Thesis (Ph. D.)--University of Adelaide, Dept. of Physics, 1984. / Includes bibliographical references (leaves 117-124).

Thesis (Ph. D.)--Dept. of physics, University of Adelaide, 1983. / Includes bibliographical references.

Thesis (M.S.)--Baylor University, 2007. / Includes bibliographical references (p. 95-98).

No description available.

An array of different cyclopropanes have been synthesised, including the structurally simple 1-phenylcyclopropanol. These were synthesised in yields upwards of 60%, using the well published Kulinkovich reaction. From 1-phenylcyclopropanol, variations of the cyclopropane core structure were synthesised, creating species ideal for palladium cross coupling reactions, such as 1-phenylcyclopropyl methanesulfonate and 1-phenylcyclopropyl 4-methylbenzenesulfonate. These were formed in 50 and 60% yield respectively. Once obtained these cyclopropanes were used to perform Suzuki cross coupling reactions towards the formation of 1,1- diphenyl cyclopropane. Unfortunately, despite various attempts, the palladium cross coupling reactions were unsuccessful. The work did facilitate the discovery of a novel methodology for the synthesis of tetra substituted alkenes. Using similar methodology as that developed for the formation of 1- phenylcyclopropanol, a McMurry reaction was able to be performed on a number of different ketones. This reaction formed a wide array of different tetra-substituted alkenes with yields ranging from 20-99%, depending on the nature of the starting material. The method, involving the use of 9 equivalents of Grignard reagent and stoichiometric amounts of titanium isopropoxide, is a unique way of making low valent titanium in situ, as well as being homogeneous. Methodology for the formation of vinyl cyclopropanes containing an amide moiety has been developed, allowing a variety of different amines to be coupled to two different cyclopropanes. Once these species were synthesised, a palladium catalysed cyclisation, Heck reaction, carbonylation cascade was developed. This allowed the core cyclic structure of the stemona alkaloids to be obtained in a single reaction vessel with good yields of up to 52% depending on the amine used. The cascade was then applied to a fully substituted cyclic natural product core. However, the cascade reaction was unsuccessful. Efforts to alter the structure of the starting material, to remove the potentially hindering bromine, provided no improvement. It was established that the tetrakis(triphenylphosphine) palladium (0) catalyst used was too encumbered for insertion in to the sterically hindered starting material, which is likely to be causing the failure of the reaction.

Au(I) catalysis has recently emerged as a powerful tool for the realization of a broad range of organic transformations. Despite this rapid development, attaining selectivity and maintaining catalyst stability remain significant challenges. Rational ligand design, such as the employment of NHC or TA ligands, has been used to confront these issues. This thesis focuses on the use of Au(I) catalysts bearing these ligands for the selective hydroalkynylation of enol ethers. By employing a TA-Au stabilized catalyst, [(OAr)3PAu(TA-H)]OTf, the intermolecular hydroalkynylation of enol ethers, a substrate that is well-known to promote decomposition of the gold cation, was efficiently achieved. As an expansion of this reaction, the NHC-Au catalyst, IPrAuNTf2, was utilized in a multicomponent system to promote the tandem hydroalkynylation of enol ethers formed in-situ via the cycloisomerization of alkynols. Further exploration of this tandem reaction revealed that IPrAuNTf2 catalyzes a cascade ring-expansion of the alkynylated heterocycles to form oxepines. The mechanistic and synthetic insight obtained from these developed reactions has the potential to be applied towards future studies in gold catalysis.

The temporal and spatial patterning that underlies morphogenetic events is controlled by gene regulatory networks (GRNs). These operate through a combinatorial code of DNA – binding transcription factor proteins, and non – coding DNA sequences (cis-regulatory elements, or CREs), that specifically bind transcription factors and regulate nearby genes. By comparatively studying the development of different species, we can illuminate lineage – specific changes in gene regulation that account for morphological evolution. The central nervous system of vertebrates is composed of diverse neural cells that undergo highly coordinated programs of specialization, migration and differentiation during development. Approximately 20% of neurons in the cerebral cortex are GABAergic inhibitory interneurons, which release the neurotransmitter gamma-aminobutyric acid (GABA). Diseases such as autism, schizophrenia and epilepsy are associated with defects in GABAergic interneuron function. Several members of the distal-less homeobox (Dlx) transcription factor family are implicated in a GRN underlying early GABAergic interneuron development in the forebrain. I examined the role played by orthologous dlx genes in the development of GABAergic interneurons in the zebrafish forebrain. I found that when ascl1a transcription factor is down-regulated through the micro-injection of translation – blocking morpholino oligonucleotides, Dlx gene transcription is decreased in the diencephalon, but not the telencephalon. Similarly, gad1a transcription is also decreased in this region for these morphants. As gad1a encodes an enzyme necessary for the production of GABA, these genes are implicated in a cascade underlying GABAergic interneuron development in the diencephalon.

The use of H2O as an additive in SmI2-mediated reductive processes provides access to new transformations and previously inaccessible chemical space. The cyclisation of radicals derived from the selective mono-reduction of Meldrum’s acid derivatives was further investigated and the scope of the methodology expanded to cyclisation cascades. The first general methodology for the reduction of amide-type carbonyls under single electron transfer conditions was developed and applied to the mono-reduction of barbituric acid derivatives, providing an unprecedented direct access to the corresponding hemiaminals with a good degree of stereocontrol. The intermediate acyl-type radicals were in addition successfully exploited in stereoselective radical cyclisations. The hemiaminals derived from mono-reduction and cyclisation of barbituric acid derivatives have been exploited as N-acyliminium equivalents, affording hydrouracils with an excellent degree of regio- and stereoselectivity. Efforts towards the synthesis of the azulene framework of pseudolaric acid B using a model substrate are also described.

The U.S. Forest service, recognizing the scenic, scientific, and educational value of the Cascade Springs area near Mount Timpanogos, has set aside and begun development of this spot for the use of the general public. As part of their preparatory work they have asked that examination be made of the flora, fauna 9 and physical features which may in part be incorporated into public informational facilities being constructed at the springs.

The Willamette Pass area is situated at the intersection of two hypothesized structural features, the Western Cascade-High Cascade boundary and the Eugene-Denio lineament. It is of interest due to its designation by the U.S. Department of the Interior as a Known Geothermal Resource Area.