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Dissertations / Theses on the topic 'Metal Substituted'

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Published: 6 September 2023

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1

Zhao, Ningfeng Eichhorn David M. "Cyano-substituted polypyrazolylborate metal complexes." Diss., Click here for available full-text of this thesis, 2005. http://library.wichita.edu/digitallibrary/etd/2005/d019.pdf.

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Thesis (Ph.D.)--Wichita State University, College of Liberal Arts and Sciences, Dept. of Chemistry.
"December 2005." Title from PDF title page (viewed on February 8, 2007). Thesis adviser: David Eichhorn. Includes bibliographic references (leaves 123-128).

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2

O'Sullivan, Julie Ann. "Metal complexes of trimethylsilyl substituted cyclooctatetraenes." Thesis, University of Sussex, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.361361.

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3

Hopman, Martyn. "Organometallic compounds with bulky, phenyl-substituted, or derived donor-substituted ligands." Thesis, University of Sussex, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285105.

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4

Zanini, Margherita. "Transition metal-catalyzed reactions of heteroatom-substituted alkynes." Doctoral thesis, Universitat Rovira i Virgili, 2020. http://hdl.handle.net/10803/670898.

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La catàlisi homogènia d'or(I) és una eina per a la construcció de complexitat molecular mitjançant l'activació selectiva d'enllaços múltiples C-C. El nostre grup ha desenvolupat una sèrie de reaccions d'alquins amb alquens catalitzades per or(I) tant en forma intramolecular com intermolecular. Aquestes reaccions s’inicien amb l'atac nucleofílic del doble enllaç a l'alquí per formar un intermedi tipus ciclopropil carbé d'or(I) que evoluciona per donar diferents productes. En aquesta tesi doctoral es descriu una sèrie de noves reaccions intermoleculars de alquens amb alquins substituïts amb heteroàtoms catalitzades per or(I). A més, es presenten els estudis mecanístics corresponents, realitzats mitjançant experiments i càlculs DFT. En les reaccions entre bromolaquins i alquens catalitzades per or(I), inicialment es genera un 1-brom ciclopropil carbé d'or(I) que evoluciona a través d'un catió bromoni ciclic per formar un vinilidè d'or(I) o en un catió vinilidilareni estabilitzat per or. Els càlculs DFT demostren que aquests dos intermedis són confòrmers de la mateixa espècie però tenen diferent reactivitat. D'una banda, el vinilidè d'or(I) pot participar en reaciones d'activació C-H o de hidroarilació, mentre que el catió vinilidilareni participa en transposicions 1,2 de l'areni per a formar un triple enllaç. A més, els alquinil èters terminals participen en cicloaddicions [2 + 2] amb alquens per formar ciclobutens que poden convertir-se fàcilment en les corresponents ciclobutanones.
La catálisis homogénea de oro(I) es una poderosa herramienta para la construcción de complejidad molecular en condiciones suaves mediante la activación selectiva de enlaces múltiples C-C. Nuestro grupo ha desarrollado una serie de reacciones de alquinos con alquenos catalizadas por oro(I), tanto de forma intramolecular como intermolecular. Estas reacciones comienzan con el ataque nucleofílico del doble enlace al alquino para formar un intermedio tipo ciclopropil carbeno de oro(I), que evoluciona para dar lugar a diferentes productos. En esta Tesis Doctoral se describen una serie de nuevas reacciones intermoleculares entre alquenos y alquinos sustituidos con heteroátomos catalizadas por oro(I). Además, se presentan los estudios mecanísticos correspondientes, realizados mediante experimentos y cálculos DFT. En las reacciones entre bromoalquinos y alquenos catalizadas por oro(I), inicialmente se genera un 1-bromo ciclopropil carbeno de oro(I) que evoluciona a través de un catión bromonio cíclico para formar un vinilideno de oro(I) o un catión vinilidilarenio estabilizado por oro. Los cálculos DFT demuestran que estos dos intermedios son confórmeros de la misma especie pero tienen diferente reactividad. Los vinilidenos de oro(I) pueden participar en reacciones de activacion C-H o de hidroarilación, mientras que los cationes vinilidilarenio participan en transposiciones 1,2 del areno para formar enlaces triples.
Homogeneous gold(I) catalysis is a powerful tool for the construction of molecular complexity under mild conditions by mean of the selective activation of C-C multiple bonds. Our group developed a series of gold(I)-catalyzed reactions of alkynes with alkenes both in intramolecular and intermolecular settings. These reactions start with the nucleophilic attack of the double bond on the alkyne to form a cyclopropyl gold(I) carbene intermediate that than rearranges into a variety of products. In this Doctoral Thesis we present a series of new gold(I)-catalyzed intermolecular reactions of heteroatom-substituted alkynes with alkenes and the mechanistic investigation we performed by means of experimental work and DFT calculations. In the gold(I) catalyzed reactions of bromoalkynes with alkenes, the 1-bromo-cyclopropyl gold(I) carbene initially formed rearranges into gold(I) vinylidenes and vinylidenephenonium gold(I) cations passing through a cyclic bromonium intermediate. DFT calculations demonstrated that these two reactive intermediates are conformers of the same species but have different reactivity. On one side gold(I)-vinylidenes can undergo hydroarylation or C-H insertion, while vinylidenephenonium gold(I) cations easily undergo 1,2-aryl shift forming a triple bond. Moreover, we found that terminal alkynyl ethers are undergoing efficiently [2+2] cycloaddition with alkenes to form cyclobutene derivatives that can be easily transformed into the corresponding cyclobutanones.

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5

Wang, Junwei. "Metal-based approaches to C(1)-substituted glycals." Thesis, University of Bristol, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.503863.

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A new metal-based method to synthesize C(1)-substituted glycals has been developed. Starting with the obtained substituted C-glycals, the possibility of a stereocontrolled addition (via azidoselenation) to form β-C-substituted-2-aminoglycosides has been investigated. Instead of forming the expected C-glycosyl derivatives of 2-amino sugars, an inseparable mixture of diastereomers, which were derived from the corresponding C(1)-allylated glycals, has been obtained.

