Dissertations / Theses: 'Chiral metal salen complexes'

1

Tucker, S. C. "Towards novel ligands for catalytic asymmetric oxidation." Thesis, University of Oxford, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.242038.

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Zidelmal, Nacim. "SILIPOLYSALEN : étude du greffage par polymérisation contrôlée de complexes de salen sur silicium pour une application en catalyse asymétrique hétérogène." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLS058.

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Les complexes métalliques chiraux de type salen sont connus pour la diversité de leur utilisation en catalyse conduisant à la préparation de nombreux synthons énantio-enrichis. Conformément au concept de chimie verte, l'un des principaux objectifs est d'établir une procédure efficace pour la récupération et la réutilisation de ces catalyseurs. Dans ce contexte, l'objectif de ce travail est de fonctionnaliser la surface du silicium par greffage covalent de ces catalyseurs par polymérisation contrôlée notamment la polymérisation radicalaire par transfert d’atome (ATRP) pour leur récupération et leur réutilisation. Ainsi, des copolymères de styrène contenant 5 à 50 mol% d’un comonomère salen dissymétrique ont été synthétisés par ATRP en solution. Le caractère contrôlé des polymérisations n’est obtenu que lorsque l’incorporation du comonomère salen est inférieure ou égale à 10 mol %.Après complexation au cobalt, les polymères correspondants se sont révélés capables de réaliser une activation coopérative efficace, conduisant au produit ciblé avec des rendements et des sélectivités élevés en tant que catalyseurs dans la réaction de dédoublement cinétique hydrolytique de l’épibromohydrine.Nous avons également réalisé la polymérisation du styrène sur la surface de silicium par ATRP après greffage de l’amorceur. Plusieurs méthodes de greffage de l’amorceur ont été utilisées soit d’une manière directe à partir de la surface hydrogénée, soit indirecte à partir d’une surface acide ou ester. Le styrène a été ensuite efficacement polymérisé en masse avec succès de façon contrôlée sur le silicium, avec des épaisseurs de couche comprise entre 9 et 29 nm déterminées par ellipsométrie et microscopie à force atomique
Chiral metal complexes of salen type are known for their efficient catalytic activity leading to the preparation of enantioselective enriched synthons. In accordance with the concept of green chemistry, one of the main challenge is to establish a procedure for the recovery and reuse of these catalysts. In this context, the objective of this work is to functionalize the silicon surface by grafting these catalysts by controlled polymerization especially by Atom Transfer Radical Polymerization (ATRP) to facilitate their recovery and reuse.Thus, styrene copolymers containing 5 to 50 mol % of an disymmetric salen comonomer were synthesized by ATRP in solution. The controlled nature of the polymerizations is obtained only when the incorporation of the salen comonomer is less than or equal to 10%.After complexation with cobalt, these complexes are shown to be capable of effective cooperative activation, leading to the targeted product with high yields and selectivities as catalysts in Hydrolytic Kinetic Resolution (HKR) of epibromohydrin.Constantio Constantini fratre imperatoris, matreque Galla.We also reported the polymerization of styrene on the silicon surface by ATRP after grafting of the initiator. Several methods of initiator grafting have been used either directly from the hydrogenated surface or indirectly from an acid or ester surface. Styrene has been successfully mass polymerized in a controlled manner on silicon with thicknesses of 9-29 nm of the layer obtained by ellipsometry and Atomic Force Microscopy

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3

Zhang, Weiqiang. "Synthesis of novel chiral pyrrolidine-type (salen)Mn(III) complexes." Thesis, Swansea University, 2006. https://cronfa.swan.ac.uk/Record/cronfa42403.

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The thesis reports the total syntheses of new chiral pyrrolidine-type salen ligands 5.4 and their corresponding Mn(III) complexes 5.5. The salen ligands were synthesized by condensation of tras-(3R,4R)-diaminopyrrolidine (3.12) or trans-(3R,4R)-1-benzyl-3,4-diaminopyrrolidine (3.10) with two equivalents of (R)-3-formyl-2-hydroxy-2'-phenyl-1,1'-binaphthalene [(R)-4.9]. The salen ligands were transformed to their corresponding Mn(III) complexes following a general procedure. The catalytic performances of the synthesized (salen)Mn(III) complexes in asymmetric epoxidation of 1,2-dihydronaphthalene were tested. In chapter 1, a review of asymmetric epoxidation of alkenes is given. Emphasis is placed on the development and some of the important designs of chiral salen ligands and their corresponding (salen)Mn(III) complexes. In chapter 2, the nature of the research project is outlined. In chapter 3, the syntheses of trans-(3R,4R)-diaminopyrrolidine trihydrochloride salt (3.9), trans-(3R,4R)-1-benzyl-3,4-diaminopyrrolidine (3.10) and its trihydrochloride salt (3.11) are reported. These compounds were prepared from (2R,3R)-(-i-)-tartaric acid via multi-step syntheses. Extensive studies on optimization of these transformations are reported. Chapter 4 records the synthesis of (R)-3-formyl-2-hydroxy-2'-phenyl-1,1'-binaphthalene [(R)-4.9] from 2-naphthol via a seven-step synthetic procedure. Extensive studies on these transformations are described, especially on the oxidative coupling of 2-naphthol and on the optical resolution of racemic 2,2'-dihydroxy-1,1'-binaphthalene. In chapter 5, the preparations of salen ligands 5.4 and their corresponding Mn(III) complexes 5.5 are reported. The applications of synthesized Mn(III) complexes in asymmetric epoxidation of 1,2-dihydronaphthalene were carried out. In chapter 6, an overall conclusion of the work is given.

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4

Jones, P. "Studies of chiral metal complexes." Thesis, Bucks New University, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.373593.

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5

Harrison, Stephen Anthony. "Novel chiral cyclopentadienyl metal complexes." Thesis, University of Southampton, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.442873.

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6

Zieleniuk, Candace A. "Anion binding and catalytic studies of metal salen complexes." [Gainesville, Fla.] : University of Florida, 2009. http://purl.fcla.edu/fcla/etd/UFE0024865.

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7

Williamson, Courtney Meghann. "Asymmetric catalysis of cyanide addition reactions using metal(salen) complexes." Thesis, University of Newcastle Upon Tyne, 2011. http://hdl.handle.net/10443/1168.

