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Homogeneous organometallic species serve as useful catalysts for a vast number of chemical transformations. Ancillary ligands which bind to the metal center are employed to modulate the reactivity of the metal, and have been key to the discovery and improvement of most types of transition metal-mediated reactions. This thesis describes the design and application of P,N-ligands in platinum group-catalyzed reactions, specifically the Ru- and Ir-catalyzed ketone transfer hydrogenation (TH) and the Pd-catalyzed cross-coupling of aryl (pseudo)halides and N-H containing substrates. A zwitterionic Ru-species featuring a donor substituted P,N-indenide ligand was found to be an excellent catalyst for ketone TH, providing turnover frequencies (TOFs) as high as 300 000 h-1, while related cationic Ru-complexes ligated by P,N-indene ligands were found to be rather poor catalysts. Ir-complexes supported by either indene or indenide P,N-ligands were also found to be active TH catalysts (TOFs ~30 000 h-1), however phenylene P,N ligands, specifically (o-tBu2P-C6H4)NMe2, displayed optimal catalytic performance, allowing for rapid ketone reduction (TOFs of >100 000 h-1), at low catalyst loadings (as low as 0.004 mol% Ir). Enantioselective TH was achieved by employing the suitably substituted, commercially available P,N-ligand, Cy-Mandyphos in combination with [Ir(COD)Cl]2 and NaPF6. The use of P,N-ligands in Pd-catalyzed C-N cross coupling, specifically (o-R2P-C6H4)NMe2 (R = tBu or 1-Ad), allowed for the development of a highly versatile catalyst system for this reaction. In combination with [Pd(allyl)Cl]2 or [Pd(cinnamyl)Cl]2, the above described ligands enabled the cross-coupling of aryl and heteroaryl chlorides and bromides to a diverse range of amine and related substrates such as primary alkyl- and arylamines, cyclic and acyclic secondary amines, N-H imines, hydrazones, lithium amide, and ammonia. Reactions could be performed at low catalyst loadings (0.5-0.02 mol% Pd) with excellent functional group tolerance and chemoselectivity. The ligand N-[2-di(1-adamantylphosphino)phenyl]morpholine in combination with [Pd(cinnamyl)Cl]2 was found to provide excellent reactivity for the cross-coupling of ammonia to aryl chlorides with catalyst loadings of 0.3-5 mol% Pd. Sterically unbiased substrates containing electron-donating groups were tolerated with minimal competing diarylation. Aryl tosylates could be coupled with ammonia at room temperature and chemoselective ammonia arylation in the presence of other amine functionality was well tolerated. Pd-catalyzed cross-coupling of hydrazine with aryl chlorides and tosylates was achieved employing N-[2-di(1-adamantylphosphino)phenyl]-morpholine as the ligand. Good yields of the desired, mono-functionalized aryl hydrazine product was observed for a range of substrates at 5 mol% Pd. Selective hydrazine coupling was observed in the presence of other NH-functionality and NH-indazoles could be prepared by the tandem cross-coupling/condensation of hydrazine with 2-chlorobenzaldehydes.

Herein I describe a model study to determine the feasibility of organic hydride donors as a source of hydride in the regeneration of ammonia borane. Hydride transfer was observed in the model system comprised of Hantzsch ester and several analogues, as the organic hydride donor, and tris(pentafluorophenyl)boron, as the boron-based hydride acceptor akin to BBr3. Side reactions could be minimized by varying the reaction conditions. We determined that a Lewis acid-base adduct was forming between the carbonyls of the donor and the hydride acceptor, that this adduct was dynamic in the case of Hantzsch ester and that it could be inhibited by bulkier ester groups or promoted by reducing the steric bulk at the carbonyl in the case of a methyl ketone. The thermodynamics of the hydride transfer reaction with an N-substituted analogue were probed via variable temperature NMR and compared to two differently substituted analogues. In addition, the scope of the sp2-sp3 Suzuki-Miyaura cross-coupling previously developed in our lab was extended to include 2-(1,2-diaryl)ethane pinacolborane scaffolds. In order to access this asymmetric scaffold, reaction conditions for the cross-coupling of a primary boronic ester in the presence of a secondary one were developed. Yields achieved for the linear cross-coupling were in the 70 % range and varied from 42 % to 69 % for the secondary position. These latter yields are in the same range as the hydroborated styrene scaffolds described in our first account demonstrating the broad scope of these reaction conditions. / Thesis (Master, Chemistry) -- Queen's University, 2011-09-30 14:43:02.652

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Creating new carbon-carbon bonds is one of the most important and challenging reactions in organic synthesis. Metal-catalyzed cross-coupling reactions have emerged as one of the preferred methods of producing new carbon-carbon bonds, and this work led to the 2010 Nobel Prize in Chemistry. This thesis was aimed at expanding the current research in the area of metal-catalyzed cross-coupling reactions to include new applications with dithiolane and dithiane protecting groups. 1,3-Dithiolane and 1,3-dithiane derivatives are particularly interesting molecules in that they can be deprotonated by a strong base to form anions, which can then be used for carbon-carbon bond synthesis. This thesis describes the investigation into the use of dithiolanes and dithianes in metal-catalyzed cross-coupling reactions, as well as some of the challenges faced in performing this sulfur-based chemistry.

