts to prepare 2-phenyl-2-(2-(S-ethyl-2-piperidyl)ethyl)indanl, 3-dione and 2-methyl-2-(2-(2-piperidyl) ethyl) indan-l,3-dione to investigate a similar reaction were thwarted by non-selective reduction. Hydrazinolysis of 2-phenyl-2-(3-~-phthalimido)indan-l,3-dione gave 1,2,3,4-tetrahydro-l0b-hydroxy-l-phenylpyrido[2,1-~)isoindol- 6(4li)-one as the major product. A lithium aluminium hydride reduction of this gave rel(lR,lObR) I-phenylbenzo[a]isoindole. 2-p-Methoxyphenyl-2-(2-(2-piperidyl)ethyl)indan-l,3-dione did not undergo the ring cyclization/expansion reaction to a ninemembered ring but 2-p-chlorophenyl-2-(2-(2-piperidyl)ethyl)indan- 1,3-dione gave rel(12~,14aR)12-p-chlorophenyl-l,2,3,4,l2,l3,14,14aoctahydropyrido[ 1,2-Q) [2]benzazonine-6,11-dione. Lithium aluminium hydride reduction of this gave rel(ll~,12~,14aB) and rel(llR,l2~,- 14aR) 12-p-chlorophenyl-l,2,3,4,6,ll,l2,13,l4,l4a-decahydropyrido[ l,2-QJ (2)benzazonin-ll-ol in equal amounts. A variety of analogues of the above systems were prepared to test the generality of the ring closure/expansion sequence. None of these gave the required products showing the necessity of the basic 2-phenyl-indan-l,3-dione unit for successful reaction
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28

Worakun, Tanachat. "Palladium and rhodium catalysed construction of carbocyclic and heterocyclic compounds." Thesis, Queen's University Belfast, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317069.

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29

Somphol, Kittiya Chemistry Faculty of Science UNSW. "Synthesis of new heterocyclic structures based on indoles." Awarded by:University of New South Wales. Chemistry, 2007. http://handle.unsw.edu.au/1959.4/40829.

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Novel indolo-macrocycles have been generated from the attempts to synthesise bis-indolo-cyclotriveratrylenes by the condensation of I, I'-diindolyl-3,3'-dimethanols catalysed by p-toluenesulfonic acid. The addition of substituents on indoles led to enhanced solubilities of the macrocycles. Nine- and six-membered ring compounds have been synthesized from the acid-catalysed reaction of I,I'-diindolyl compounds and aryl aldehydes. Some reactions of these compounds and the attempted synthesis of 2,2' diindolylmethanes from the cyclic compounds have also been described. The electrophilic substitution reactions of 3-substituted 4,6-dimethoxyindole 2,6-dimethanols and 3-substituted 4,6-dimethoxyindole-7 and 2-carbaldehydes and I-substituted indoles afforded triindolyl dialdehydes. The wriation of substituents at C-7 of indole-7-aldehydes and at C-2 of indole-2-aldehydes has also been discussed. Reaction of the hydroxymethylindole and 1,2-di(indol-I-ylmethyl)benzene gave a new macrocycle. Substitution reactions of 2,2???-diindolylmethane-7,7'-dimethanol and indole-7- and 2-aldehydes gave tetraindolyl dialdehydes. Sodium borohydride reduction of tri- and tetra-indolyl dialdehydes gave tri- and tetra-indolyl dimethanols respectively. Acid-catalysed reactions of tri- and tetra-indolyl dimethanols afforded only calix[3] and [4]indoles respectively when all substituents at C-3 of indoles were aryl groups. New conditions for indole based imine synthesis have been established Macrocyclic imine formation from mono-, di-, tri and tetra-indolyl dialdehydes has been investigated. Reactions of indole-3, 7-dialdehydes and short chain diamines (1,2-diaminoethane, 1,2-diaminobenzene and 1,6-diaminohexane) gave mixtures while the reactions with long chain diamines (1,10 diaminodecane and 1,12-diaminododecane) gave monoindolyl macrocyclic imines. Reaction of indole-2, 7-dialdehydes and short chain diamines afforded diindolyl macrocyclic imines with head-tail structures, and the 2,7';2',2";7",2'''-Tetraindole-7 ,7"'-dialdehyde underwent cyclisation with triindolyl dialdehydes and 1,6-diaminohexane afforded triindolyl macrocyclic imines. 1,2 diaminoethane while the 2,3 ';1',1 ";3 ",2"'-tetraindole-7,7"'-dialdehydes underwent imine, with its precise structure established by X-ray crystallography. Reaction of of 1,3-di(indol-l-ylmethyl)benzene and 1,2 diaminoethane yielded a new macrocyclic reactions with long chain diamines yielded monoindolyl macrocyclic imines. Reaction ring closure with 1,2 diaminoethane and 1,6-diaminohexane.
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30