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Chiral cyanohydrins and α-aminonitriles are versatile intermediates and are of great importance to the pharmaceutical industry due to the ability to convert them into useful chemicals via simple chemical transformations. Chiral cyanohydrins and α-aminonitriles can be obtained from asymmetric cyanohydrin synthesis and asymmetric Strecker reactions respectively. In this project, bimetallic aluminium(salen) complex 1 was studied extensively and was shown to be very active in cyanohydrin synthesis using trimethylsilylcyanide (TMSCN), giving the cyanohydrin trimethylsilyl ether derived from benzaldehyde with 89% (S) enantioselectivity and 80% conversion after 18 hours at -40 oC. A variety of substituted benzaldehydes were screened giving moderate to excellent enantioselectivities. Ketones were also shown to be substrates when used in this catalytic system. Extensive kinetic studies of complex 1 gave the rate equation; rate = k[TMSCN][Ph3PO][1] which is zero order with respect to benzaldehyde. A Hammett study using complex 1 showed that this catalytic system was dominated by Lewis basic catalysis, resulting from the activation of trimethylsilylcyanide by triphenylphosphine oxide. The catalyst was then responsible for the chirality of the product rather than the activation of the aldehyde. A variety of other titanium and vanadium(salen) complexes, containing various substituents on the aromatic ring of the salen ligand were synthesised and screened in the Strecker reaction and cyanohydrin synthesis under different reaction conditions. Enantiomeric excesses of 10-95% (R and S) were achieved with conversions of 10-100% for both reactions.

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8

Achard, Thierry R. J. "Asymmetric catalysis of enolate reactions induced by metal(salen) complexes." Thesis, University of Newcastle Upon Tyne, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.427192.

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9

Bridgewater, Brian Michael. "Sterically hindered chiral transition metal complexes." Thesis, Durham University, 1998. http://etheses.dur.ac.uk/5022/.

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This thesis describes the synthesis, characterization and study of a series of organometallic compounds which all contain the same new ligand, l-phenyl-3-methyl-4,5,6,7-tetrahydroindenyl. The ligand forms a chiral complex once coordinated, and is relatively bulky when compared with ligands such as cyclopentadienyl or 4,5,6,7-tetrahydroindenyl.Chapter one of this thesis introduces cyclopentadienyl ligand chirality, cyclopentadienyl metal complex chirality and sterically demanding cyclopentadienyl systems. The synthesis and chemistry of tetrahydroindenes and some applications of chiral cyclopentadienyl metal complexes and their bulky analogues are also reviewed. Chapter two describes modifications to a literature preparation of the tetrahydroindenone precursor of the new tetrahydroindenyl ligand which lead to higher yields. The synthesis of the ligand itself is described, as well as the synthesis of a benzylidene-substituted hexahydroindene, which demonstrates a limitation in the flexibility of the synthetic route chosen. The synthesis, characterization and various properties of the following iron(II) compounds are discussed in chapter two; bis-l-phenyl-3-methyl- 4,5,6,7-tetrahydroindenyl iron (II), 2.3, l-phenyl-3-methyl-4,5,6,7-tetrahydroindenyl iron(II) dicarbonyl dimer, 2.4, and l-phenyl-3-methyl-4,5,6,7-tetrahydroindaiyl methyl dicarbonyl iron(II), 2.5. For all these iron complexes, the solid state molecular structures and the absolute configuration of the chiral ligand were determined using single crystal X-ray d iffraction. For 23 and 2.4, three isomers are possible, two enantiomers that are collectively termed the rac-isomer and a third isomer, the meso- isomer. Cyclic voltammetric studies on 2.3 indicate that it has a reversible one electron oxidation at 0.187 V (with respect to a non-aqueous Ag/AgCl standard electrode). The difference between this and the reversible one electron oxidation for (η-C(_5)H(_5))(_2)Fe (with respect to the same standard) is -0.314 V, therefore 2.3 is shown to be much more easily oxidized than (η-C(_5)H(_5))(_2)Fe. The solution-state infi-a-red spectrum of 2.4 is explained, with reference to a literature analysis of the unsubstituted analogue [CpFe(CO)(_2)](_2). The steric forces present in the various molecular environments are discussed in connection with the degree of phenyl-ring tilt relative to the cyclopentadienyl mean plane and the deviation of the other cyclopentadimyl substituents away from the metal centre. Subsequent reactions of compounds 2.4 and 2.5 are described. Attempts to make linked analogues of the new ligand are summarized in chapter two. In chapter three, two Zr(rV) compounds are prepared, bis (l-phenyl-3-methyl-4,5,6,7-tetrahydroindenyi) zirconium(fV) dichloride, 3.1, and bis (l-phenyl-3-methyl-4,5,6,7-tetrahydroindenyl) dimethyl zirconium(TV), 3.2. Upon crystallization, rac-3.1 spontaneously resolves into crystals containing only one enantiomer. The similarities and differences in the spectroscopic data for the iron(n) compounds of chapter two and the zirconium(IV) compounds of chapter three are discussed and possible explanations offered . The solid state molecular structures of 3.1 and 3.2 were determined by single crystal X-ray diffraction. Experimental details are given in chapter four, whilst the characterizing data are presented in chapter five. Details of the X-ray structure determinations are given in Appendix A.

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10

Emseis, Paul, University of Western Sydney, of Science Technology and Environment College, and of Science Food and Horticulture School. "Non-classical bonding in chiral metal complexes." THESIS_CSTE_SFH_Emseis_P.xml, 2003. http://handle.uws.edu.au:8081/1959.7/557.

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Intramolecular non-covalent interactions between aromatic ligands in chiral Ru(II) and Co(III) complexes have been investigated in this study. Several investigations were carried out and findings given. The results of the study, which demonstrate the significance of non-covalent interactions involving aromatic residues to the determination of the molecular conformation, serve to highlight the suitability of simple chiral metal complexes to act as models for interactions
Doctor of Philosophy (PhD)

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Emseis, Paul. "Non-classical bonding in chiral metal complexes /." View thesis, 2003. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20031007.121552/index.html.

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Thesis (Ph.D.) -- University of Western Sydney, 2003.
"A thesis submitted as a requirement for admission to the degree of Doctor of Philosophy" Includes bibliographical references (leaves vi, 194-200).

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12

Gathergood, Nicholas Keith Peter. "Chiral cyclopentadienyl lanthanide and transition metal complexes." Thesis, University of Southampton, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.284648.