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6

Rivers, Christopher John. "Transition metal complexes incorporating trialkylsilyl substituted pentalene ligands." Thesis, University of Sussex, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.289228.

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7

Zenonos, Christianna. "Synthesis and characterisation of metal substituted microporous materials." Thesis, University College London (University of London), 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.405414.

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8

Visscher, Arne. "Fluorescence Studies of Amine-substituted Azaanthracene Metal Complexes." Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2016. http://hdl.handle.net/11858/00-1735-0000-0028-87CC-A.

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9

Cairns, Gareth Alan. "Novel aspects of alkyne substituted transition metal complexes." Thesis, University of Bath, 1998. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.242813.

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10

Baxter, Paul N. W. "Substituted #alpha#-diimine complexes of group VI metal carbonyls." Thesis, University of Kent, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.279680.

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11

Zhang, Guangya. "Synthesis and characterization of metal substituted colloidal silicate-1." Licentiate thesis, Luleå tekniska universitet, 1996. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-25696.

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12

Kinder, James D. "Synthesis and characterization of methoxy-substituted tribenzocyclotriynes and their metal complexes." Case Western Reserve University School of Graduate Studies / OhioLINK, 1992. http://rave.ohiolink.edu/etdc/view?acc_num=case1060108138.

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13

Thomas, Jaron Michael. "On Metal synthesis of Some Substituted Rhenium and Manganese Complexes." TopSCHOLAR®, 2012. http://digitalcommons.wku.edu/theses/1225.

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Heterocyclic organic and organometallic compounds (i.e. polypyrrole), and their derivatives, have been of great interest for conductive polymers due to their novel properties and environmental stability as compared to their non-aromatic analogs (i.e. polyacetylene). Our current interest focus upon the potential role of metal ligand bound pyridazines as the next generation of electronic devices that utilize the metal ligands bound to organics as the semiconducting material. Pyridazine is a 6-membered aromatic ring with two adjacent nitrogen atoms. These are promising candidates for a variety of materials and commercial applications; but they are difficult to get a metal ligand to fuse to the aromatic ring. Our recent efforts focused in attaching Rhenium and Manganese ligands/substituents (process in which is called doping) that would cause oxidation to occur to our polymer making it a p-type polymer. Since p-type polymers charge carriers leave a vacancy that does not delocalize completely. This vacancy (known as a hole) or a radical cation that only partially delocalizes over several monomeric units causing them to be structurally deformed. This deformed structure is at a higher energy than that of an undoped polymer. Typical carriers in organic semiconductors are holes and electrons in a π-orbital. So when these molecules of π-conjugated systems have a π-bond overlap (or π- stacking), electrons can move via these π-electron clouds overlapping thus causing an electrical current. Our worked focused on the synthesis of pyridazines and their organometallic rhenium complexes and polymer research. Several aryl-substituted 5,6-fused pyridazines have been synthesized but none have been documented until this study. The main goal of the research was to fully characterize the general synthesis of furan containing organometallic complexes, [M(CO)3{η5-1,2-C5H3(CC4H3ON)(CC4H3ON)}] (M = Re or Mn) (4B). We successfully characterized the ability to attach a metal organic ligand to pyridazine though IR and NMR. However, when attempts were made to recrystallize our product, we yielded an orange-brown, block like crystal of 1,2- C5H3(CC4H3ONH)(CC4H3ON) (5) in which our metal ligand group fell off and we were left with pyridazine and inorganics. Though, we successfully got an X-ray characterization and electronic studies of compound 5 which are reported herein.

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14

Gardner, Adrian Michael. "Spectroscopy of substituted benzene molecules and metal rare gas interactions." Thesis, University of Nottingham, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.606296.

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The consistency of the labelling and assignments of the vibrations of the monosubstituted benzenes in the ground electronic state are investigated in this thesis. In doing so, many inconsistencies are uncovered, the origin of which is determined to be a result of the inherent problems in the previously employed assignment schemes. As a consequence, a new assignment scheme based on the vibrations of tluorobenzene is proposed. The SI electronic states of toluene and a -trideuterated toluene (toluene-d3) are investigated using resonance enhanced multi photon ionization, REMPI, spectroscopy. Using many of the observed SI vibrational levels as intermediates, two-colour, zero kinetic energy (ZEKE) spectroscopy has been employed in order to investigate the cationic ground states of these two toluene isotopologues. The vibrations are assigned using the nomenclature proposed in this thesis, and the activity of the vibrations in the REMPI and ZEKE spectra are discussed. Using high level ab initio techniques, potential energy curves, PECs, are calculated for the metal cation/rare gas, M+-RG (M = B, AI, Ga, and In) complexes. From these, spectroscopic parameters are derived, which are compared to previously reported experimental and theoretical values. The interactions between the moieties are examined by analyzing the orbital wavefunctions. The trends in the spectroscopic parameters determined for these complexes are compared with those previously determined for the RG complexes of the alkali metal, and the alkaline earth metal cations. Finally, the PECs of the ground electronic states of the coinage metal/rare gas complexes are calculated using high level ab initio techniques, with the interactions which occur within these complexes investigated

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15

Franklin, Ilona Louise. "Studies of metal substituted alumino-phosphates and other related systems." Thesis, University College London (University of London), 2005. http://discovery.ucl.ac.uk/1445536/.

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The research within this thesis has concentrated around the identification and catalytic understanding of the acid and redox properties of a series of metal substituted aluminophosphates, silicoaluminophosphates and polyoxometalates. The aim being to understand how the active metal sites were co-ordinated, to what degree of substitution had been successfully achieved and finally the direct relation this information had in understanding the degree of reaction for the various catalytic processes. In most part hydrothermal synthesis was employed, the exception being in the case of the polyoxometalate and polyoxometalate layered double hydroxide synthesis. Characterisation was achieved through the use of many analytical techniques predominantly X-ray diffraction (XRD) and extended X-ray spectroscopy (XAS). In total, four commercially important reactions were studied. Firstly, the shape selective and redox properties associated with (a) the substitution of different metal ions within the same aluminophosphate framework and (b) the substitution of the same metal ion within different aluminophosphate frameworks were characterised and investigated for the methanol to olefin (MTO) reaction to demonstrate the activity and selectivity of different frameworks in the production of a range of olefins. Secondly, several transition metal ion-exchanged zeolites and aluminophosphates were synthesised, characterised and subsequently analysed for the hydroxylation of phenol. Here temperature effects were also investigated to see what, if any effect it had upon the final conversion of phenol. Thirdly, a series of bifunctional platinum impregnated silicoaluminophosphate (Pt/SAPO) and metal substituted aluminophosphate (Pt/MeAlPO) catalysts were synthesised, characterised then investigated to understand how their acidic nature effected the catalytic activity and selectivity for the hydroisomerisation of n-heptane. Finally, the properties of several cobalt-substituted polyoxometalates (POM's) and polyoxometalate pillared layered double hydroxides (POM-LDH's) were studied and investigated for their catalytic activity for the oxidation of cyclohexane with molecular oxygen in the presence of TBHP.