李安怡 and On-yi Lee. "Synthesis of heterocycles via phenylseleno group transfer radical cyclization and chemoselective reductive amination promoted by InCl3." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B3955756X.

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31

Burnett, Duane Arthur. "Synthesis of nitrogen containing heterocycles /." The Ohio State University, 1986. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487264603219377.

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32

陳淑妤 and Suk-yu Florence Chan. "Novel synthesis and chemistry of 1, 4, 2-dithiazolium salts." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1988. http://hub.hku.hk/bib/B30426352.

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33

Le, Gourrierec Denis. "Excited state intramolecular proton transfer (ESIPT) to nitrogen in heterocyclic compounds." Thesis, University of Central Lancashire, 1996. http://clok.uclan.ac.uk/21906/.

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Excited state intramolecular proton transfer (ESIPT) reactions have aroused considerable interest in the last 10-15 years. The ESIPT reaction is normally extremely rapid and yields excited species of considerably lower energy than the initial Franck-Condon excited state. ESIPT has therefore been used for the rapid dissipation of energy (e. g. for polymer protection against UV degradation) and to produce fluorophores with large Stokes shifts. Approximately half of the compounds studied to date involve ESIPT to nitrogen but there has been no real attempt at a coherent study of ESIPT to nitrogen. In this work we have tried to remedy this deficiency by studying a range of compounds of increasing complexity in order to characterise ESIPT and subsequent reactions and to evaluate how these properties vary with molecular structure. The molecules selected for this studyf all into two categories: - The azole group includes the 2-(2'-hydroxyphenyl)-oxazole (HPO) and -thiazole (HPT) whose study complements their well known benzo counterparts (HPBT and HPBO) and the related imidazoles. - The compounds of the pyridine group are related to the basic structure of 2-(2'-hydroxyphenyl)-pyridine (HPP). Structural variations involve benzo fusion (quinolines) and addition of a 3,3' bridge. A complementary compound is the well studied 2,2'-bipyridyl-3,3'-diol (BP(OH)2) which undergoes double proton transfer. Whenever possible, the methoxy counterparts were prepared in order to study the photochemistry of these compounds when ESIPT is not possible. The absorption and fluorescence properties of these systems were studied as a function of solvent, temperature and pH conditions. Lifetimes, quantum yields and pKa data were determined under these various conditions and semi-empirical quantum chemical calculations were performed on each system.
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34

Creeke, Paul Ivan. "Electrophilic additions to functionalised alkenes : the chemistry and synthesis of heterocyclic compounds." Thesis, University of Southampton, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.255650.

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35

Chowdhury, M. L. A. "Oxidation of peptides : synthesis of heterocyclic compounds related to the penicillins." Thesis, Oxford Brookes University, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.370498.

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36

Sokmen, Munevver. "Studies of the metal ion-catalysed oxidation of heterocyclic sulfur compounds." Thesis, Sheffield Hallam University, 1997. http://shura.shu.ac.uk/20384/.