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13

Chamayou, Anne-Christine [Verfasser], and Christoph [Akademischer Betreuer] Janiak. "Chiral metal-Schiff base complexes = Chirale Metal-Schiff-Base-Komplexe." Freiburg : Universität, 2011. http://d-nb.info/1115490567/34.

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14

Patil, Smita S. "The preparation and use of metal salen complexes derived from cyclobutane diamine." Diss., Kansas State University, 2014. http://hdl.handle.net/2097/18670.

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Doctor of Philosophy
Department of Chemistry
Christopher J. Levy
The helix is an important chiral motif in nature, there is increasing development in field of helical transition metal complexes and related supramolecular structures. Hence, the goals of this work are to apply the principles of helicity in order to produce metal complexes with predictable molecular shapes and to study their properties as asymmetric catalysts. Computational studies suggest that the (1R,2R)-cyclobutyldiamine unit can produce highly twisted salen complexes with a large energy barrier between the M and P helical forms. To test this prediction, the tartrate salt of (1R,2R)-cyclobutyldiamine was synthesized and condensed with a series of saliclaldehydes to produce novel salen ligands. The salicylaldehydes chosen have extended phenanthryl or benz[a]anthryl sidearms to encourage formation of helical coordination complexes. These ligands were metallated with zinc, iron and manganese salts to produce salen metal complexes which were characterized by NMR analysis, high-resolution mass spectrometry, and IR spectroscopy. A second ligand type, neutral bis(pyridine-imine) has also been synthesized from (1R,2R)-cyclobutyldiamine and quinolylaldehydes. The synthesis of bis(pyridine-imine) ligands was conducted using greener method, solvent assisted grinding. These ligands, in-situ with nickel metal salts, showed good catalytic activity for asymmetric Diels-Alder reactions. The third ligand type studied was chiral acid-functionalized Schiff-base ligands. These were synthesized by the condensation of 3-formyl-5-methyl salicylic acid and (1R,2R)-cyclobutyldiamine. With this type of ligand, there is possibility of producing both mono and dinuclear metal complexes. In our studies, we were only able to synthesize mononuclear complexs. These were tested as catalysts for asymmetric direct Mannich-type reaction, but were found to be ineffective.

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15

Dossett, David Michael. "The synthesis of novel chiral transition metal complexes." Thesis, University of Southampton, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.402060.

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16

Niederer-Bátorfi, Melinda [Verfasser]. "Enantioselective ring opening reactions catalysed by heterogenized metal salen complexes / Melinda Niederer-Bátorfi." Aachen : Hochschulbibliothek der Rheinisch-Westfälischen Technischen Hochschule Aachen, 2012. http://d-nb.info/1019762705/34.

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17

Hunt, Jamie. "C1- and C2- Symmetrical Metal-Salen Complexes and their Application to Asymmetric Catalysis." Thesis, University of Newcastle Upon Tyne, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.515075.

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18

Dyers, Leon Jr. "Development of salen metal complexes for the potential catalytic use in asymmetric reaction." DigitalCommons@Robert W. Woodruff Library, Atlanta University Center, 2005. http://digitalcommons.auctr.edu/dissertations/2359.

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This research effort is focused on the development of new transition-metal salencomplexes bearing bulky t-pentyl groups to further understand their role in the directing of substrates to the reactive metal centers. These new chiral and achiral transition-metal salen complexes also possess the ability to be novel asymmetrical catalysts. A series ofsalen ligands were prepared by the condensation of 3,5-di-t-pentyl salicylaldehyde with five different diamines: (1) 1,3-diamino-propan-2-01, (2) benzene-l,2-diamine, (3) ethylene-l,2-diamine, (4) (S,S)-1,2-diamino-l,2-diphenylethane, and (5) 1,2- diaminocyclohexane. These ligands were treated with transition metal salts to give the corresponding transition-metal salen complexes. As a result, five new systems with three crystal x-ray structures were obtained.

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19

Pop, Mihaela Diana. "Symmetrical and asymmetrical Salen-type Schiff-base ligands and their transition metal complexes." Thesis, University College London (University of London), 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.408061.

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20

Ghebregziabiher, Berhe Haile. "Synthesis of chiral thiourea ligands and their transition metal complexes." Thesis, Stellenbosch : Stellenbosch University, 2003. http://hdl.handle.net/10019.1/53610.

