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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Synthesis and characterisation of oxorhenium(V) and tricarbonylrhenium(I) complexes with biologically active N, O and N, S-Donor ligands

Mukiza, Janvier January 2013 (has links)
This study investigated the synthesis of rhenium(I) and rhenium(V) complexes with a variety of multidentate NS, NSO, NO and SO-donor ligands. It also investigated the synthesis of dinuclear dihalogeno- and trihalogeno-bridged rhenium(I) complexes based on the fac-[Re(CO)3]+ core. The reactions of hydrated folic acid with [Re(CO)5X] (X = Cl, Br) were studied, and the complexes [Re(CO)3(H2O)3]+[Re2(μ-X)3CO)6]−.5H2O [X= Br (1), Cl(2)] were isolated. The reaction of orotic acid potassium salt [Re(CO)5Br] was performed, and the complex [Re2(μ-Br)2(CO)8] was isolated. The reaction of bis(piperidin-1- yl)methanone with [Re(CO)5Cl] followed by recrystallisation of the resulting precipitate in dichloromethane/acetontrile resulted in the complex [Re2(μ- Cl)2(CO)6(MeCN)2]. The X-ray crystal structures show that all these complexes display a distorted octahedral geometry around the central rhenium atoms. The reactions of aroylhydrazone-based ligands such as 3-((pyridin- 2yl)methyleneamino)-2,3-dihydro-2-pyridin-2yl)quinazolin-4-(1H)-one (Hppq) and N-(di(pyridin-2-yl)methylene)benzohydrazide (Hdpmb) with [Re(CO)5Cl] were studied and led to the formation of the complexes [Re(CO)3Cl(Hdpmb)] and [Re(CO)3Cl(Hppq)]. The Hdpmb and Hppq coordinated to the fac-[Re(CO)3]+ core as neutral bidentate chalates via the pyridinic nitrogens (for Hdpmb) and via imino and pyridinic nitrogens for Hppq. The X-ray crystal structures show that the geometry around the rhenium in both complexes is a distorted octahedral. The treatment of the dithizone (H2dz) ligand with rhenium(V) precursors containing a triphenylphosphine group (PPh3) led to the decomposition of dithizone. The decomposition product reacted with the triphenylphosphine group and generated a new ligand triphenylphosphazeno-N-phenylmethanethiohydrazide (H2L). The reaction of trans-[ReOX3(PPh3)2] (X = Cl, Br) with dithizone (H2dz) led to the complex [ReO(dz)2][ReO(HL)2]. The reaction of trans-[ReOI2(OEt)(PPh3)2] with H2dz led to the same product. The reaction of cis-[ReO2I(PPh3)2] with H2dz in methanol led to [ReO(dz)2][ReO(HL)2](MeOH)2 in which methanol bonded to HLvia hydrogen bonds. The H2dz was doubly deprotonated and coordinated to the [ReO]3+ moiety via a thiolate sulfur and deprotonated hydrazinic nitrogen to yield [ReO(dz)2]−, while the H2L was singly deprotonated and coordinated to [ReO]3+ moiety via the neutral sulfur atom and deprotonated hydrazinic nitrogen to yield [ReO(HL)2]+. The X-ray crystal structure show that in both [ReO(HL)2]+ and [ReO(dz)2]−, the rhenium atoms are five-coordinated and adopt a distorted squarebased pyramidal geometry. The reaction of thiosemicarbazones such as salcylidene-4- phenylthiosemicarbazide (H3salpt) with cis-[ReO2I(PPh3)2] was investigated and led to the complex [ReO(Hsalpt)(H2salpt)]. The X-ray study reveals that Hsalpt is present as a tridentate chelate coordinating via the thiolate sulfur, imino nitrogen and phenolic oxygen, while H2salpt coordinates as a bidentate chelate via the thiolate sulfur and imino nitrogen atoms. The geometry around rhenium is distorted octahedral. The coordination mode of the benzoylthiourea derivatives 4-tert-butyl-N- (diphenylcarbamothioyl)benzamide (Htpb) and N-(diethylcarbamothioyl)benzamide (Heb) to the [Re2O3]4+ and fac-[Re(CO)3]+ cores were investigated. The reaction of [Re(CO)5Cl] in presence of sodium acetate with Htpb led to the dimeric complex [Re(CO)3(tpb)]2 in which the tpb coordinated to the fac-[Re(CO)3]+ core via the ketonic oxygen and bridging thiolate sulfur. The same reaction with Heb led to the monomeric complex [Re(CO)3(eb)(Heb)], in which the eb coordinates to the fac-[Re(CO)3]+core via thiolate sulfur and ketonic oxygen with Heb binding via the neutral sulfur atom. The reaction of Heb with cis-[ReO2I(PPh3)2] at room temperature with excess of sodium acetate led to the dimeric complex (μ-O)[ReO(eb)2]2 in which Heb is present as a monoanionic (deprotonated) bidentate with coordination through the thiolate sulfur and ketonic oxygen.
12

Experimental studies in the isomerism and structural variations in molybdenum and rhenium halo-compounds

Anderson, Ian Robert. January 1968 (has links) (PDF)
Includes bibliography.
13

Experimental studies in the isomerism and structural variations in molybdenum and rhenium halo-compounds / Ian Robert Anderson.

Anderson, Ian Robert January 1968 (has links)
Includes bibliography. / 111 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Physical and Inorganic Chemistry, 1968
14

Experimental studies in the isomerism and structural variations in molybdenum and rhenium halo-compounds /

Anderson, Ian Robert. January 1968 (has links) (PDF)
Thesis (Ph.D.) -- University of Adelaide, Dept. of Physical and Inorganic Chemistry, 1968.s. / Includes bibliography.
15

Design and synthesis of luminescent Rhenium(I) and Ruthenium(II) Diimine complexes for the recognition of ions and small molecules by host-guest interactions /

Kai, Sze-fai, Alex. January 1999 (has links)
Thesis (Ph. D.)--University of Hong Kong, 1999. / Includes bibliographical references (leaves 226-247).
16

Cationic dihydrogen complexes of rhenium with isonitrile coligands /

Voges, Mark Huggins, January 1996 (has links)
Thesis (Ph. D.)--University of Washington, 1996. / Vita. Includes bibliographical references (leaves [128]-136).
17

Syntheses, characterization, electrochemistry and photochemical properties of some high-valent Oxo and Imido complexes of osmium andrhenium

鄭郁棋, Cheng, Yuk-ki. January 1997 (has links)
published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy
18

Design and synthesis of luminescent Rhenium(I) and Ruthenium(II) Diimine complexes for the recognition of ions and small molecules byhost-guest interactions

紀思輝, Kai, Sze-fai, Alex. January 1999 (has links)
published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy
19

Synthesis and photosensitizing properties of sublimable rhenium diimine complexes

Wong, Hei-ling., 黃喜玲. January 2007 (has links)
published_or_final_version / abstract / Chemistry / Doctoral / Doctor of Philosophy
20

Synthesis and photosensitizing properties of sublimable rhenium diimine complexes

Wong, Hei-ling. January 2007 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2007. / Title proper from title frame. Also available in printed format.

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