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16

Ueta, Kento. "Development of Novel meso-Heteroatom Substituted Corroles." Doctoral thesis, Kyoto University, 2021. http://hdl.handle.net/2433/263482.

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17

Toader, Marius. "Self-assembled molecular arrays of distinct types of substituted metal phthalocyanines on crystalline metal substrates." Doctoral thesis, Universitätsbibliothek Chemnitz, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-100419.

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Trotz einer Vielzahl von Forschungsarbeiten auf dem Gebiet der Phthalocyanin-basierten organischen Verbindungen fehlt nach wie vor ein umfassendes Verständnis des Zusammenspiels zwischen strukturellen und elektronischen Eigenschaften, die sich bei der Abscheidung dieser Stoffe auf anorganische kristallinen Substraten ausbilden. Vor diesem Hintergrund wurden für die vorliegende Arbeit vier metallbasierte Phthalocyanine ausgewählt und mittels organischer Molekularstrahl-Abscheidung (OMBD) im Ultrahochvakuum (UHV) auf Ag (111) Einkristalle adsorbiert. Für die anschließende eingehende Untersuchung dieser Proben wurden insbesondere Rastertunnelmikroskopie (STM) und -spektroskopie (STS) angewandt. Ergänzend kamen Ultraviolett- und Röntgen-Photoelektronenspektroskopie (UPS und XPS) zum Einsatz, wodurch komplementäre Informationen gewonnen wurden. Die aus diesen Untersuchungen resultierenden Ergebnisse liefern einen wesentlichen Beitrag zum oben genannten Forschungsgebiet. Die in dieser Arbeit untersuchten Metall-Phthalocyanine (MePc) wurden so ausgewählt, dass eine möglichst große Vielfalt an geometrischen und elektronischen Eigenschaften abgedeckt wurde. Planare cobaltbasierte Phthalocyanin-Moleküle wurden in zwei Konfigurationen untersucht: einerseits das protonierte CoPc, das sich als organischer p-Halbleiter verhält, und andererseits das vollständig fluorinierte F16CoPc, das n-Halbleitereigenschaften besitzt. Bei beiden Systemen zeigte sich an der Position des Cobaltions eine Kopplung zwischen den Molkülorbitalen des Adsorbats und den Elektronenzuständen des Substrates. Das nichtplanare Zinn-Phthalocyanin ist von besonderem Interesse aufgrund seiner beiden möglichen Adsorptionskonformationen up und down, bei denen sich das Sn-Ion oberhalb beziehungsweise unterhalb des Phthalocyaninliganden befindet. Damit stellt dieses System einen möglichen Kandidaten für Anwendungen als molekularer Schalter oder als Speichereinheit dar. In der vorliegenden Studie werden lokalisierte Schaltvorgänge einzelner Moleküle zusammen mit der Möglichkeit einer kontrollierten molekularen Nanostrukturierung gezeigt. Lutetium (III) bisphthalocyanin wurde ausgewählt als Vertreter einer neuen Gruppe von MePc, die eine Sandwichstruktur ausbilden, bei der zwei π-konjugierte Phthalocyaninliganden über ein Seltenerd-Ion miteinander verbunden sind. Die Untersuchung dieses Systems liefert wichtige neue Erkenntnisse, wie zum Beispiel ein umfassendes Verständnis der Vorgänge bei der Selbstassemblierung innerhalb der ersten und zweiten organischen Monolage. Zudem wurde bei der Charakterisierung des Tunneltransports durch einzelne Moleküle mittels STS ein negativer differentieller Widerstand (NDR) gefunden, der von der Anzahl molekularer Lagen abhängt.

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18

Townsend, James Alan. "Synthesis, characterization and application of N-substituted and C-substituted nickel cyclam cataylsts in hydrodehalogenation reactions." Diss., Manhattan, Kan. : Kansas State University, 2009. http://hdl.handle.net/2097/1469.

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19

Robinson, Matthew Peter. "Ortho-substituted arylsilanes in oxidative gold catalysis." Thesis, University of Edinburgh, 2018. http://hdl.handle.net/1842/31394.

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Organometallic compounds derived from tin, boron, and zinc, have been used extensively in transition metal-catalysed cross-coupling, and continue to hold status as the go-to reagents to form new carbon-carbon bonds. Recently, organosilicon compounds have emerged as an attractive alternative to these established reagents, benefitting from low toxicity, low cost, and general ease of handling. While the fundamental reactivity of arylsilane reagents (Ar-SiR3) is well known, their role in transition metal-catalysed reactions is generally less well studied. This thesis comprises an investigation into the effect of ortho-substitution of these arylsilane reagents, and specifically, their application in gold-catalysed direct arylation. In Chapter 2, the transmetalation of these reagents to gold(III) is assessed using a combination of in situ reaction monitoring coupled with kinetic simulations. This allowed a scale of reactivity to be constructed for a range of structurally diverse arylsilanes, and uncovered that more sterically hindered arylsilanes actually exhibit accelerated rates of transmetalation. In Chapter 3, the reactivity of ortho-substituted arylsilanes in gold-catalysed arylation is addressed. The majority of arylsilanes tested in the previous chapter were found to be unable to undergo coupling, despite the viability of transmetalation having been demonstrated. Slight modification of the ortho-substituent, to incorporate a tethered ligand, was found to have a dramatic effect on reactivity, and allowed the coupling of a variety of substrates. The nature of the ligand, as well as the substitution of the tether was found to have a significant impact on the rate of coupling. Chapter 4 describes the way in which the reactivity of ortho-substituted arylsilanes might be exploited in a 'Catch and Release' protocol for catalyst recovery. This aims to combine the established benefits of homogeneous and heterogeneous catalysis to offer an alternative to current methods of catalyst recycling in industrial chemistry. A number of different 'Catch and Release' mechanisms were considered, and the validity of the concept was demonstrated in a monophasic system.