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Chemical oxidation by hydrogen peroxide is used for the treatment of hazardous organic materials present at low concentrations in contaminated soil and water. A knowledge of the oxidation of thiophene and its derivatives, with particular reference to oxidative destruction and the identification of intermediate oxidation products would be useful for a deeper understanding of reaction mechanisms in waste treatment and the optimization of conditions. In this thesis, the oxidation of thiophenes, namely thiophene and 2- and 3-methylthiophene, with hydrogen peroxide and catalyst systems, e.g. Fenton's reagent, Gif systems and titanium dioxide-assisted photocatalytic oxidations, all of which may involve the formation of free radicals, e.g. the hydroxyl radical (HO-), has been studied. Fenton-related catalyst systems, mixtures of iron salts (and sometimes also with copper salts) and hydrogen peroxide, have been suggested in the literature and their reactions with thiophenes have been investigated. Additionally, other catalytic systems that have also been suggested in the literature as having potential have been studied. The oxidation of thiophene derivatives with Fenton-like reagents involving a combinations of hydrogen peroxide with other metal salts including vanadium(IV), titanium(III), copper(I) and copper(II) have been explored, since all of these systems appear to form hydroxyl radicals. Further Fenton-related oxidations of reaction intermediates have been carried out in order to help understand whether the oxidation products described are derived directly from the original compound or from further oxidation of a reaction intermediate. The progress of the oxidation reactions was followed by chromatographic analysis, using Gas Chromatography-Mass Spectrometry and High Performance Liquid Chromatography, so as to establish the nature of the oxidation products and the possible reaction pathways. Components of the mixtures were identified by comparison with commercially available products or synthetic standards. Oxidation reactions were monitored over set time intervals and the amounts of residual thiophenes were determined. In all of the oxidation reactions investigated, Fenton-related and Fenton-like, heteroaromatic ring destruction was observed, together with the formation of small amounts of hydroxylated ring products and dimeric structures. The oxidative destruction of thiophenes was successfully achieved with the above catalyst systems in the presence of excess hydrogen peroxide. Recent literature has questioned the formation of hydroxyl radicals in Fenton-related systems, and in order to contribute to the debate regarding the oxidizing species responsible for the destruction of each of the thiophenes, the oxidation reactions have been carried out in the presence of a complexing agent such as ethylenediaminetetraacetic acid (EDTA), and a radical trapping reagent 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO), respectively. Evidence of radical trapping was observed. Gif chemistry may involve the formation of high oxidation state iron complexes rather than free radicals. The oxidation of thiophenes was carried out using Fenton's reagent under Gif conditions and the results were compared with those from conventional Fenton and related conditions, to determine whether free radical species are involved in the latter. Radical derived products were again observed. Titanium-catalysed photooxidation has also formed part of this study to determine the nature of intermediate products which might be similar to those from Fenton-catalysed systems. For these reasons, the photocatalytic oxidation of 2-methylthiophene was studied in aqueous solution and the reaction was conducted in the presence and absence of titanium dioxide under an oxygen atmosphere. A similar range of radical derived products was found as in the conventional Fenton and related systems.
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37

Palucki, Brenda Lynn. "Synthesis of heterocyclic compounds via intramolecular [4+2] cycloadditions of conjugated enynes." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/42655.

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38

Chuckowree, Irina S. "Heterocyclic compounds for the treatment of cancer : a mechanistic rationale." Thesis, University of Greenwich, 2010. http://gala.gre.ac.uk/8097/.

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39

Quezada, Carol A. "N-Heterocyclic Carbenes: From Heterocyclynes to Potential Radiopharmaceuticals." Akron, OH : University of Akron, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=akron1116249871.

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40

Lombard, M. J. "Aspects of the use of N-O heterocyclic compounds in organic synthesis." Thesis, University of Oxford, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.370281.

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41

Chen, Ziqiu. "High resolution microwave and infrared spectroscopy of four-membered heterocyclic compounds." Elsevier, 2009. http://hdl.handle.net/1993/22078.

