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A range of fluorous monodentate triarylphosphines were synthesised using novel chemistry and modified literature methods. the corresponding complexes were shown to be more active in the Suzuki reaction, compared with the non-fluorous derivative, triphenylphosphine. However, the catalysts simply decomposed under the reaction conditions to form palladium black making it impossible for these fluorous catalysts to be recycled.;The synthesis and coordination chemistry of fluorous and non-fluorous pincer phosphines has been investigated. Both palladium pincer catalysts successfully catalyse a range of Heck and Suzuki reactions. However, recovery and reuse was only possible with the fluorous pincer catalyst, which could be successfully recovered and reused three times in the Heck reaction with no loss in activity. In the Suzuki reaction, recovery and reuse of the fluorous pincer catalyst was possible, however, decomposition of the catalyst was detected under the reaction conditions leading to an inevitable loss in activity.;A range of fluorous and non-fluorous monodentate, bidentate and pincer NHC ligands and palladium complexes were synthesised using novel chemistry and modified literature methods. The monodentate NHC complexes were evaluated in Heck reactions. The recovery and reuse of the fluorous carbene complexes were evaluated with differing success. Under homogenous reaction conditions, decomposition of the light fluorous catalyst was detected upon recovery of the catalyst. Conversely, when supporting the heavily fluorinated carbene complex on Fluorous Reverse Phase Silica Gel (FRPSG), the catalyst was successful used three times. However, due to poor recovery of the support, inevitable loss in product conversion was observed.

The investigation presents the development, analysis and iterative validation of a heterogeneous chemical kinetic model for the simulation of reactive hydrocarbon flows over noble metal catalysts. An axisymmetric, two-dimensional boundary layer system is used to model a virtual pore, physically and chemically representative of the average pore through a catalytic bed in short contact time reactors. A mechanism for the modeling of heterogeneous chemistry over palladium was developed by adopting the Unity Bond Index Quadratic Exponential Potential (UBI-QEP) for the calculation of the energetics. This was integrated, where appropriate, with results from ab initio and experimental investigations. The surface mechanism was coupled with a thoroughly validated homogeneous gas mechanism to model the oxidative dehydrogenation of ethane over an alumina supported palladium catalyst (1%Pd/Al2O3). A bimetallic palladium-platinum mechanism was constructed by coupling the palladium chemistry with a platinum mechanism previously developed with the same methodology. The refinement of the mechanism was carried out and validated with experimental measurements of ethane and ethane-acetylene co-feeds over two catalysts (0.2%Pd 3%Pt/Al2O3 and 1%Pd 3%Pt/Al2O3). Extensive investigation of the sensitivity of the model to physical and chemical parameters was undertaken and evaluated in concert with the analysis of modifications to the energetics and chemical kinetic mechanisms. Of particular significance, for the palladium mechanism, was the reduction of the atomic heat of adsorption of carbon on palladium (to 363 kJ/mol). On platinum, evidence of poisoning by acetylene confirmed the indication that an increase in the adsorption energy of acetylene (to 219 kJ/mol) would correct the balance in relative heats of adsorption of key species. The study provides a framework for the construction and development of bimetallic heterogeneous chemical kinetic mechanisms and produces a validated working model for the simulation of reacting flows over pure palladium and bimetallic palladium-platinum catalysts in a range of conditions.

The main objective of this investigation was to study palladium-catalyzed coupling of 2-aryl-4-chloro-3-iodoquinolines with phenyl boronic acid in order to assess the regioselectivity of carbon-carbon bond formation at either C3 or C4. The 2-aryl-4- chloro-3-iodoquinolines were subjected to Pd(PPh3)4-catalyzed coupling reaction with phenyl boronic acid in DMF in the presence of 2M sodium carbonate (aq) to afford 2,3-diaryl-4-chloroquinolines. Reaction of 2,3-diaryl-4-chloroquinolines with sodium methoxide in MeOH-DMF mixture under reflux afforded the corresponding 2,3-diaryl-4-methoxyquinoline. An alternative route to the latter involving palladiumcatalyzed cross-coupling reaction of 2-aryl-3-iodo-4-methoxyquinolines derived from the reaction of 2-aryl-4-chloro-3-iodoquinolines with sodium methoxide in refluxing methanol-THF mixture was also investigated. The 2,3-diaryl-4-methoxyquinolines were subjected to further studies of chemical transformation with boron tribromide to afford the corresponding 2,3-diarylquinolin-4(1H)-ones. All new compounds were characterized using a combination of NMR (1H and 13C), IR and mass spectroscopic techniques as well as elemental analysis. / Chemistry / M. Sc. (Chemistry)

The main objective of this investigation was to study palladium-catalyzed coupling of 2-aryl-4-chloro-3-iodoquinolines with phenyl boronic acid in order to assess the regioselectivity of carbon-carbon bond formation at either C3 or C4. The 2-aryl-4- chloro-3-iodoquinolines were subjected to Pd(PPh3)4-catalyzed coupling reaction with phenyl boronic acid in DMF in the presence of 2M sodium carbonate (aq) to afford 2,3-diaryl-4-chloroquinolines. Reaction of 2,3-diaryl-4-chloroquinolines with sodium methoxide in MeOH-DMF mixture under reflux afforded the corresponding 2,3-diaryl-4-methoxyquinoline. An alternative route to the latter involving palladiumcatalyzed cross-coupling reaction of 2-aryl-3-iodo-4-methoxyquinolines derived from the reaction of 2-aryl-4-chloro-3-iodoquinolines with sodium methoxide in refluxing methanol-THF mixture was also investigated. The 2,3-diaryl-4-methoxyquinolines were subjected to further studies of chemical transformation with boron tribromide to afford the corresponding 2,3-diarylquinolin-4(1H)-ones. All new compounds were characterized using a combination of NMR (1H and 13C), IR and mass spectroscopic techniques as well as elemental analysis. / Chemistry / M. Sc. (Chemistry)