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20

Hill, Susan Jane. "The synthesis of transition metal substituted aluminophosphate molecular sieves using tetrahalometallates." Thesis, University of Wolverhampton, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337315.

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21

Henney, Roland Patrick Graham. "The transition metal chemistry of some thienyl- and phenyl-substituted pyridines." Thesis, University of Cambridge, 1991. https://www.repository.cam.ac.uk/handle/1810/271903.

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22

Mac, Mahon Colm. "Magnetic and magnetoelastic properties of cerium substituted rare earth transition metal glasses." Thesis, University of Hull, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.395506.

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23

Stepanenko, Vladimir. "Self-Assembly of Bay-Substituted Perylene Bisimide by Ligand-Metal Ion Coordination." Doctoral thesis, kostenfrei, 2008. http://www.opus-bayern.de/uni-wuerzburg/volltexte/2009/3206/.

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24

Neathery, James Leif. "Off-Metal Synthesis of Some Aryl Substituted Rhenium n5-Cyclopenta [C] Pyridazyl Complexes." TopSCHOLAR®, 2009. http://digitalcommons.wku.edu/theses/125.

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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). Our current interests focus upon the potential role of pyridazines in next generation electronic devices that utilize organics as the semiconducting material. Pyridazines, 6-membered aromatic rings with two adjacent nitrogens, are promising candidates for a variety of materials and commercial applications. These molecular electronic materials posses several advantages over traditional inorganic semiconducting materials including lower cost of production, higher processibility, and the ability to function on flexible substrates (so called “plastic electronics”). These compounds offer new materials suitable for a variety of real world applications such as Organic Light Emitting Diodes (OLEDs) and Organic Photovoltaic Cell (OPVs). Our recent efforts has been focused on the synthesis of a variety of 5,6-fused ring pyridazines. These fused heterocycles will serve as synthetic models and building blocks for potential organic or organometallic conducting polymers. Our work is focused on the synthesis of pyridazines and their organometallic rhenium complexes and polymer research. Several aryl-substituted 5,6-fused ring pyridazines have been synthesized and characterized. A pyridazyl complexe of rhenium was synthesized in three steps beginning with a 5,6-fused pyridazine. Off-metal synthesis and characterization of [Re(CO)3{1,2-C5H3(CC6H5N)(CC6H5N)}] and some aryl-substituted pyridazines (1,2-C5H3(CRNH)(CRN); R = C6H5, C4H3S, C8H5S) are reported herein.

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25

Mal, Sib Sankar [Verfasser]. "Synthesis, structure and properties of multi-transition metal-substituted polyoxotungstates / Sib Sankar Mal." Bremen : IRC-Library, Information Resource Center der Jacobs University Bremen, 2008. http://d-nb.info/1034982680/34.

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26

Hayton, Lynda Julie. "Matrix ESR studies of metal atoms with silicon substituted alkenes and related compounds." Thesis, University of Bristol, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.325887.

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27

Thornberry, Matthew P. "Synthesis, Properties, and Reactivity of Pentafluorophenyl Substituted Cyclopentadienes and Their Transition Metal Complexes." Diss., Virginia Tech, 2001. http://hdl.handle.net/10919/28539.

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Substituent effects in eta5-cyclopentadienyl (Cp) transition metal complexes have been intensely studied since the discovery of the first such complex, ferrocene. Modifications of the Cp ligand framework effect changes in the physical properties and chemical reactivity of the coordinated transition metal. This concept is useful when applied to catalysis mediated by Cp complexes, because the performance of the catalyst can be markedly improved using well-chosen ligand substituents. Studies of electronic substituent effects ideally employ a wide range of electron-donating and electron-withdrawing groups. Unfortunately, most of the available electron-withdrawing groups suffer from problems with Cp ligand synthesis, Cp anion stability, and electron-withdrawing group stability under catalytic conditions. This dissertation shows that the pentafluorophenyl (C6F5) substituent is highly electron-withdrawing but avoids all of these problems. Several new C6F5-substituted cyclopentadienes are prepared by the reaction of sodium cyclopentadienide and hexafluorobenzene (C6F6) under varying conditions. Corresponding C6F5-substituted cyclopentadienyl ligands (sodium salts) are obtained upon deprotonating the dienes with NaH. Complexes of Mn(I), Re(I), Fe(II), Co(II), Zr(IV) are synthesized by reacting these ligands with transition metal halides. The acidities of several C6F5- and C5F4N-substituted cyclopentadienes and indenes are measured using 19F NMR spectroscopy. The electron-withdrawing fluorinated aryl groups have a substantial acidifying effect. The identity and number of substituents (C6F5, C5F4N, CH3, and t-Bu), the position of the substituents on the cyclopentadiene, and the intramolecular (vicinal) steric effects also influence acidity. The electron-withdrawing ability of the C6F5 group is also characterized by infrared spectroscopic analysis of substituted CpM(CO)3 (M = Mn(I) and Re(I)) and electrochemical analysis of substituted ferrocenes. X-ray crystal structures of several C6F5-substituted Cp complexes reveal interesting structural motifs, including pi-stacking of the C6F5 substituents, Cp-M bond elongation, and CO-C6F5 interactions. In addition, dynamic Cp-C6F5 and Cp-M rotational barriers are measured by variable temperature NMR spectroscopy. Finally, ethylene polymerizations and ethylene/1-hexene copolymerizations are conducted using C6F5- and C6H5-substituted zirconocene dichlorides as catalysts. Contrary to findings published elsewhere, this study shows that substituent electronic effects induce substantial changes in comonomer incorporation.
Ph. D.