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Thesis (MSc)--Stellenbosch University, 2003.
ENGLISH ABSTRACT: Modification of chitosan with benzoylisothiocyanate was attempted, however due to solvent problem the study was left incomplete till appropriate solvent is designed. N,N-diethyl-N -camphanoylthiourea (HL8), N-piperidyl-N '-camphanoylthiourea (HL9), N-pyrrolidyl-N -camphanoylthiourea (HL10) and N,N-diethyl-N -adamantylcarbonyl thiourea (HL11)have been synthesised and characterised for the first time. Two of these ligands HL8 and HL11, were used to form a number of transition metal complexes, namely H30+{fae-[Co(L8-S,Obn, cis-[Ni(L8-S,0)2], trans-[Cu(L8-S,0)2], translcis-[Zn(L 8_S,0)2], translcis-[Pt(L 8_S,0)2], Ag2[(HL8-S)(L-J.1-S,O)]2, translcis- [Ni(L11-S,O)2]and translcis-[Cu(L11_S,O)2]. The new products are fully characterised by means of MS, IR spectroscopy, NMR spectroscopy, elemental (C, H, Nand S) analysis and melting point determinations. The H30+{fae-[Co(L8-S,Obn, cis-[Ni(L8- S,O)2], trans-[Cu(L8-S,O)2] and Ag2[(HL8-S)(L-J.1-S,O)]2 are also characterised by Xray diffraction analysis. The structure of the new chiral N,N-dialkyl-N' -camphanoylthiourea ligand (HL8) has a significant effect on its coordination chemistry with transition metal ions. This ligand forms H30+ {fae-[Co(L8-S,Obn, cis-[Ni(L8-S,0)2], trans-[Cu(L-S,O)2] and Ag2[(HL8- S)(L8-J.1-S,O)]2 complexes with the Co(II), Ni(II), Cu(II) and Ag(I) metal ions respectively. The spectroscopic and X-ray diffraction results of these complexes indicate a bidentate mode of coordination of the ligand (with its Sand °donor atoms) to the Co(II), Ni(II) and Cu(II) metal ions. The reaction of this ligand with silver(I) however affords the formation of a binuclear silver(I) complex exhibiting monodentate and bidentate modes of coordination within the same complex. The exclusive formation of trans-[Cu(L8-S,0)2] is a new phenomenon for the HL type thiourea ligands with Sand °donor atoms. Up to this point a maximum of 15 % trans-isomer has been reported in ltterature." All the transition metal complexes made with HL8and HL11are air stable in both the liquid and solid states except the H30+{fae-[Co(L 8-S,Ob]} Interestingly the deep green fae- H30+{fae-[Co(L8-S,Obn complex is air sensitive and the Co(II) oxidizes to Co(III) in the complex by atmospheric O2. The oxidation of Co(II) to Co(III) in the complex is confirmed by 1Hand 13CNMR spectra as well as by UV-Visible spectra of the complex. The NMR spectra of the complexes indicated the presence of one isomer in each complex except for the NMR spectra of the platinum complex of the HL8 ligand. The presence of the minor trans-[Pt(L8-S,Q)21 isomer in combination with the major cis-[Pt(L8-S,Q)21 isomer in the platinum complex was indicated by the 1H, 13Cand 195ptNMR spectra of the complex.
AFRIKAANSE OPSOMMING: Pogings om chitosan met benzoylisothiocyanate te modifiseer is onvoltooid gelaat weens die gebrek aan'n geskikte oplosmiddel. N,N-diethyl-N -carnphanoylthiourea (HL8), N-piperidyl-N -camphanoylthiourea (HL9), N-pyrrolidyl-N -camphanoylthlourea (HL10) en N,N-diethyl-N -adamantylcarbonyl thiourea (HL11) is vir die eerste keer gesintetiseer en gekarakteriseer. Twee van die ligande, HL8 en HL11, is gebruik om verskeie oorgangsmetaalkomplekse te berei, nl. H30+{fac-[Co(L8-S,Ohn, cis-[Ni(L8-S,0)2], trans-[Cu(L8-S,0)2], trans/cis-[Zn(L8 - S,0)2], trans/cis-[Pt(L8-S,0)2], Ag2[(HLB-S)(L-jl-S,0)]2, trans/cis-[Ni(L11-S,0)2] en trans/cis-[Cu(L11_S,0)2]. Die nuwe produkte is volledig gekarakteriseer deur middel van MS, IR spektroskopie, KMR spektrometrie, elemente (C, H, N en S) analise en smeltpuntbepaling. Die komplekse H30+{fao-[Co(L8-S,0)3n, cis-[Ni(L8-S,0)2], trans- [Cu(L8-S,0)2] en Ag2[(HLB-S)(L-jl-S,0)]2 is ook deur middel van X-straaldiffraksieanalise gekarakteriseer. Die struktuur van die nuwe chirale N,N-dialkyl-N'-camphanoylthiourea ligand (HL8) het In beduidende invloed op die koordinasie van hierdie ligand met oorgangsmetaalione. Die ligand vorm H30+{fac-[Co(L8-S,Ohn, cis-[Ni(L8-S,0)2], trans-[Cu(L-S,0)2] en Ag2[(HL8-S)(L8-Il-S,0)]2 komplekse met Co(ll)-, Ni(II)-, Cu(II)- en Ag(I)-ione respektiewelik. Spektroskopiese en X-straaldiffraksie-analise van die komplekse toon dat die ligande op 'n bidentate wyse d.m.v. die S- en O-donoratome met Co(II), Ni(lI) en Cu(lI) koordineer. Die reaksie van hierdie ligand met Ag(I)-ione lei egter tot die vorming van 'n dikernige silwer(I)-kompleks waarin die ligande monodentaat (S) en bidentaat (S en 0) aan die metaal gebind is. Die vorming van uitsluitlik die trans-[Cu(L8-S,0)2] in die reaksie van HL8 met Cu(lI) is 'n besondere fenomeen in die chemie van hierdie tipe ligande; in die literatuur word melding gemaak van slegs een ander trans-kompleks met hierdie ligande, en dan wel met 'n maksimum opbrengs van 15%.29 Alle oorgangsmetaalkomplekse met HLB en HL11 is stabiel indien blootgestel aan lug, ongeag of die verbindings opgelos word of in die vastetoestand verkeer, behalwe H30+{fao-[Co(L8-S,Ohn. Die diep-groen gekleurde H30+{fao-[Co(L8-S,Ohn)3]} kompleks is lugsensitief; Co(lI) word deur lugsuurstof na Co(lIl) ge-oksideer. Die oksidasie in die kompleks kan deur middel van 1H en 13CKMR spektrometrie sowel as UV-sigbare spektrofotometrie bevestig word. Die KMR spektra van alle komplekse dui op die teenwoordigheid van slegs een isomeer in oplossing, behalwe in die geval van die platinum(lI) kompleks met HL8. Die teenwoordigheid van lae konsentrasies trans-[Pt(L8-S,0)2] isomeer tesame met veel hoër konsentrasies van die cis-[Pt(L8 -S,O)2] isomeer word deur 1H, 13Cen 195ptKMR spektroskopie aangedui.

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21

Green, Simon Michael. "The synthesis and application of novel chiral transition metal complexes." Thesis, University of Southampton, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285879.

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22

Barman, Sanmitra. "Helical transition metal complexes as catalysts for asymmetric sulfoxidations and aldol addition reactions." Diss., Kansas State University, 2010. http://hdl.handle.net/2097/7015.

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Doctor of Philosophy
Department of Chemistry
Christopher J. Levy
Stepped helical salen complexes with vanadium as the central metal were synthesized and characterized. The helicity in these complexes arise from the fused phenyl rings (phenanthryl and benz[a]anthryl) as sidearms, whereas the chirality arises from the chiral cyclohexyl diamine or binaphthyl diamine backbones. These complexes showed good yields and moderate enantioselectivity in asymmetric sulfoxidation reactions with methylphenyl sulfide as the substrate and H2O2 or cumene hydroperoxide as the oxidants. To further improve the closed nature of these complexes with a tetradentate salen ligand, we synthesized and characterized vanadium complexes with tridentate (S)-NOBIN backbone Schiff base ligands with phenanthryl and benz[a]anthryl as the sidearms. After initial catalytic study, we concluded that these catalysts are too open in nature to impose face selection during asymmetric induction. We also synthesized and characterized vanadium and titanium salan complexes. These complexes can adopt β-cis geometry, thereby making the complex “chiral at metal” and they are known for better catalysts in terms of asymmetric induction than their unreduced counterparts. However, these complexes showed better catalytic activity than their unreduced counterparts in sulfoxidation reactions with methylphenyl sulfide as the substrate and H2O2 or cumene hydroperoxide as the oxidants. We also put an effort to synthesize mixed salen complexes with vanadium as the central metal. These complexes have two different sidearms attached to one backbone unit. However, our method did not work well to produce pure mixed salen ligands. The catalysis results for mixed salen vanadium complexes are also comparable to the unreduced vanadyl salen complexes. Lastly, we synthesized and characterized new helical titanium Schiff base complexes with (S)-NOBIN backbone and phenanthryl and benz[a]anthryl sidearms. Single crystal studies showed that these complexes exist in the M helical conformation in the solid state. These complexes showed moderate activity in asymmetric aldol addition reactions between 2-methoxy propene and different aldehydes.

