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Luminescent cyclometalated gold (III) complexes with ancillary N-heterocyclic carbene and alkynyl ligands : from design, synthesis, photophysics to supramolecular assembly and functionsAu, Ka-man, 區嘉雯 January 2012 (has links)
A library of luminescent cyclometalated gold(III) complexes containing
various bis-cyclometalating R-C^N^C ligands derived from 2,6-diphenylpyridine
and ancillary alkynyl ligands, [Au(R-C^N^C)(C≡CR’)], has been synthesized.
Some of the complexes have been structurally determined by X-ray
crystallography. These complexes were found to exhibit intense emission in
dichloromethane solution at 298 K, originating from metal-perturbed triplet
intraligand (IL) excited states of the R-C^N^C ligand, with substantial charge
transfer character from the aryl moiety to the pyridyl ring. In the presence of
electron-rich alkynyl ligands, the emission origin could be switched to an
alkynyl-to-cyclometalating ligand ligand-to-ligand charge transfer (LLCT) excited
state. This class of complexes was also demonstrated to show rich
electroluminescence properties as emitters in organic light-emitting devices. In
addition, the supramolecular assembly of this class of complexes has also been
revealed in gelation studies.
N-Heterocyclic carbenes have been incorporated into the gold(III) metal
center to prepare a series of luminescent mononuclear and dinuclear gold(III)
complexes, [{Au(C^N^C)}n(NHC)](PF6)n and [{Au(tBuC^N^CtBu)}n(NHC)]-
(PF6)n
(n = 1, 2). The X-ray crystal structures of most of the complexes have been
determined. The emissions of these complexes were assigned to originate from the
metal-perturbed intraligand excited state of the bis-cyclometalating ligand. One of
the C2-bridged dinuclear complexes was found to exhibit two distinct reduction
couples, tentatively correlated to the presence of significant intramolecular π-π
interaction in the complex.
Two novel series of luminescent mononuclear alkynylgold(III) complexes,
[Au(C^N)(C≡CR)2] (HC^N = 2-phenylpyridine (Hppy) and derivatives) and
[Au(C^N^N)(C≡CR)]PF6 (HC^N^N = 6-phenyl-2,2’-bipyridine and derivatives),
have been synthesized. Some of the X-ray crystal structures have been determined.
The former class of complexes with bidentate C^N ligands has been observed to
show tunable emission spanning across the visible spectrum from 462 to 697 nm.
With the exception of [Au(ppy)(C≡C-C6H4-NH2-p)2] which showed a low-energy
band originated from a 3LLCT [π(C≡C-C6H4-NH2)→π*(C^N)] excited state, all
complexes exhibited vibronic-structured emission bands originated from the
intraligand transition of the cyclometalating C^N ligand in dichloromethane
solution at 298 K. On the other hand, most of the complexes with the tridentate
C^N^N-type ligand have been observed to exhibit vibronic-structured emission
bands attributed to the intraligand transition of the C^N^N ligand in
low-temperature butyronitrile glass. / published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy
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82 |
Addition reactions of some substituted indoles with dimethyl acetylenedicarboxylate and methyl propiolate蔡志強, Choi, Chi-keung, Michael. January 1983 (has links)
published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy
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83 |
Disposition and hepatotoxicity of 1,2-dibromoethanePlescia, Frank Harry January 1981 (has links)
No description available.
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84 |
Mass spectrometric studies and cryogenic reactivity of CF[subscript]2 and CI[subscript]2Martin, William Joseph 05 1900 (has links)
No description available.
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85 |
Heats of mixing for liquid systems containing chloride, hydroxyl and methylene groups : measurement and prediction by an analytical group solution modelKalu, Egwuonwu Ukoha. January 1975 (has links)
No description available.
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86 |
Metabolic impairment of the posterior cingulate cortex and reversal by methylene blue a novel model and treatment of early stage Alzheimer's disease /Riha, Penny Denise, January 1900 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2007. / Vita. Includes bibliographical references.
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87 |
Rate constants and mechanisms for reactions of carbenes and cations from oxadiazolines and other precursors /Pezacki, John Paul. January 1998 (has links)
Thesis (Ph.D.) -- McMaster University, 1999. / Includes bibliographical references (leaves 260-271). Also available via World Wide Web.
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88 |
N-heterocyclic carbenes with pendant arylamine donor substituents as supports for metal-metal interactions of closed shell metal ionsMoore, Adam L. January 2008 (has links)
Thesis (Ph. D.)--University of Nevada, Reno, 2008. / "December, 2008." Includes bibliographical references. Online version available on the World Wide Web.
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89 |
Rhodium-mediated carbene insertion synthesis of (-)-hamigeran B and the (-)-sordaricin core /Tian, Weiwei. January 2008 (has links)
Thesis (Ph.D.)--University of Delaware, 2008. / Principal faculty advisor: Douglass F. Taber, Dept. of Chemistry & Biochemistry. Includes bibliographical references.
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90 |
Reactivity of bis(amino)cyclopropenylidenes (BACs) and cyclic (alkyl)(amino)carbenes (CAACs) coordination chemistry, catalysis, and small molecule activation /Kuchenbeiser, Glenn Richard. January 2009 (has links)
Thesis (Ph. D.)--University of California, Riverside, 2009. / Includes abstract. Available via ProQuest Digital Dissertations. Title from first page of PDF file (viewed March 10, 2010). Includes bibliographical references. Also issued in print.
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