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28

Simpson, Linda. "Trivalent group 13 metal complexes of N-substituted-3-hydroxy-2-methyl-4-pyridinones." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/28885.

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The compounds tris(N-ռ-propyl-3-hydroxy-2-methyl-4-pyridinonato) aluminum(III), -gallium(III), and -indium(III) and tris(N-ռ-butyl-3-hydroxy-2-methyl-4-pyridinonato)aluminum(III), -gallium(III), and -indium(III) were synthesized. All six compounds were prepared via the metal template effect. They were characterized by IR, FAB-MS, ¹H NMR, ²⁷Al NMR, and elemental analysis. Three of the six complexes were studied by single-crystal X-ray diffraction. They formed trihydrates, unlike their N-methyl and N-ethyl analogues, which formed dodecahydrates. The ռ-butyl complex Al(C₁₀H₁₄N0₂)₃‧3H₂0 (1) and ռ-propyl complexes Al(C₉H₁₂N0₂)₃‧3H₂0 [2], and Ga(C₉H₁₂N0₂)₃‧3H₂0 {3} were basically isostructural, crystallizing in the space group P3 with the following crystal parameters for 1, [2], and {3}: α= 15.885 (1) ([15.328 (1)], {15.367 (2)}) Å, c = 7.280 (8) ([7.2321 (2)], {7.256 (2)}) Å, Z = 2. The data were refined by using 1280 ([1377], {1802}) reflections with I>3σ(I) to R and Rա values of 0.047 ([0.057], {0.055)) and 0.061 ([0.077], {0.081}), respectively. The complexes exist as the rigidly fac geometries with infinite chains of hydrogen bonds parallel to the c axis.
Science, Faculty of
Chemistry, Department of
Graduate

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29

Moorlag, Hendrik. "Chiral [alpha]-substituted [alpha]-hydroxy acids (stereoselective) synthesis using transition metal and enzyme catalysis /." [S.l. : [Groningen : s.n.] ; University Library Groningen] [Host], 1991. http://irs.ub.rug.nl/ppn/290738156.

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30

Zhu, Zhi Huai. "The metal-insulator transition in Mn-substituted Sr₃Ru₂O₇ by a photoemission study." Thesis, University of British Columbia, 2009. http://hdl.handle.net/2429/13906.

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We have studied the metal-insulator transition (MIT) in Mn-substituted Sr₃Ru₂O₇ by x-ray photoemission (XPS) and angle-resolved photoemission spectroscopy (ARPES). In XPS, both the surface- and bulk-sensitive spectra show a two-peak structure, corresponding to the well screened and the unscreened excitations. The evolution of the well screened peak with Mn is that the higher the concentration of Mn impurities, the lower the intensity of the peak, indicating that the screening channels are determined by the metallic property of a system. In ARPES, a strong doping dependence is also observed for the Fermi surface, which loses the 2D sheet associated with the dxy band and reduces to the 1D dxz/yz Fermi surfaces, as the system changes from metal to a Mott insulator. As for the band dispersion, we see that the dxy band shifts in energy toward the chemical potential, becoming degenerate with the dxz/yz bands, to the point of being indistinguishable. A nesting vector (0.33, 0.33, 0) has been determined from the Fermi surface of the 10% Mn doped sample, as in response to-or alternatively inducing-a charge/orbital ordering across the Mott transition. The opening of an energy gap is observed below the MIT both as a function of temperature and Mn substitution. To obtain a microscopic understanding of the MIT, we have performed a local-density approximation calculations for the electronic structures of Sr₃Ru₂O₇ and found that spin-orbital coupling induces an unexpected magnetic anisotropy. This might play a key role in the emergence of the MIT and magnetic superstructure in Mn-substituted Sr₃Ru₂O₇, as well as the nematic behavior in the parent compound.

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31

Mukherjee, Sudarshana. "Control over Dimensionality and Magnetic Properties in Metal Complexes formed with Substituted Salicyl Ligands." [S.l. : s.n.], 2008. http://digbib.ubka.uni-karlsruhe.de/volltexte/1000009757.

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32

Lanez, Touhami. "Synthesis of pyrindine and cyclopent[c]azepine derivatives by photochemical and acid-catalysed degradation of substituted ferrocenes." Thesis, University of Strathclyde, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.278447.

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33

Layer, Teresa. "Synthesis and characterisation of novel phosphorus and selenium substituted carbonyl clusters of ruthenium and osmium." Thesis, University of Cambridge, 1993. https://www.repository.cam.ac.uk/handle/1810/272563.

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34

Smit, Theodoor Martin. "Heteroatom substituted bis(imino)pyridine and bis(phenoxy-amine) transition metal complexes for olefin polymerisation." Thesis, Imperial College London, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.420626.

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35

Delf, Alexander Robert L. "Electrochemical and spectroelectrochemical characterisation of cyano and trifluoromethyl substituted polypyridines and their transition metal complexes." Thesis, University of Edinburgh, 2011. http://hdl.handle.net/1842/5026.