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High resolution molecular spectroscopic techniques are useful tools to accurately probe energy differences between quantum states of molecules. These energy levels are inherently dependent on the underlying potential functions, which ultimately govern the structures and dynamics of molecules. Thus, the detailed characterization of potential energy profiles through molecular spectroscopy provides important information about molecular properties. Given the increased structural and dynamic complexity of large molecules, small compounds serve as excellent prototypes to establish quantum mechanical models that accurately characterize quantum states and ultimately potential energy functions of various molecular classes. This thesis describes the use of rotational and rovibrational spectroscopy to probe one such class: four-membered heterocycles. Rotationally-resolved vibrational spectra of four-membered rings including β-propiolactone (c-C3H4O2), 3-oxetanone (c-C3H4O2), azetidine (c-C3H6N) and silacyclobutane (c-C3H8Si) were recorded below 1200 cm-1 using a Fourier transform infrared spectrometer (FTIR) with synchrotron light at the far infrared beamline of the Canadian Light Source (CLS). Additionally, Fourier transform microwave (FTMW) spectroscopy was used to study the pure rotational spectra of β-propiolactone and silacyclobutane for the first time. This allowed the accurate characterization of the ground vibrational state and molecular structure in support of the rovibrational analysis. The far infrared vibrational modes of these four molecules were analyzed individually initially and followed by a global fit of all observed transitions of each molecule. Unique spectroscopic signatures arising from Coriolis coupling(β-propiolactone, 3-oxetanone), tunneling motions (azetidine, silacyclobutane) and the large amplitude ring puckering vibration (3-oxetanone, azetidine, silacyclobutane) were revealed and treated. The resultant Hamiltonian models used for each molecule account for the observed spectra as the spectroscopic constants are consistent across the ground state and all vibrationally excited states studied. Collectively, these studies have provided a highly effective working protocol for the treatment of high resolution rovibrational data to model the dynamic behaviour of real molecules.
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42

姚大源 and Tai-yuen Yue. "Cycloaddition reactions of 2-vinylchromones." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1992. http://hub.hku.hk/bib/B31210661.

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43

Mampa, Richard Mokome. "X-ray and NMR spectropscopic studies of selected heterocyclic compounds of phosphorus and nitrogen /." Pretoria : [s.n.], 2000. http://upetd.up.ac.za/thesis/available/etd-02092006-155713/.

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44

Abedelrasoul, Abuelgasim Abbaker. "Studies on the chemistry of some sulphides and of some sulphur-containing heterocyclic compounds." Thesis, University of Hull, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.333763.

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45

Schwedtmann, Kai, Robin Schoemaker, Felix Hennersdorf, Antonio Bauzá, Antonio Frontera, Robert Weiss, and Jan J. Weigand. "Cationic 5-phosphonio-substituted N-heterocyclic carbenes." Royal Society of Chemistry, 2016. https://tud.qucosa.de/id/qucosa%3A30233.

