Asymmetric catalysis is one of the most effective ways to control a target molecule’s stereochemistry. Through the development of a wide variety of chiral transition metal complexes, synthetic chemists are given the tools they need to synthesize the desired enantiomer of numerous compounds. This work focuses on exploiting the non-innocent ligand reactivity of metal bis-dithiolenes with multiple conjugated π systems in order to synthesize chiral ligands. Recent work has shown that platinum bis-dithiolene reacts with dienes stereoselectively to form a racemic mix of C2 -chiral thioether ligands. The present contribution will show approaches to synthesizing chiral dienes and organometallic complexes with potential applications for asymmetric allylic substitution reactions. Dienes with various chiral auxiliaries were reacted with platinum dithiolene and monitored through NMR spectroscopy. Attempts to synthesis palladium bis-dithiolene complexes, not previously seen in the literature were made, and the reaction of α-β unsaturated ketones with metal bis-dithiolenes was explored.

Asymmetric catalysis is one of the most effective ways to control a target molecule’s stereochemistry. Through the development of a wide variety of chiral transition metal complexes, synthetic chemists are given the tools they need to synthesize the desired enantiomer of numerous compounds. This work focuses on exploiting the non-innocent ligand reactivity of metal bis-dithiolenes with multiple conjugated π systems in order to synthesize chiral ligands. Recent work has shown that platinum bis-dithiolene reacts with dienes stereoselectively to form a racemic mix of C2 -chiral thioether ligands. The present contribution will show approaches to synthesizing chiral dienes and organometallic complexes with potential applications for asymmetric allylic substitution reactions. Dienes with various chiral auxiliaries were reacted with platinum dithiolene and monitored through NMR spectroscopy. Attempts to synthesis palladium bis-dithiolene complexes, not previously seen in the literature were made, and the reaction of α-β unsaturated ketones with metal bis-dithiolenes was explored.

The novel chelating ligand, Me[NOON]H2 (N,N'-((ethane-1,2-diylbis(oxy))-bis(ethane-2,1-diyl))- bis(2,6-dimethylaniline)), have been synthesized successfully and characterized by NMR. The lithium complexes of the aryl diamide ligand have also been synthesized by n-BuLi react with neutral ligand, Me[NOON]H2. And the lithium complexes is a ether adduct according to the 1H NMR. The lithium complex, Me[NOON]Li2(OEt2) react with Ti(OiPr)4 and TiCl4(THF)2 to form the NOON titanium alkoxide and dichloride complexes respectively, and they have been characterized by 1H NMR and X-ray diffraction. These NOON titanium complexes are expected to be a catalyst for the ring opening polymerization of lactide or caprolactone in the future. The tantalum complexes of diphenolate phosphine ligands have been synthesized and characterized successfully by NMR, X-ray diffraction, and elemental analysis. The tantalum complexes, [tBuOPO]2TaX (X=Me, Et, H) is produced by the reaction of [tBuOPO]2TaCl with Grignard reagent (MeMgBr and EtMgCl) and superhydride(LiHBEt3). These tantalum complexes will be applied in dinitrogen activation in the future work.