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This thesis is concerned with the electrochemical and spectroelectrochemical characterisation of cyano (CN) and trifluoromethyl (CF3) substituted polypyridine ligands and their metal complexes. The ligands investigated were X-CN-py (X = 3, 4 and 5, py = pyridine), X,X´-(CN)2-bpy) (X,X´ = 3,3´, 4,4´ and 5,5´ bpy = 2,2´- bipyridine) and X,X´-(CF3)2-bpy (X,X´ = 3,3´, 4,4´ and 5,5´). The Pt(II) complexes of the X-CN-py and X,X´-(CN)2-bpy ligands were studied along with the Fe(II) complexes of the X,X´-(CN)2-bpy and X,X´-(CF3)2-bpy ligands. Electrochemical studies of the X-CN-py ligands indicated that 2-CN-py and 4-CN-py have one reversible 1e- reduction and 3-CN-py has one quasi-reversible reduction. 4-CN-py is more easily reduced than 2-CN-py. EPR experiments on [2-CN-py]1- and [4-CN-py]1- combined with DFT calculations have indicated that the semi-occupied molecular orbital (SOMO) is delocalised over the entire molecule. The complex [Pt(4-CN-py)2Cl2] undergoes two reversible 1e- reductions, attributed to the sequential reduction of the two 4-CN-py ligands. [Pt(3-CN-py)2Cl2] was found to exhibit one irreversible reduction. The electrochemistry of the X,X´-(CN)2-bpy ligands indicated that 3,3´-(CN)2-bpy and 5,5´-(CN)2-bpy have two reversible 1e- reductions while 4,4´-(CN)2-bpy has only one reversible 1e- reduction. The reductions of 5,5´-(CN)2-bpy occur at significantly less negative potentials than those in 3,3´ or 4,4´ analogue. In-situ UV/Vis/NIR and EPR experiments on the X,X´-(CN)2-bpy ligands indicate that the reduction electron is delocalised over both the CN-py rings with the SOMO being spread across the entire molecule. [Pt(3,3´-(CN)2-bpy)Cl2] and [Pt(5,5´-(CN)2-bpy)Cl2] undergo two reversible 1e- reductions, attributed to the sequential reduction of the X,X´-(CN)2-bpy ligand. 4,4´-(CF3)2-bpy and 5,5´-(CF3)2-bpy, whose X-ray crystallographically determined structures are reported, both have one reversible 1e- reduction while 3,3´-(CF3)2-bpy exhibits an irreversible reduction. Again the 5,5´ analogue is the most easily reduced. Spectroelectrochemical results indicate that the reduction electron enters a SOMO that is delocalised over both the CF3-py rings. Substitution in the 5,5´ positions is determined to be electronically most significant. Complexes of the general formula [Fe(II)(X2-bpy)3][BF4] (where X = CN or CF3 in the 4,4´ or 5,5´ positions) exhibit three reversible ligand based reduction processes and a metal based oxidation. UV/Vis/NIR and EPR studies have confirmed that the reduction electron in each case enters a molecular orbital that is predominantly based on a bpy ligand. The redox potentials of 4-CN-py and 5,5´-(CN)2-bpy are solvent dependent with 1e- reduction of 4-CN-py and the two 1e- reductions of 5,5´-(CN)2-bpy moving to less negative potentials as the acceptor number (AN) of the solvent increases. A computational model has been developed for the study of the electronic properties of substituted bipyridines using DFT methods. This model has been used to aid the analysis of the EPR and UV/Vis/NIR spectra of the X2-bpys studied.

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36

Smith, Jason Jeffrey. "Spectroscopic studies of metal substituted forms of the zinc enzyme phosphomannose isomerase from Candida albicans." Thesis, University of East Anglia, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.338234.

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37

Priimov, Gleb Urevich. "Synthesis, kinetic and mechanistic studies of substituted 2,2':6',2''-terpyridines and their metal complexes." Thesis, University of Warwick, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.340070.

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38

Aziz, Y. F. A. "The metal complexes of 3-hydroxyflavone and tin(IV) complexes of catechol and substituted catechol." Thesis, University of Reading, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233191.

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39

Huang, Shih-huang. "Synthetic, Mechanistic, and Structural Studies of Polynuclear Metal Clusters and Hydrazido-Substituted Tantalum(V) Compounds." Thesis, University of North Texas, 2010. https://digital.library.unt.edu/ark:/67531/metadc33166/.

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A combined experimental and computational study on the reversible ortho-metalation exhibited by the triosmium cluster Os3(CO)10(dppm) (dppm = 1,1-bis(diphenylphosphino)methane is reported. The conversion of nonacarbonyl cluster HOs3(CO)9[-PhP(C6H4)CH2PPh2] to Os3(CO)10(dppm) is independent of added CO and exhibits a significant inverse equilibrium isotope effect (EIE). Reductive coupling of the C-H bond in HOs3(CO)9[-PhP(C6H4)CH2PPh2] leads to the formation of agostic C-H and two distinct aryl-π species prior to the rate-limiting formation of the unsaturated cluster Os3(CO)9(dppm). Heating the unsaturated dimer H2Re2(CO)8 with Cp*Rh(CO)2 (Cp* = 1,2,3,4,5-pentamethylcyclopentadiene) at elevated temperature affords the new trimetallic clusters H2RhRe2Cp*(CO)9 and HRh2ReCp*2(CO)6, and the spiked-triangular cluster HRhRe3Cp*(CO)14. H2Re2(CO)8 reacts with Cp*2Rh2(CO)2 under identical conditions to furnish H2RhRe2Cp*(CO)9 and HRh2ReCp*2(CO)6 as the principal products, in addition to the tetrahedral cluster H2Rh2Re2Cp*2(CO)8. H2RhRe2Cp*(CO)9 undergoes facile fragmentation in the presence of halogenated solvents and the thiols RSH (where R = H, C6H4Me-p) to afford the structurally characterized products Cp*Rh(-Cl)3Re(CO)3, S2Rh3Cp*(CO)4, Cp*Rh(-Cl)(-SC6H4Me-p)2Re(CO)3, and Cp*Rh(-SC6H4Me-p)3Re(CO)3. The new hydrazido-substituted compounds TaCl(NMe2)3[N(TMS)NMe2] (TMS = tetramethylsilyl) and Ta(NMe2)4[N(TMS)NMe2] have been synthesized and their structures established by X-ray crystallography. The latter product represents the first structurally characterized octahedral tantalum(V) complex containing a single hydrazido(I) ligand in an all-nitrogen coordinated environment about the metal center. The fluxional properties of the amido and hydrazido ligands in these new compounds have been established by VT 1H NMR spectroscopy (VT = variable temperature). Preliminary data using Ta(NMe2)4[N(TMS)NMe2] as an ALD (ALD = atomic layer deposition) precursor for the preparation of tantalum nitride and tantalum oxide thin films are presented.

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40

Kabwe, Kapambwe Peter. "Synthesis, spectroscopic and nonlinear optical properties of metal-free and nickel β substituted binuclear phthalocyanines." Thesis, Rhodes University, 2016. http://hdl.handle.net/10962/3013.