This thesis examines the connections between Japanese gardens, Modernism and Japanese-inspired gardens in New Zealand. The link between traditional Japanese gardens and Modernism is a familiar theme for scholars of architecture, design and landscape architecture. A less considered route of scholarship is the relationship between historical Japanese garden designs, Modernist-inspired gardens in Japan, and New Zealand garden design. A historical foundation provides a base on which to analyse any later changes or transmissions. By analysing the history of Japanese gardens and Modernism, through select key figures, one can also grasp their complexities and outline wider trends. Connecting these somewhat divergent entities is important due to the fact that these gardens represent a myriad of global translations. They represent the modernisation and globalisation of Japan and New Zealand as well as trends in New Zealand‟s artistic and cultural community. The success of the translation of Japanese traditions into New Zealand was due to, in part, the production of a regional idiom. New Zealand‟s Japanese-inspired gardens represent the integration of Japanese and New Zealand traditions, materials and ideas. The result is a hybrid garden, a garden which forms its own specific regional peculiarities which symbolises the many connections between Japan and New Zealand.

This thesis examines the conditions under which ethno-territorial cross-border conflicts can be resolved successfully. Ethno-territorial cross-border conflict is a type of ethnic conflict in which competing territorial and ethnic claims of distinct state and group actors occur; and this manifests itself primarily on three interrelated levels - inter-group conflict, conflict between the external minority and the institutions of its host-state, and the (territorial) conflict between host- and kin-state. An initial theoretical exploration of the subject establishes the framework of the subsequent study of individual cases, examining why the similar conflicts in Alsace, the Saarland, South Tyrol, and Northern Ireland required fundamentally different solutions. In addition to this, the condominia of Andorra and the New Hebrides are analysed, providing the basis upon which the concept of a condominium-style settlement for ethno-territorial cross- border conflicts is explored. By looking at the workings of integration, traditional consociation and consociation with permanent institutionalised kin-state involvement, secession, and condominium, the complexity of factors is studied that influence the development of ethno- territorial cross-border conflict, including inter-ethnic and intra-ethnic dimensions and the policies of the host and kin-state in relation to the conflict and each other. Thus refined, the analytical framework allows determining the conditions that must be fulfilled to provide lasting stability to a negotiated settlement. This set of stability criteria creates a paradigm that has relevance as an analytical tool beyond the case studies conducted in this thesis. It can be used to design case-specific solutions to actual ethnic conflicts and it can serve as an instrument to recognise instabilities in, and potential breakdowns of, existing settlements sufficiently early to respond to them constructively and to avoid a re-escalation of an already settled conflict.

This thesis examines the international growth and diversification of real estate advisory services in the United States, the United Kingdom, Germany, and Japan from over a 30-year period, 1960-1990. These four countries were selected because they were the most active in cross-border direct investment during this period, and intricate economic interdependencies among them prompted the greatest advancements in innovative real estate advisory services. Economic and cultural differences and similarities among the four focal countries and their respective service professions provide the bases for evaluating the primary hypothesis: the internationalization of real estate advisory services were most efficiently and effectively achieved by firms that first built solid reputations in their home nations, and subsequently expanded into multiregional organizations by responding to the cross-border investment activities of existing and prospective multinational clients. If leading firms in the focal countries expanded in domestic markets to capitalize on the national economy's maturing real estate markets, then moved into foreign markets to capitalize on rising cross-border investment flows over the 1960-1990 period, the primary thesis raises a question about the relative significance of cross-border real estate investment to national economic conditions, generally, and to the growth of commercial real estate markets and sectoral employment in the focal countries, specifically. A secondary hypothesis, therefore, is tested to identify the relative impact of total cross-border real estate investment flows on employment levels in the commercial real estate sector in the U.S., U.K., Germany, and Japan. This thesis also examines the several dimensions of the economy and financial system affected by domestic and foreign investment in commercial real estate assets after 1960. For example, rising worldwide commercial property investment appeared to be an important factor in the escalation of corporate real estate values, in the growth of construction industries and related services sectors, in the changes in the net worth of major financial institutions, and in the asset diversification of insurance and pension fund portfolios. As part of this trend, the growth of international business and the rise in mergers and acquisitions also elevated cross-border direct investment activity in real estate as companies expanded into foreign markets. This thesis explores the process by which property advisory services internationalized and gained an important role in the global service economy by counseling investors on the location and volume of investment activities, and thereby influencing the international flow of real estate investment funds. It also examines whether real estate advisory firms in the focal countries gained competitive advantage over the 30-year period due to the presence of two basic conditions: an international network of property professionals; and a diversified services practice--brokerage, property management, finance, facilities planning and development, and real estate sales and purchases. By reviewing national fluctuations in cross-border direct investment in real estate, and periodic changes and major episodes in the foreign expansion of real estate advisory services in the focal countries, this thesis seeks to examine specific national factors that influenced effective internationalization in domestic property services. Basic principles in economic history provide the theoretical framework concerning competitive and comparative advantages among nations and particular organizations.