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23

Nimmagadda, Sri Krishna. "Asymmetric Transformations Catalyzed By Chiral BINOL Alkaline Earth Metal Phosphate Complexes." Scholar Commons, 2016. http://scholarcommons.usf.edu/etd/6554.

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Small molecule hydrogen bond donors have emerged as versatile catalysts in asymmetric synthesis. Within this class, chiral BINOL phosphoric acid is regarded as one of the pioneer catalysts used in several asymmetric transformations. The ability of the catalyst to activate the substrates could be controlled in two different ways. (1) Dual activation/bifunctional activation of substrate by hydrogen bond interactions or ion pairing with phosphoric acid or (2) By forming chiral BINOL phosphate metal complex that could significantly alter the interactions in chiral space. In particular, chiral alkaline earth metal phosphate complexes have unique advantages as catalysts owing to the ubiquitous availability of alkaline earth metals, strong Brønsted basicity of their counterions, mild but significant Lewis acidity of the metal and their ability to coordinate at multiple reactive sites due to large ionic radius. Chapter 1 summarizes the recent development of alkaline earth metal complexes in asymmetric catalysis. My thesis dissertation is focused on the application of chiral alkaline earth metal phosphate complexes in novel asymmetric reactions. In Chapter 2, we disclosed an efficient asymmetric one-pot synthesis of chiral 1,3-oxazolidines and chiral 1,3-oxazinanes. Chiral oxazolidines and oxazinanes are widely used as auxiliaries in asymmetric transition metal catalysis and also key structural motifs in natural products with biological activities. We developed a new synthetic method for chiral 1,3-oxazolidines which follows the enantioselective addition of alcohols to imines catalyzed by chiral 3,3’-(triisopropylphenyl)-derived BINOL magnesium phosphate to form hemiaminal intermediate, which then undergoes mild base mediated intramolecular nucleophilic substitution to afford highly enantioselective 1,3-oxazolidines and 1,3-oxazinanes in good yields. In Chapter 3, we developed the first catalytic enantioselective desymmetrization process for the synthesis of novel axially chiral cyclohexylidene oxime ethers. Even though these molecules were found to be optically active in 1910, methods to synthesize these molecules are scarce. We have developed an efficient desymmetrization process of 4-phenyl cyclohexanones with phenoxyamines catalyzed by chiral BINOL strontium phosphate complex to afford highly enantioselective products. We then extended this methodology to the dynamic kinetic resolution of 2-substituted cyclohexanones to form chiral 2-substituted cyclohexyl oximes in good enantioselectivities, as demonstrated in Chapter 4. We further demonstrated the utility of these compounds by converting them to chiral 2-aryl cyclohexylamines which are important synthetic intermediates.

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24

Choi, So-Young Amy. "Synthesis, properties, and asymmetric catalysis of chiral cyclophanes and their metal complexes." Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2006. http://wwwlib.umi.com/cr/ucsd/fullcit?p3206584.

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Thesis (Ph. D.)--University of California, San Diego, 2006.
Title from first page of PDF file (viewed May 10, 2006). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references (p. 244-263).

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25

Gahagan, Michael P. "Applications of some chiral #beta#-ketophosphonate transition metal complexes in epoxidation catalysis." Thesis, University of St Andrews, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.238547.

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26

Long, James Maurice. "Synthesis of new axially chiral diphosphines and phosphinamines for asymmetric catalysis." Thesis, University of Oxford, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337600.

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27

Gray, Mary Jo. "The synthesis and properties of several aluminophophates templated by chiral transition metal complexes." Thesis, Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/30490.

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28

McCormack, Peter J. "An investigation of the synthesis, characterisation and applications of some chiral metal complexes." Thesis, University of Warwick, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.343827.

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29

Clarke, Catherine Ann. "The synthesis and characterisation of transition metal complexes of some novel chiral multidentate ligands." Thesis, Heriot-Watt University, 1998. http://hdl.handle.net/10399/1111.

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30

Brookings, Daniel Christopher. "The design, synthesis and application to asymmetric catalysis of chiral transition metal cyclopentadienyl complexes." Thesis, University of Southampton, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.273849.

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31

Wingstrand, Erica. "New Methods for Chiral Cyanohydrin Synthesis." Doctoral thesis, KTH, Kemi, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-10205.

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This thesis deals with method development in asymmetric catalysis and specifically syntheses of enantioenriched O-functionalized cyanohydrins. The first part describes the development of a method for the synthesis of O‑alkoxycarbonylated and O-acylated cyanohydrins. Ethyl cyanoformate and acyl cyanides were added to aldehydes in a reaction catalyzed by a chiral dimeric Ti-salen complex together with a tertiary amine. High yields and enantioselectivities were in most cases obtained. Mechanistic studies were performed and a reaction mechanism was proposed. The second part describes a method in which the undesired minor enantiomer in a Lewis acid–Lewis base-catalyzed acylcyanation is continuously recycled into prochiral starting material. Close to enantiopure O‑acylated cyanohydrins were obtained in high yields. The third part deals with asymmetric acylcyanations of ketones. Acetyl cyanide was found to add to α‑ketoesters in a reaction catalyzed by a chiral Lewis base. Yields up to 77% and 82% ee were obtained. The final part describes an enzymatic method for high-throughput analysis of O‑acylated cyanohydrins. The enantiomeric excess and conversion were determined for products obtained from a number of aromatic and aliphatic aldehydes.
QC 20100818

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32

Petherick, Janice, University of Western Sydney, and School of Science. "Chiral discrimination associated with complex molecules." THESIS_XXXX_SS_Petherick_B.xml, 1999. http://handle.uws.edu.au:8081/1959.7/134.