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In this project, nickel and metal-free 4β-(4-tert-butylphenoxy) phthalocyanine, biphenyl bridged binuclear 4-tert-butylphenoxy phthalocyanine and naphthalene bridged binuclear 4-tert-butylphenoxy phthalocyanine have been synthesised. The Z-scan technique has been employed to comparatively study their second order nonlinear optical (NLO) properties. This work, shows that the presence of H-aggregation in binuclear Pcs of metal-free and nickel 4β-(4-tertbutylphenoxy) phthalocyanines do not have an effect on the magnitude of second order nonlinear absorption coefficient (β) as compared to monomeric Pcs. Density functional (DFT) calculations of dipolar/octupolar contributions were performed, in order to explain experimentally determined β values. Spectroscopic and photophysical properties of the synthesised compounds have been determined using a range of different spectroscopic techniques, including magnetic circular dichroism (MCD), time correlated single photon counting spectroscopy (TCSPC), UV-visible absorption spectroscopy, mass spectroscopy and IR Spectroscopy.

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41

Xiao, Xingxing [Verfasser], Anke [Akademischer Betreuer] Weidenkaff, and Rainer [Akademischer Betreuer] Niewa. "Thermoelectric Properties of Alkaline Earth Metal Substituted Europium Titanates / Xingxing Xiao ; Anke Weidenkaff, Rainer Niewa." Darmstadt : Universitäts- und Landesbibliothek, 2021. http://d-nb.info/1225865751/34.

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42

Guven, Sinem. "Construction Of Pyrrolo[1,2-a]pyrazine Structure By Metal Catalyzed Cyclization Of N-propargyl Substituted Pyrroles." Master's thesis, METU, 2013. http://etd.lib.metu.edu.tr/upload/12615582/index.pdf.

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Pyrrolo[1,2-a]pyrazine is one of the isomers of pyrolodiazine family. Pyrrolo[1,2-a]pyrazine possesses a bicyclic heteroaromatic structure that have 10 electrons. It has various biological importances in synthetic chemistry
therefore, many different approaches to generate this skeleton have been developed so far. In this study, our prior aim was to develop a new synthetic methodology for the formation of pyrrolo[1,2-a]pyrazine moiety. In the first part of this focus, the starting compound, methyl 2-(2-methoxy-2-oxoethyl)-1-(prop-2-yn-1-yl)-1H-pyrrole-3-carboxylate was successfully synthesized, then the conversion of the ester group at the lower arm to the amine group was carried out. Heteroatom cyclization catalyzed by CuI afforded the desired substituted pyrrolo[1,2-a]pyrazine structure. In the second part, it was aimed to synthesize new compounds with unusual structures which are not described in the literature
namely, as pyrrolo[1,2-a]pyrazine N-oxide. In this direction, first pyrrole was submitted to Vilsmeier-Haack reaction to attach a formyl group at C-2. Substitution reaction then effectively gave 1-(prop-2-yn-1-yl)-1H-pyrrole-2-carbaldehyde, which was a key molecule to synthesize the aldoxime. AuCl3 catalyzed cyclization of the corresponding oxime afforded pyrrolo[1,2-a]pyrazine N-oxide. In the next step, Sonogashira coupling reactions were carried out to obtain terminal alkynes (RC&equiv
CR'
) starting from 1-(prop-2-yn-1-yl)-1H-pyrrole-2-carbaldehyde. The aim of this part was to study the effect of aryl groups to the activated alkyl functional group by a metal catalyst. In this case, unexpected oxime-oxime transformation was observed, which is unprecedented in the literature

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43

Winter, Ross S. "Understanding the reorganisation of lacunary [γ-SiW10O36]8- during the synthesis of transition metal substituted polyoxotungstates." Thesis, University of Glasgow, 2014. http://theses.gla.ac.uk/5509/.

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One of the biggest challenges in chemistry is the selective synthesis of molecular structures in a controlled and predictive manner. Within polyoxometalate chemistry this is especially true and there is still much left unknown regarding how and why particular architectures form and how specific structures can be selected for. The lacunary Keggin polyoxotungstate K8[γ-SiW10O36]•12H2O is a very versatile starting material in the synthesis of transition metal substituted polyoxometalates. It is capable of undergoing several isomerisations and changes in nuclearity as it reacts, but the process is poorly understood. This thesis examines the interplay between the reaction conditions and the final architectures obtained when using {γ-SiW10O36}, with the intention to understand the mechanisms that underpin its reactivity. Using high pH reaction conditions {γ-SiW10O36} readily reorganised and it was capable of forming some of the most sophisticated transition metals substituted polyoxometalate structures known to date in which three unique Keggin are found concurrently around a cubane-like transition metal core. Furthermore, high pH conditions lead to the discovery of the first clusters containing the previously unreported {γ-SiW9O36} species, which was able to trap a highly transition metal substituted Keggin core. The synthesis of the {γ-SiW9O36} containing cluster was particularly interesting as within the crystallisation, “intermediate” crystals could be obtained which were shown by microscopy to be sacrificial nucleation sites for crystal growth of the final products. The final and intermediate products were composed of isomeric building blocks, which varied only in the positions within the architecture that were occupied by transition metal. Using a limited parameter synthetic approach with only two reaction components, it was shown that we could selectively produce each type of isomer and hence could for the first time control the exact positioning of transition metals within a polyoxometalate. The building blocks were also shown to dimerise when the concentration of transition metal was increased. Using {γ-SiW10O36} it was possible to synthesize {M2(B-β-SiW8)2} clusters (M = Mn, Fe, Co, Ni, Cu, Zn) and use these as clusters as the first known {B-β-SiW8} based starting materials. This opened up the potential for studying the solution phase behaviour of {B-β-SiW8} for the first time in POM history.

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44

Sriramulu, Phenahas Gandu. "On-Metal Synthesis of Some Aryl Substituted Rhenium &#951⁵ 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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45

Lu, Yingdong. "The development of metal catalyzed, one-step approaches to alpha-amino acids, pyrroles and alpha-substituted amides." Thesis, McGill University, 2009. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=66774.

