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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.
71

The activity of silica immobilized palladium N-heterocyclic carbene complexes toward Mizoro-Heck reaction and their characterization/Özge Aksın;thesis advisor Levent Artok.

Aksın, Özge. Artok, Levent January 2005 (has links) (PDF)
Thesis (Master)--İzmir Institute of Technology, İzmir, 2005. / Keywords: Palladium, Immobilization, Heck Reaction, Palladium-N-Heterocyclic Carbene, Carbon-Carbon Coupling. Includes bibliographical references (leaves. 89-104).
72

Investigation of the chemoselectivity and efficiency of the benzannulation reaction of electron poor aryl Fischer carbene complexes : synthetic studies toward (+)-olivn /

Liptak, Vincent Paul. January 2000 (has links)
Thesis (Ph. D.)--University of Chicago, Dept. of Chemistry, August 2000. / Includes bibliographical references. Also available on the Internet.
73

Synthesis of metal complexes with thiophene ligands /

Landman, Marile. January 2000 (has links)
Thesis (Ph.D.(Chemistry))--University of Pretoria, 2000. / Includes abstract in English and Afrikaans. Includes bibliographical references. Also available online.
74

N-heterocyclic carbenes from heterocyclynes to potential radiopharmaceuticals /

Quezada, Carol A. January 2005 (has links)
Thesis (Ph. D.)--University of Akron, Dept. of Chemistry, 2005. / "May, 2005." Title from electronic dissertation title page (viewed 09/24/2005). Includes bibliographical references.
75

Novel carbene complexes with pyrrole ligands

Olivier, Andrew John. January 2001 (has links)
Thesis (M.Sc.(Chemistry))--University of Pretoria, 2001. / Summaries in Afrikaans and English.
76

Carbenes and carbenoids as powerful tools in organic synthesis

Frankowski, Kevin J. January 2006 (has links)
Thesis (Ph.D.)--University of Delaware, 2006. / Principal faculty advisor: Douglass F. Taber, Dept. of Chemistry and Biochemistry. Includes bibliographical references.
77

Synthetic studies towards fostriecin (Cl-920) /

Parisi, Mark P. January 1999 (has links)
Thesis (Ph. D.)--University of Chicago, Dept. of Chemistry, August 1999. / Includes bibliographical references. Also available on the Internet.
78

New transition metal carbene complexes for application in homogeneous catalysis /

Julius, Gerrit Richard. January 2005 (has links)
Thesis (PhD)--University of Stellenbosch, 2005. / Bibliography. Also available via the Internet.
79

Nuwe reaksies van gedeprotoneerde Fischer-tipe karbeenkomplekse /

Stander, Elzet. January 2005 (has links)
Thesis (MSc)--University of Stellenbosch, 2005. / Bibliography. Also available via the Internet.
80

Tiasole en tiofene as uitgangstowwe vir die bereiding van karbeen- en ander koördinasiekomplekse

Greyling, Denise Karola 12 September 2012 (has links)
M.Sc. / This study focussed on two areas of research in the field of organometallic chemistry. The first entails the preparation and characterisation of a number of Fischer-type carbene complexes of the general formula (C0) 5M(OR)(RI) (1 - 4). For the first group M = Cr, Mo or W, R = Et or Me and re = Ph or BiPh. A second, somewhat different group was prepared by deprotonating 4- methylthiazol-2-methyltlfioether, reacting it with M(CO) 6, where M = Cr or W, and neutralising the resulting anion with methyltriflate. Both metals afforded only one product which could be successfully purified and characterised as M(C0),{C(OCH3)(C=C(CH3)N=C(SCH3)S) (6,7). The crystal structure of the tungsten complex was solved by single crystal X-ray techniques. A similar carbene complex preparation was carried out with 5-methylthiophenilyl-2-thiomethylether and M(C0)6, M = Cr or W, as starting reagents. In addition to the expected carbene complexes M(CO)5 (C(OCH3)(CH2SHCH=C(CH3)S)), M = Cr and W (9a, 10a), deprotonation of a ring carbon yielded M(C0) 5{C(OCH3)(6=C(SCH3)SC(CH3)=CH)) M = Cr and W (9b, 10b), whereas unreacted starting material afforded the sulfide W(C0) 54-SC(SCH3)=CHCH=C(CH3) (11). The second part of the thesis describes the preparation of pentacarbonyl thione and iminocomplexes, as well as tricarbonyl imino-, sulphide and dinuclear re-sulphide complexes. 4- Methylthiazoly1-2-thiolate were used for nucleophilic attack on (C0) 5Cr--C(OR)(12. 1) (1 and 4) to yield the thione complex Cr(C0) 54-S=CN(CH3)C(CH3)=CHS (13) upon methylation. Two other products were also obtained from these reactions : Cr(C0) 54-NC=CHSCH=C(CH3) (12) and Cr(CO) 54-N=C(CH3)SCH=C(CH3) (14), which indicates incomplete reaction with sulfur during the formation of the mentioned thiolate. Three beautiful electron ligand systems were produced by reacting 4-methylthiazol-2-disulphide with (CO),W(THF) or Fe2(C0)) . A new "butterfly" bidentately coordinated tricarbonyl tungsten complex, [(C0)3 1/{N(S)SCH(CH3)) 2] (16) was obtained. The crystal structure of this complex shows many similarities to a known complex, (C0)3W(n2-PyS)2 that was prepared from ionic metalcarbonyl precursors. In addition to 16, a thione complex W(C0) 54-SHC(CIi )=CHS (17) also formed from the reaction with (CO) 5M(THF). The reaction between (CO),M(THF) and 4-methylthiazolyi-2-disulphide thus probably involves heterolytic bond cleavage and protonation on the silica gel. The reaction of Fe 2(CO)9 with the same disulphide resulted in the formation of the dinuclear compound Fe2(C0)6(SC=NC(CH3)=CHS)2 (18), possibly via the homolytic splitting of the disulphide bond. The crystal structure of this compound revealed the Fe-Fe-bond and eclipsed configuration, typical of this type of Fe-cluster complex. Finally, two thione complexesM(C0)54—S(SMe)(eHCH(Me)S), (M= Cr and W; 20,21) were found to isomerise in solution to their sulphide analogues of which only the chromium complex Cr(C0)54— SC(Me)=CHCH=C(C(=S)(SMe)) (22) could be characterised.

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