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This thesis is a report on the design, synthesis and molecular structure of a set of chiral Co(III) metal complexes, in the solution and solid state. The complexes that have been synthesised will potentially intercalate between the base pairs of DNA. The structure of the bound tetradentate ligand, S,S-picchxnMe2 in the solid state was investigated to determine the flexibility of this seemingly rigid ligand. The bidentate ligands, R- and S-glu, were also bound to the Co complex and the differences in the tetradentate ligand were observed. The differences observed in the bonded tetradentate ligands were due to the chirality of the bonded amino acid. The aromatic amino acids, R- and S-phe, were used as bidentate ligands because of their ability to intercalate with DNA. Several scientific experiments were conducted and the results analysed in great depth
Doctor of Philosophy (PhD)

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33

周向葛 and Xiangge Zhou. "Asymmetric reactions catalyzed by transition metal complexes containing binaphthyl schiff bases and chiral porphyrinato ligands." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1999. http://hub.hku.hk/bib/B31239833.

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Zhou, Xiangge. "Asymmetric reactions catalyzed by transition metal complexes containing binaphthyl schiff bases and chiral porphyrinato ligands /." Hong Kong : University of Hong Kong, 1999. http://sunzi.lib.hku.hk/hkuto/record.jsp?B21021363.

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35

Ma, Liqing. "Synthesis and Characterization of Ligands and Transition Metal Complexes Containing M-Terphenyl Scaffolds." Case Western Reserve University School of Graduate Studies / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=case1162925165.

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36

Billodeaux, Damon Ray. "Investigations on the use of main group metal complexes of salen ligands as catalysts for the copolymerization of CO2 and epoxides." Texas A&M University, 2005. http://hdl.handle.net/1969.1/2425.

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Current industrial processes for the production of polycarbonates, a thermoplastic valued for commercial applications, leave much to be desired from an environmental viewpoint. Research into alternative methods for production of polycarbonates has focused on the copolymerization of carbon dioxide and epoxides for the benefits of eliminating phosgene as a reagent, and for the economic impact of incorporating CO2 as a low cost C1 feedstock. Early work in this field focused on the use of zinc-derived catalysts, but recent studies indicate that chromium complexes of the salen (N,N-bis-(salicylidene)-1,2-ethylene diimine) family of ligands are far superior to the zinc complexes in terms of reactivity and diminishing the formation of unwanted byproducts. Concomitant to the studies of chromium salen complexes, investigations of main-group salen metal complexes were carried out. Aluminum complexes were able to produce polycarbonate in the presence of tetrabutyl ammonium salts and neutral Lewis bases. Gallium complexes were essentially inactive for generating any product. Tin(IV) complexes were active for the production of polyether, the result of homopolymerization of epoxide without CO2 insertion. Tin(II) complexes generated the monomeric cyclic carbonate product but no copolymer. An additional aspect of research relative to this field of study is the development of polymeric materials from several different epoxide monomers. The complex [hydrotris(3-phenyl-pyrazol-1-yl)borate]Cd(II) acetate was used to study the thermodynamics of the binding of a series of potential epoxide monomers to a metal center via 113Cd NMR. Activation of the epoxide by a metal center was found to not play a significant role in the ability of the complex to be subsequently ring-opened for polymerization. A final relevant area of study involved the synthesis of cadmium analogues of Fe/Zn double metal cyanide (DMC) complexes. Heterogeneous DMCs are well known in patent literature as excellent catalysts for the production of polycarbonates and cyclic carbonates from CO2 and epoxides. Previous studies on homogeneous Fe/Zn DMCs have only provided cyclic carbonate. Cd analogues of these species provide a convenient NMR handle for studies on the activity of the metal centers in presence of an epoxide and by changes to the DMC structure.

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37

Frantz, Eric Benjamin. "Synthesis, reactivity, and coordination chemistry relevant to the copolymerization of CO2 and epoxides by first row transition metal schiff base complexes." [College Station, Tex. : Texas A&M University, 2008. http://hdl.handle.net/1969.1/ETD-TAMU-2893.

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38

何國強 and Kwok-keung Paul Ho. "Molecular structures and physicochemical properties of some chiral andhelical transition metal complexes with polypyridines and tetradentateanionic ligands." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1996. http://hub.hku.hk/bib/B31234884.

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39

Ibragimov, Sergey. "A molecular loop with interstitial channels in a chiral environment and study of formation of metal-metal bonds in dinickel, dipalladium and dititanium complexes." Texas A&M University, 2005. http://hdl.handle.net/1969.1/3760.

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This dissertation consists of two independent topics: (1) a molecular loop with interstitial channels in a chiral environment; (2) study of formation of metal-metal bonds in dinickel, dipalladium and dititanium complexes On the first topic, a study of the reaction products of the interaction of cis- Mo2(DAniF)2(CH3CN)4 2+ corner pieces with ortho-, meta- and para- isomers of enatiomerically pure ÂO2CCH(CH3)C6H4CH(CH3)CO2 Â dicarboxylate was performed. First, an enantiomerically pure molecular loop based on two dimolybdenum units and two para-dic arboxylate linkers was synthesized and structurally characterized. Similar reactions with isomeric ortho- and meta- dicarboxylate linkers, as well as with some nonchiral ligands, showed that the structure of the obtained products depends on the geometry of the ligand. Meta- dicarboxylate linker favors the formation of the chelated product and ortho- dicarboxylate linker produces the mixture of chelated molecules and loops. On the second topic, an investigation of the formation of metal-metal bonds was performed. Study of the one-electron bond obtained upon oxidation of Ni2 4+ and Pd2 4+ to Ni2 5+ and Pd2 5+, respectively, was made. The compounds synthesized were studied with various physical methods, such as X-ray crystallography, UV-visible spectroscopy and EPR spectroscopy. The nature of oxidized species as well as the dependence of metalmetal interactions on electron-donating abilities of bridging ligands was studied. It was shown that oxidation takes place on a metal center. The formation of one-electron bond in oxidized species is proposed. Finally formation of Ti2 6+ single bonded compounds by the reduction of two Ti4+ monomers to Ti2 6+ dimer was studied. The nature of the species obtained in solution and in solid state is discussed. The crystal structure shows the presence of two types of hpp ligands Â chelating and bridging. NMR study of this compound in solution proposes the rearrangement of this structure to a paddlewheel.