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THE DEVELOPMENT OF METAL CATALYZED, ONE-STEP APPROACHES TO α-AMINO ACIDS, PYRROLES AND α-SUBSTITUTED AMIDES The purpose of this research was to develop new, one pot methods to assemble nitrogen-contained biologically relevant products, such as pyrroles, amido acid derivatives, and α-substituted amines/amides. These products are all generated from readily available building blocks, such as imines, acid chlorides, alkynes, and/or carbon monoxide, and often via metal catalysis. Chapter 2 of this thesis describes how α-phenoxyamides can be used in palladium catalyzed carbonylations to form α-amino acid derivatives, instead of the previously reported synthesis with imines/acid chlorides. Notably, these substrates are analogous of the in situ formed N-acyl iminium salts, but more stable, and in the presence of a palladium(0) complex (Pd2dba3) and Lewis acids can undergo carbon-oxygen bond activation to form palladacycles. Coupling this oxidative addition with carbonylation provides a mild, one step, catalytic route to prepare α-amino acid derivatives in high yield. In chapter 3, we show that α-(3-pyridyloxy)amides can directly undergo oxidative react with palladium catalysts, and be employed in the palladium catalyzed carbonylation to form α-amino acid derivatives. Notably, this reaction requires neither acidic nor basic co-catalysts, and is tolerant to various sensitive substituents. Moreover, this carbonylation reaction can be coupled with alkyne trapping and form pyrroles in one step from α-(3-pyridyloxy)amides and alkynes. Chapter 4 describes an alternative route to readily form pyrroles, via the phosphine mediated coupling of α, β-unsaturated imines and acid chlorides. This provides a novel approach to regioselectively assemble of polysubstituted pyrroles from simple starting materials. The application of this method for the synthesis of lukianol A is also described. In chapter 5, our studies f
Le Développement d'Approches en Un Pot, Catalysées par un Métal de Transition pour la Synthèse d'-Acides Aminés, Pyrroles et d'Amides -SubstituésL'objectif de cette recherche était de dévolopper une nouvelle méthode en un pot pour former des produits biologiquement importants contenant un azote, tels que les pyrroles, les dérivés d'acides aminés et les amines/amides α-substitués. Ces produits sont tous générés à partir de produits de départ facilement disponible, tels que les imines, les chlorures d'acides, les alcynes et/ou le monoxide de carbone, et souvent via la catalyse par un métal de transition.Le chapitre 2 de cette thèse décrit comment les α-phenoxyamides peuvent être utilisés dans les carbonylations catalysées par le palladium pour former des dérivés d'α-acides aminés, au lieu de la synthèse, précédemment reportée, avec des imines et des chlorures d'acides. Ces substrats sont similaires aux sels d'iminiums N-acylés formés in situ mais ils ont l'avantage d'être plus stable, et en présence d'un complexe de palladium(0) (Pd2dba3) et d'un acide de Lewis, ils peuvent subir une activation de liaison carbone-oxygène pour former des palladacyles. Le couplage de cette addition oxydante avec la carbonylation fournit un voie douce et en une étape pour préparer des dérivés d'α-acides aminés avec de hauts rendements.Dans le chapitre 3, nous montrons que, sans l'assistance d'acides de Lewis, les α-(3-pyridyloxy)amides peuvent directement subir une addition oxydante avec un catalyseur de palladium et peuvent être employés dans la carbonylation catalysée par le palladium pour former des dérivés d'α-acides aminés. Cette réaction exige aucuns co-catalyseurs acides ou basiques, et elle tolère de nombreux substituents sensibles. De plus, cette réaction de carbonylation peut se coupler à la cycloaddition avec un alcyne pour former des pyrroles en une é

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46

Clark, Stephen. "Synthesis, crystal structures and mesogenic properties of some transition metal complexes of substituted phenylmalonaldehyde and related compounds." Thesis, University of Hull, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.395685.

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47

Jende, Lars Norman [Verfasser], and Reiner [Akademischer Betreuer] Anwander. "Donor-Substituted Cyclopentadienyl Ligands in Rare-Earth Metal-Based Isoprene Polymerization / Lars Norman Jende ; Betreuer: Reiner Anwander." Tübingen : Universitätsbibliothek Tübingen, 2016. http://d-nb.info/1164168126/34.

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48

Murray, Paul Ross. "Electrochemical and spectroelectrochemical studies on nitro-substituted poly-pyridine derivatives and their transition metal co-ordination complexes." Thesis, University of Edinburgh, 2005. http://hdl.handle.net/1842/11208.

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49

Bankole, Owolabi M., and Tebello Nyokong. "Mercaptopyridine-substituted indium, zinc, and metal-free phthalocyanines: nonlinear optical studies in solution and on polymer matrices." Taylor & Francis Group, 2015. http://hdl.handle.net/10962/d1020313.

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In this article, the nonlinear optical characterizations and optical limiting properties of metal-free (2), zinc (3), and indium (4) tetra 4-(2-mercaptopyridine) phthalocyanines are discussed. Nonlinear optical properties of the samples were evaluated using Z-scan at 532 nm and 10 ns pulse in CHCl3, and doped on poly(bisphenol A carbonate) (PBC) thin films. Thin films for 2, 3, and 4 are represented as 2-PBC, 3-PBC, and 4-PBC, respectively. We observed two-photon absorption (2PA) and strong reverse saturable absorption as the dominant mechanisms at nanosecond laser excitation in solution and thin films. By virtue of the magnitude of absorption coefficients and other nonlinear optical parameters estimated in this work, sample 4 was found to exhibit strongest nonlinear optical properties followed by 3, while 2 is the weakest nonlinear absorber of the studied samples. Large third-order susceptibility (1.46 × 10−9 esu and 7.74 × 10−10 esu) and hyperpolarizability (2.13 × 10−28 and 8.37 × 10−29 esu) were estimated for 4-PBC and 3-PBC, respectively. Our studies show that these molecules are suitable candidates for practical passive optical limiters.
Original publication is available at http://dx.doi.org/10.1080/00958972.2015.1077237

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50

Visscher, Arne [Verfasser], Dietmar [Akademischer Betreuer] [Gutachter] Stalke, and Franc [Gutachter] Meyer. "Fluorescence Studies of Amine-substituted Azaanthracene Metal Complexes / Arne Visscher. Betreuer: Dietmar Stalke. Gutachter: Dietmar Stalke ; Franc Meyer." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2016. http://d-nb.info/1107761859/34.

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