The late transition metal complexes containing sulfide ligands have trem- endous applications not only in biochemistry but also in industrial catalysis. We have successfully synthesized four different bidentate ligands, 2- (Benzylidene)benzenethiol(NS-1), 2-[2,6-(Dimethylbenzylidene)]benzenethi- ol(NS-2), 2-(2-Chloro-1-methylethylidene)benzenethiol(NS-3) and 2-(Diphe- nylphosphanyl)benzenethiol(PS), and five tridentate ligands, N-{N-[2-(Diph- enylphosphino)benzylidene]-2-sec-butylethylsulfide}(PNS-1), N-{N-[2-(Di- phenylphosphino)benzylamino]-2-sec-butylethylsulfide}(PNS-2), 2-[2-(Diph- enylphosphino)phenylsulfanylmethyl]pyridine(PSN-1), 2-[2-(Diphenylphos- phino)phenylsulfanyl]ethylamine(PSN-2) and 2-(Diphenylphosphino)phenyl- sulfanylacetonitrile(PSN-3). These ligands reacted with the late transition metal (Zn, Ag, Pd, and Ni) salts, and produced complexes 1-12. Besides their spectra, we also obtained crystal structures of complexes 3, 4, 5, 6, 7, 8, 9, 10, 11, and 12. We found that the PNS tridentate ligands had different bonding modes in zinc, silver, palladium, and nickel complexes. For examples, in zinc complexes 1 and 2 only P and S atoms were coordinated to the metal while all P, N, and S atoms were coordinated to the Pd metal in Pd complexes. It indicated that thiolether prefers to coordinate to palladium but not to zinc in our cases. When PNS-2 went through different reaction routes, two silver complexes 4 and 5 with different coordination modes a M2L2 type dinuclear complex and a ML2 type mononuclear complex were obtained.. When reacting PNS-2 with nickel, we obtained an unique tetranuclear nickel complex 6. PSN-1 showed two different coordinate modes in complexes 8-10 while PSN-2 and silver produced a dinuclear silver complex 11 that resembled complex 4. PSN-3 coordinated to Pd ion by phosphorus and sulfide atoms. As such, we demonstrated the various coordinated modes in PNS and PSN ligands. Finally PS bidentate ligand reacted with zinc salt produced complex 7 with one oxidized ligand. The variable temperature NMR experiment was also used to probe the structural change that occurred in solution state for 3.

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Thesis (M. S.)--Biomedical Engineering, Georgia Institute of Technology, 2006. / Committee Chair: Zhu, Cheng; Committee Member: Babensee, Julia; Committee Member: Dustin, Michael; Committee Member: Garcia, Andres; Committee Member: Jo, Hanjoong; Committee Member: van der Merwe, Anton. Part of the SMARTech Electronic Thesis and Dissertation Collection. Non-Latin script record

Thesis (M. Sc.)--York University, 2001. Graduate Programme in Biology. / Typescript. Includes bibliographical references (leaves 106-118). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://wwwlib.umi.com/cr/yorku/fullcit?pMQ66399.

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Thesis (Ph. D.)--Northeastern University, 2008. / Title from title page (viewed Aug. 5, 2009). Graduate School of Arts and Sciences, Dept. of Chemistry and Chemical Biology. Includes bibliographical references.

According to the famous axiom known as Moore’s Law the number of transistors that can be etched on a given piece of silicon, and therefore the computing power, will double every 18 to 24 months. For the last 40 years Moore’s prediction has held true as computers have grown more and more powerful. However, around 2020 hardware manufac-turers will have reached the physical limits of silicon. A proposed solution to this dilemma is molecular electronics. Within this field researchers are attempting to develop individual organic molecules and metal complexes that can act as molecular equivalents of electronic components such as diodes, transistors and capacitors. By utilizing molecular electronics to construct the next generation of computers processors with 100,000 times as many components on the same surface area could potentially be created. We have synthesized a range of new pyridyl thienopyridine ligands and compared the electrochemical and photophysical properties of their corresponding Ru(II) complexes with that with the Ru(II) complexes of a variety of ligands based on 6-thiophen-2-yl-2,2´-bipyridine and 4-thiophen-2-yl-2,2´-bipyridine. While the electrochemistry of the Ru(II) complexes were similar to that of unsubstituted [Ru(bpy)3]2+, substantial differences in luminescence lifetimes were found. Our findings show that, due to steric interactions with the auxiliary bipy-ridyl ligands, luminescence is quenched in Ru(II) complexes that in-corporate the 6-thiophen-2-yl-2,2´-bipyridine motif, while it is on par with the luminescence of [Ru(bpy)3]2+ in the Ru(II) complexes of the pyridyl thienopyridine ligands. The luminescence of the Ru(II) com-plexes based on the 4-thiophen-2-yl-2,2´-bipyridine motif was en-hanced compared to [Ru(bpy)3]2+ which indicates that complexes of this category are the most favourable for energy/electron-transfer sys-tems. At the core of molecular electronics are the search for molecular ON/OFF switches. We have synthesized a reversible double cyclome-tallated switch based on the Ru(tpy) complex of 3,8-bis-(6-thiophen-2-yl-pyridin-2-yl)-[4,7]phenanthroline. Upon treatment with acid/base the complex can be switched between the cyclometallated and the S-bonded form. This prototype has potentially three different states which opens the path to systems based on ternary computer logic.