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40

Shen, Xiaodong [Verfasser], and Eric [Akademischer Betreuer] Meggers. "Octahedral Chiral-at-Metal Iridium and Rhodium Complexes as Versatile Asymmetric Catalysts / Xiaodong Shen. Betreuer: Eric Meggers." Marburg : Philipps-Universität Marburg, 2016. http://d-nb.info/1102354457/34.

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41

何振華 and Chun-wah Ho. "Study on osmium and manganese complexes of chiral binaphthylic tetradentate ligands and their application to asymmetric epoxidationof alkenes." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1994. http://hub.hku.hk/bib/B31233570.

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Ho, Chun-wah. "Study on osmium and manganese complexes of chiral binaphthylic tetradentate ligands and their application to asymmetric epoxidation of alkenes /." [Hong Kong : University of Hong Kong], 1994. http://sunzi.lib.hku.hk/hkuto/record.jsp?B13787020.

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43

Qin, Jie [Verfasser], and Eric [Akademischer Betreuer] Meggers. "New Catalytic Properties of Chiral-at-Metal Complexes and a Cyclometalated Ru Complex / Jie Qin ; Betreuer: Eric Meggers." Marburg : Philipps-Universität Marburg, 2021. http://d-nb.info/1236691997/34.

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44

Ho, Kwok-keung Paul. "Molecular structures and physicochemical properties of some chiral and helical transition metal complexes with polypyridines and tetradentate anionic ligands /." Hong Kong : University of Hong Kong, 1996. http://sunzi.lib.hku.hk/hkuto/record.jsp?B17545675.

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45

Sau, Yiu Keung. "Part I, Synthesis and reactivity of 2,2'-bipyridine-supported iridium alkyl compounds ; Part II, Metal complexes with chiral phosphine oxide and sulfoxide ligands /." View abstract or full-text, 2005. http://library.ust.hk/cgi/db/thesis.pl?CHEM%202005%20SAU.

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46

Huo, Haohua [Verfasser], and Eric [Akademischer Betreuer] Meggers. "Asymmetric Catalysis with Chiral-at-Metal Complexes: From Non-Photochemical Applications to Photoredox Catalysis / Haohua Huo. Betreuer: Eric Meggers." Marburg : Philipps-Universität Marburg, 2016. http://d-nb.info/1108765890/34.

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47

Ferro, Lorenzo. "I. Group 14 metal alkoxides : synthesis and reactivity studies II. Synthesis of novel planar chiral complexes based on [2.2]paracyclophane." Thesis, University of Sussex, 2011. http://sro.sussex.ac.uk/id/eprint/7448/.

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I. A series of group 14 β-diketiminate alkoxides (BDI)EOR (BDI = [CH{(CH3)CN-‐2,6-‐iPr2C6H3}2; E = Ge, Sn, Pb; R = iPr, sBu, tBu) was synthesised and characterised. The reactivity towards aliphatic and unsaturated electrophiles was investigated. For the tin and lead systems, an unexpected trend was observed. For instance, they do not or very sluggishly react with aliphatic electrophiles, but readily activate carbon dioxide. The slower tin system was used to investigate the mechanism of carbon dioxide insertion through detailed kinetic, thermodynamic and DFT studies. The isostructural germanium system showed a different reactivity pattern. Treatment with aliphatic electrophiles and iodine leads to cationic Ge(IV) oxidative addition products, whereas reactivity towards heterocumulenes was not observed. The Lewis basic behaviour was also investigated, revealing that the germanium lone pair coordinates to copper(I) iodide. The synthesis of an isostructural mercury system was also attempted, resulting in the formation of the first homoleptic bis‐β‐diketiminate complex bound through the γ‐carbons. II. Monosubstituted paracyclophane was exploited in the synthesis of a novel β‐diketimine and enaminone both possessing planar chirality. These were used to stabilise N,N'- and N,O-chelated scandium and zirconium complexes, potentially suitable for asymmetric hydroamination catalysis. Preliminary tests show nocatalytic activity.

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48

Dyson, Gavin. "Synthesis of amine functionalised di-N-heterocyclic carbenes and chiral N-heterocyclic carbene-Schiff base transition metal complexes and their application to homogeneous catalysis." Thesis, University of York, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.440968.

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49

Wagner, Alec T. "Design and Synthesis of Mixed-Metal Supramolecular Complexes Incorporating Specialized Light Absorbing Units to Investigate Processes Relevant to Catalyst Function." Diss., Virginia Tech, 2015. http://hdl.handle.net/10919/73572.