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2-Phosphanyl-substituted imidazolium salts 2-PR2(4,5-Cl-Im)[OTf] (9a,b[OTf]) (4,5-Cl-Im = 4,5-dichloro-1,3-bis(2,6-di-isopropylphenyl)-imidazolium) (a: R = Cy, b: R = Ph) are prepared from the reaction of R2PCl (R = Cy, Ph) with NHC 8 (4,5-dichloro-1,3-bis(2,6-di-isopropylphenyl)-imidazolin-2-ylidene) in the presence of Me3SiOTf. 5-Phospanyl-substituted imidazolium salts 5-PR2(2,4-Cl-Im)[OTf] (10a,b[OTf]) are obtained in quantitative yield when a slight excess of the NHC 8 is used. 5-Phosphonio-substituted imidazolium salts 5-PR2Me(2,4-Cl-Im)[OTf]2 (14a,b[OTf]2) and 5-PR2F(2,4-Cl-Im)[OTf]2 (16a,b[OTf]2) result from methylation reaction or oxidation of 10a,b[OTf] with XeF2 and subsequent fluoride abstraction. According to our quantum chemical studies the Cl1 atom at the 2-position at the imidazolium ring of dication 14b2+ carries a slightly positive charge and is therefore accessible for nucleophilic attack. Accordingly, the reaction of 14a,b[OTf]2 and 16a,b[OTf]2 with R3P (R = Cy, Ph) affords cationic 5-phosphonio-substituted NHCs 5-PR2Me(4-Cl-NHC)[OTf] (17a,b[OTf]) and 5-PR2F(4-Cl-NHC)[OTf] (18a,b[OTf]) via a SN2(Cl)-type reaction. A series of transition metal complexes such as [AuCl(5-PPh2Me(4-Cl-NHC))][OTf] (19[OTf]), [CuBr(5-PPh2Me(4-Cl-NHC))][OTf] (20[OTf]), [AuCl(5-PPh2F(4-Cl-NHC))[OTf] (21[OTf]) and [RhCl(cod)(5-PPh2Me(4-Cl-NHC))][OTf] (23[OTf]) are prepared to prove the coordination abilities of carbenes 17b[OTf] and 18b[OTf]. The isolation of a rare example of a tricationic bis-carbene silver complex [Ag(5-PPh2Me(4-Cl-NHC))2][OTf]3 (22[OTf]3) is achieved by reacting 14b[OTf] with Cy3P in the presence of AgOTf. NHC 17b[OTf] represents a very effective dehydrocoupling reagent for secondary (R2PH, R = Ph, Cy, iBu) and primary (RPH2, R = Ph, Cy) phosphanes to give diphosphanes of type R4P2 (R = Ph, Cy, iBu) and oligophosphanes R4P4, R5P5 (R = Ph, Cy), respectively. Methylation of 17b+ and subsequent deprotonation reaction with LDA affords the cationic NHO (N-heterocyclic olefin) 35+ of which the gold complex 36+ is readily accessible via the reaction with AuCl(tht).
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46

Schwedtmann, Kai, Robin Schoemaker, Felix Hennersdorf, Antonio Bauzá, Antonio Frontera, Robert Weiss, and Jan J. Weigand. "Cationic 5-phosphonio-substituted N-heterocyclic carbenes." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-221859.

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2-Phosphanyl-substituted imidazolium salts 2-PR2(4,5-Cl-Im)[OTf] (9a,b[OTf]) (4,5-Cl-Im = 4,5-dichloro-1,3-bis(2,6-di-isopropylphenyl)-imidazolium) (a: R = Cy, b: R = Ph) are prepared from the reaction of R2PCl (R = Cy, Ph) with NHC 8 (4,5-dichloro-1,3-bis(2,6-di-isopropylphenyl)-imidazolin-2-ylidene) in the presence of Me3SiOTf. 5-Phospanyl-substituted imidazolium salts 5-PR2(2,4-Cl-Im)[OTf] (10a,b[OTf]) are obtained in quantitative yield when a slight excess of the NHC 8 is used. 5-Phosphonio-substituted imidazolium salts 5-PR2Me(2,4-Cl-Im)[OTf]2 (14a,b[OTf]2) and 5-PR2F(2,4-Cl-Im)[OTf]2 (16a,b[OTf]2) result from methylation reaction or oxidation of 10a,b[OTf] with XeF2 and subsequent fluoride abstraction. According to our quantum chemical studies the Cl1 atom at the 2-position at the imidazolium ring of dication 14b2+ carries a slightly positive charge and is therefore accessible for nucleophilic attack. Accordingly, the reaction of 14a,b[OTf]2 and 16a,b[OTf]2 with R3P (R = Cy, Ph) affords cationic 5-phosphonio-substituted NHCs 5-PR2Me(4-Cl-NHC)[OTf] (17a,b[OTf]) and 5-PR2F(4-Cl-NHC)[OTf] (18a,b[OTf]) via a SN2(Cl)-type reaction. A series of transition metal complexes such as [AuCl(5-PPh2Me(4-Cl-NHC))][OTf] (19[OTf]), [CuBr(5-PPh2Me(4-Cl-NHC))][OTf] (20[OTf]), [AuCl(5-PPh2F(4-Cl-NHC))[OTf] (21[OTf]) and [RhCl(cod)(5-PPh2Me(4-Cl-NHC))][OTf] (23[OTf]) are prepared to prove the coordination abilities of carbenes 17b[OTf] and 18b[OTf]. The isolation of a rare example of a tricationic bis-carbene silver complex [Ag(5-PPh2Me(4-Cl-NHC))2][OTf]3 (22[OTf]3) is achieved by reacting 14b[OTf] with Cy3P in the presence of AgOTf. NHC 17b[OTf] represents a very effective dehydrocoupling reagent for secondary (R2PH, R = Ph, Cy, iBu) and primary (RPH2, R = Ph, Cy) phosphanes to give diphosphanes of type R4P2 (R = Ph, Cy, iBu) and oligophosphanes R4P4, R5P5 (R = Ph, Cy), respectively. Methylation of 17b+ and subsequent deprotonation reaction with LDA affords the cationic NHO (N-heterocyclic olefin) 35+ of which the gold complex 36+ is readily accessible via the reaction with AuCl(tht).
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47

