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The impact of two constitutional isomers, 2-(4-BMes2-Ph)-pyridine (p-B-ppy) and 5-BMes2-2-ph-pyridine (p-ppy-B), as N,C-chelate ligands on the structures, stabilities, electronic and photophysical properties, and Lewis acidities of Pt(II) complexes has been investigated. Six Pt(II) complexes, Pt(p-B-ppy)Ph(DMSO), Pt(p-B-ppy)Ph(Py), [Pt(p-B-ppy)Ph]2(4,4’-bipy), Pt(p-ppy-B)Ph(DMSO), Pt(p-ppy-B)Ph(Py), and [Pt(p-ppy-B)Ph]2(4,4’-bipy), have been synthesized and fully characterized. The Lewis acidity of the complexes was examined by fluoride titration experiments using UV-Vis, phosphorescence, and NMR spectroscopic methods, establishing that the p-ppy-B complexes have stronger binding constants while the p-B-ppy complexes have a much lower affinity toward F-. A diboron compound with both 3-coordinate boron and 4-coordinate boron centers, (5-BMes2-2-ph-py)BMes2 (B2ppy) has been synthesized, which is luminescent but have a high sensitivity toward light. UV and ambient light cause this compound to isomerize via the formation of a C−C bond between a mesityl and the phenyl group, accompanied by a drastic color change from yellow to dark olive green. The structure of the dark color species was established by 2D NMR experiments and geometry optimization by DFT calculations. The dark color species can thermally reverse back to (5-BMes2-2-ph-py)BMes2 via the breaking of a C−C bond. The N, C-chelate ligand was found to play a key role in promoting this unusual and reversible photo–thermal isomerization process on a tetrahedral boron center. The impact of Pt(II) on the photoisomeration of four-coordinate boron center was also studied. The free ligand four-coordinate organoboron derivative B-ppy-ppy behaved in the same way as B2ppy. The photoisomeration process in the corresponding Pt(II) coupled complex (B-ppy-ppy)PtPh(t-Bu-py) is nearly completely deactivated, which may be attributed to either the low-lying 3MLCT excited state through which the excess energy in excited state was dissipated as phosphorescence or the greater π conjugation which can stabilize the excited state. / Thesis (Master, Chemistry) -- Queen's University, 2009-09-24 14:56:32.845

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The Cheviot Granite complex is a high-level pluton made up of six intrusive phases intruded into a pile of andesites of very similar composition to the bulk of the plutonics. The whole represents the eroded remnant of a lower Devonian volcano, erupted immediately after the continental collision that destroyed the Iapetus Ocean. The igneous history comprises two igneous cycles, both starting with basic granodiorite and including a late porphyritic ring dyke. The two cycles can be distinguished geochemically using Zr and K contents. Fractionation during each cycle involved precipitation of a biotite diorite cumulate. The second cycle ends with a highly evolved leucocratic microgranite. The geochemistry shows a rather shoshonitic - chemistry to the series, and trace elements are consistent with an immediately post-collisional origin. Hydrothermal alteration occurs in two phases, one associated in space and time with the porphyritic granodiorite of the first igneous cycle, and the other with that of the s~cond cycle. In both systems both potassic and sericitic alteration assemblages are found, and there is a wide development of propylitic alteration around these higher temperature zones. The two hydrothermal phases can be distinguished by the abundance of tourmaline in sericitic and propylitic rocks of the second cycle, and the abundance of calcium (mostly as calcite) in the sericitic rocks of the first phase. Geochemical flux calculations show that silica has been widely introduced to the granite during the alteration (in amounts up to 10\) and Ca and Sr removed. Other element fluxes are more complex, and may be coupled together. Comparison with other granites of N England and S Scotland shows that the Loch Doon complex and the Shap granite are very similar to Cheviot, that the Criffell Dalbeattie granite has a very similar early phase but diverges later, and that the Skiddaw, Weardale and Cairnsmore of Fleet granites are very different from Cheviot, being essentially granitic rather than granodioritic.

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A summary of methods from functional analysis in application to the analysis of several complex variables, based upon Hormander's estimate for ∂ operators on pseudoconvex domains.

<p>G1 and G2 dendrimeric salicylaldimine ligands containing both substituted and unsubstituted aryl rings were synthesized via a Schiff base condensation of the appropriate salicylaldehyde and the peripheral amino groups of the corresponding G1 and G2 polypropyleneimine dendrimers. The new ligands were characterized using FTIR, 1H NMR and 13C NMR spectroscopy, elemental analysis and ESI mass spectrometry. The dendrimeric ligands were converted to multinuclear nickel complexes by reaction with nickelacetate. The metal complexes were characterized by FTIR spectroscopy, elemental analysis and ESI mass spectrometry.</p> <p>Some of the dendritic complexes were evaluated as catalyst precursors in the oligomerization of &alpha / -olefins such as ethylene and 1-pentene, using aluminium alkyls such as EtAlCl2 and modified methylaluminoxane (MMAO) as activators. All the dendrimeric catalysts evaluated are active in the oligomerization reactions. From the oligomerization results it was observed that there is a clear dendritic effect, in that both catalyst activity as well as selectivity are impacted by the dendrimer generation. In most cases it was observed that the second generation complexes show higher activity than the corresponding first generation complexes.</p> <p>The dendrimeric complexes were also evaluated as catalyst precursors in the vinyl polymerization of norbornene. In this case methylaluminoxane (MAO) were employed as an activator. Once again it was noted that a dendritic effect is operative, with second generation metallodendrimers having a higher activity than the first generation complexes.</p>