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The goal of this research was to develop a series of mixed-metal supramolecular complexes with specialized light absorbing units to probe perturbation of excited-state properties by ligand deuteration and long-term complex stability via racemization of initially enantiopure light absorbing subunits. Varying bidentate polypyridyl terminal ligands (TL), bridging ligands (BL), reactive metal center (RM), or number of Ru(II) light absorbers (LA) tunes the electrochemical, spectroscopic, photophysical, and photochemical properties within the supramolecular architecture. Ru(II) monometallics of the design [(bpy)2Ru(prolinate)](PF6) utilize prolinate as a chiral directing ligand to impart chirality to the Ru(II) LAs in the synthesis of more sophisticated supramolecular complexes. Ru(II) monometallics of the design [(TL)2Ru(BL)](PF6)2 (TL = bpy or d8-bpy; BL = dpp or d10-dpp; bpy = 2,2′-bipyridine; dpp = 2,3-bis(2-pyridyl)pyrazine) covalently couple two TLs and one BL to a central Ru(II) metal center forming a LA subunit. Larger bi- and trimetallic complexes are formed by coupling an additional Ru(II), Rh(III), or Pt(II) metal center to an existing Ru(II) LA through a BL. Ru(II),Ru(II), Ru(II),Rh(III), and Ru(II),Pt(II) bimetallics of the design [(TL)2Ru(BL)Ru(TL)2](PF6)4, [(TL)2Ru(BL)RhCl2(TL′)](PF6)3, and [(TL)2Ru(BL)PtCl2](PF6)2 (TL/TL′ = bpy or d8-bpy; BL = dpp or d10-dpp) couple only one Ru(II) LA to a Ru(II), Rh(III), or Pt(II) metal center through the BL. Ru(II),Rh(III),Ru(II) trimetallics of the design [{(TL)2Ru(BL)}2RhCl2](PF6)5 (TL = bpy or d8-bpy; BL = dpp or d10-dpp) covalently couple two Ru(II) LAs to a central Rh(III) RM through polyazine BLs. The complexes discussed herein are synthesized using a building block approach, permitting modification of the supramolecular architecture through multiple synthetic steps. Electrochemical analysis of the mono-, bi-, and trimetallic complexes displays several common features: a Ru-based HOMO and either a bridging ligand or Rh-based LUMO. TL and BL modification by ligand deuteration does not affect the electrochemistry of the Ru(II), Ru(II),Ru(II), Ru(II),Rh(III), or Ru(II),Rh(III),Ru(II) complexes. Likewise, utilizing a single enantiomer of the LA subunit does not modify the redox behavior of Ru(II), Ru(II),Pt(II), or Ru(II),Rh(III),Ru(II) complexes. All of the mono-, bi-, and trimetallic complexes are efficient light absorbers throughout the UV and visible with π→π* intraligand (IL) transitions in the UV and Ru(dπ)→ligand(π*) metal-to-ligand charge transfer (MLCT) transitions in the visible. Ligand deuteration does not affect the light absorbing properties of the complexes, while incorporation of chiral LA subunits imparts a preference for circularly polarized light (CPL) absorbance into supramolecular complexes. Photoexcitation of the Ru(dπ)→dpp(π*) 1MLCT results in near unity population of short-lived, weakly emissive Ru(dπ)→dpp(π*) ³MLCT excited state. In the Ru(II), Ru(II),Ru(II), and Ru(II),Pt(II) complexes, the 3MLCT excited state relaxes to the ground state by emission of a photon or vibrational relaxation processes. In the Ru(II),Rh(III) and Ru(II),Rh(III),Ru(II) complexes, the 3MLCT excited state is efficiently quenched by intramolecular electron transfer to populate a non-emissive Ru(dπ)→'Rh(dσ*) metal-to-metal charge transfer (3MMCT) excited state. Utilizing a deuterated BL, the excited-state lifetimes and quantum yield of emission (Φem) are increased for Ru(II), Ru(II),Ru(II), Ru(II),Rh(III) and Ru(II),Rh(III),Ru(II) complexes. The Ru(II),Rh(III) and Ru(II),Rh(III),Ru(II) complexes have previously been shown to be exceptional photochemical molecular devices (PMD) for photoinitiated electron collection (PEC). The ability of these complexes to undergo multiple redox cycles, efficiently absorb light, populate reactive excited states, and collect electrons at a reactive Rh metal center fulfills the requirements for H2O reduction photocatalysts. Photolysis of the Ru(II),Rh(III) and Ru(II),Rh(III),Ru(II) complexes with 470 nm light in the presence of a sacrificial electron donor and H2O substrate yields photocatalytic H2 production. Varying the BL from dpp to d10-dpp in the bimetallic architecture results in enhanced, although relatively low, catalyst efficiency producing 40 ± 10 μL H2 with dpp and 80 ± 10 μL H2 with d10-dpp in a CH3CN solvent system after 48 h photolysis. The trimetallic architecture showed no enhancement in photocatalytic efficiency and produced 210 ± 20 μL H2 with dpp and 180 ± 20 μL H2 with d10-dpp in a DMF solvent system after 20 h photolysis. The Ru(II),Rh(III) and Ru(II),Rh(III),Ru(II) complexes' behavior differs in that the excited state lifetime is the most important factor for bimetallic catalyst functioning, but intramolecular electron transfer is the most important factor for the trimetallic photocatalysts. Another important property to understand with these catalysts is their long-term stability in solution. In order for these mixed-metal complexes to be industrially useful, they must perform for long periods of time without degradation in the presence of H2O substrate and electron donors in solution. Previous examinations of Ru(II),Rh(III),Ru(II) photocatalysts have found that they can perform for ca. 50 h of photolysis, but are not as effective as the initial few hours. Special care was taken to synthesize enantiopure LA subunits and incorporate them into Ru(II),Pt(II) and Ru(II),Rh(III),Ru(II) architectures to study their photolytic stability by monitoring how long the complexes retained their chirality using electronic circular dichroism (ECD) spectroscopy. After photolyzing for longer than 200 hours with an LED light source, the quantum yield for racemization (Φrac) for the Ru(II),Pt(II) and Ru(II),Rh(III),Ru(II) architectures is 2.6 ⨉ 10⁻⁸ and 0.72 ⨉ 10⁻⁸ respectively. Also, by photolyzing in the presence of free bpy, the bi- and trimetallic complexes racemize via a non-dissociative trigonal twist mechanism. This dissertation reports the detailed analysis of the electrochemical, spectroscopic, photophysical, and photochemical properties of a series of selectively deuterated [(TL)2Ru(BL)](PF6)2, [(TL)2Ru(BL)Ru(TL)2](PF6)4, [(TL)2Ru(BL)RhCl2(TL′)](PF6)3, and [{(TL)2Ru(BL)}2RhCl2](PF6)5 (TL = bpy or d8-bpy; BL = dpp or d10-dpp; bpy = 2,2′-bipyridine; dpp = 2,3-bis(2-pyridyl)pyrazine) supramolecular complexes and a series of [(bpy)2Ru(prolinate)](PF6), [(bpy)2Ru(dpp)](PF6)2, [(bpy)2Ru(dpp)PtCl2](PF6)2, and [{(bpy)2Ru(dpp)}2RhCl2](PF6)5 supramolecular complexes with enantiopure light absorbing subunits. The design of the supramolecular architecture and intrinsic properties of each subunit contribute to the function of these systems. The careful design, synthesis and purification, thorough characterizations, and experimentation have led to deeper understanding of the molecular properties required for efficient H2O reduction.
Ph. D.

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50

Weeks, Jennifer Megan. "A structural thermodynamic and equilibrium study of chiral pendant arm triaza macrocyclic ligand complexes: towards the formation of metal-ion activated molecular receptors : a thesis submitted for the degree of Doctor of Philosophy at the University of Adelaide (Faculty of Science) /." Title page, table of contents and abstract only, 2000. http://web4.library.adelaide.edu.au/theses/09PH/09phw395.pdf.

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Dissertations / Theses on the topic 'Chiral metal salen complexes'

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