Sun, Li-Ping. "Syntheses of heterocyclic compounds via diversity-oriented approach and microwave-assisted solid-phase combinatorial chemistry /." View abstract or full-text, 2004. http://library.ust.hk/cgi/db/thesis.pl?CHEM%202004%20SUN.

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48

Pchalek, Karin Chemistry Faculty of Science UNSW. "Design and synthesis of new ligands and heterocycles from activated indoles." Awarded by:University of New South Wales. School of Chemistry, 2004. http://handle.unsw.edu.au/1959.4/20584.

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For the purpose of incorporating indoles into organometallic complexes for catalysis, as well as in the generation of new heterocyclic systems, various reactions have been carried out at C2, C6 and C7 of the indole system. In order to achieve this, 3-substituted 4,6-dimethoxyindoles and 6-hydroxy- 4-methoxyindoles were necessary as starting materials. Consequently, a lithium-bromide-templated one-pot procedure for the synthesis of some 3-substituted 4,6-dimethoxyindoles and a selective demethylation procedure for 3-substituted 6-hydroxy-4-methoxyindoles were developed. Various kinds of novel methylene-bridged bi-, tri-, and tetradentate pyridyl-indole ligands were synthesised via Vilsmeier-Haack, Friedel-Crafts or electrophilic addition reactions on the indole heterocycle. However, their metal complexing properties were generally weak and variable. Nevertheless, some of the tridentate pyridylindole ligands showed strong anion binding to halides, whereas a remarkable ligand transformation occurred with a bidentate 2-pyridylindole ligand and zinc(II), giving a substituted indolo[2,3-c]pyrrolo-[3,2,1-ij]quinoline system. Two new types of tetradentate Schiff base ligands were prepared from 2-formyl-indoles and 7-formyl-6-hydroxyindoles, and diamines. These preformed ligands were reacted with first- and second-row transition metals to give neutral metal complexes. Novel heterocyclic systems such as 4H-pyrrolo[3,2,1-ij]quinolines, 3H-pyrrolo-[1,2-a]indoles, and 1H-furo[2,3-g]indoles were synthesised from 2-formyl-, 7-formyl-, and 6-hydroxyindoles, utilising mainly intra-molecular Wittig reactions, Claisen-Schmidt condensations or acid- and base-catalysed cyclisations. A common feature of the prepared 4H-pyrrolo[3,2,1-ij]quinolines and 3H-pyrrolo-[1,2-a]indoles was their intense fluorescent character, which was examined as well.
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49

Majeed, Zulfiqar. "The reactions of directly related tellurium and selenium heterocyclic compounds with triiron dodecacarbonyl." Thesis, Aston University, 1999. http://publications.aston.ac.uk/9622/.

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The reactions of directly related tellurium and selenium heterocyclic compounds with triiron dodecacarbonyl are described. The reaction of 2-telluraphthalide, C8H8OTe with [Fe3(CO)12 gave [Fe{C6H4(CH2)Te}(CO)3]2, (1). An iron atom has inserted into the telluracyclic ring, and it is probable that one co-ordinated CO ligand arises from the initially organic carbonyl group. X-ray analysis of compound (1) showed that the compound has a Fe2Te2 core, which is achieved by dimerisation. The reaction of telluraphthalic anhydride, C8H402Te with [Fe3(CO)12] gave a known, but unexpected, organic phthalide product, C8H602, which was confirmed by X-ray crystallography. Selenaphthalic anhydride,  C8H4O2Se gave intractable products on reaction with [Fe3(CO)12], 2-selenaphthalide, C8H6OSe, on reaction with [Fe3(CO)12] gave a major product [Fe2{C6H4(CH2)Se}(CO)6], (2) and a minor product [Fe3{C6H4(CH2)Se}(CO)8], (3) which is an intermediate in the formation of (2). X-ray analysis of (2) shows that compound (2) is very similar to (1) except that the 18 electron rule is satisfied by co-ordination of a Fe(CO)3 moiety, rather than dimerisation. Compound (3), also studied by X-ray crystallography, differs from (2) mainly in the addition of an Fe(CO)2 moiety. Telluraphtbalic anhydride, C8H402Te, and selenaphthalic anhydride, C8H402Se, are both monoclinic and crystallise in space group P21/n. 2-Selenaphthalide, C8H402Se, is also monoclinic, space group P21/C. The reactions of the following compounds (l,3-dihydrobenzo[c]selenophene, 1,3,7,9-tetrahydrobenzo[1,2c; 4,5c'] ditellurophene, dibenzoselenophene, phenoxselenine, 3, 5-naphtho-1-telluracyclohexane and 3,5-naphtho-1-selenacyclohexane) with [Fe3lCO)12] are reported. It is unfortunate that the above compounds do not react under the conditions employed; this may be due to differing degrees of ring strain. 1,8-bis(bromomethyl)naphthalene, C12H10Br2 is monoclinic and crystallises in space group C2/c. 1,1-diiodo-3,5-naphthotelluracyclohexane, C12H10TeI2 and 3,5-naphtho-l-telluracyclohexane, C12H10Te are monoclinic and crystallise in space group P21/c. 3,5-naphtho-l-selenacyclohexane, C12H10Se and 2,2,8,8-tetraiodo-1,3,7,9-tetrahydrobenzo[1,2c;4,5c']ditellurophene are also monoclinic, space group P21/a. The syntheses of intramolecular stabilised organo-tellurium and selenium compounds are reported, having a general formula of REX (where R = phenylazophenyl; E = Se, Te; X = electronegative group, for example C1, Br or I). The crystal structures of R'TeBr, RTeI, RSeCI, RSeCI/I and RSeI (where R = phenylazophenyl) are reported. The tellurium containing X-ray structures are triclinic and have a space group P-1. The selenium containing X-ray structures are monoclinic with space group P21/n. The inclusion of nitrogen in selenium heterocycles provides access to an entirely new area of organometallic chemistry. The reaction of 2-methylbenzoselenazole with [Fe3(CO)12] gave [Fe2{C6H4(NCH2CH3)Se}(CO)6]. The reactions of 2-(methyltelluro)benzanilide or 2-(methylseleno)benzanilide with [Fe3(CO)12] gave reaction products [Fe2(μTeMe)2(CO)6] and [Fe2 (μ-SeMe)2(CO)6] respectively, which were confmned by X-ray crystallography. The use of Mossbauer spectroscopy on the products obtained from the reactions of heterocyclic compounds with [Fe3(CO)12] can give useful information, for example the number of iron sites and the environments of these iron sites within the products.
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50

Brown, S. M. "The chemistry and conformational analysis of some normal and medium ring alicyclic and heterocyclic compounds." Thesis, University of Huddersfield, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.354322.

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