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Document incorrectly classified as a dissertation on title page (decision to classify as a thesis from NDSU Graduate School) / Organocatalysis is a field that has bloomed over the last decades. With the field’s promise of being able to mimic nature and afford products in a synergistic manner to traditional Lewis acid catalysis, several interesting discoveries have been made. Owing to the vastness of the field as it exists today, this document will focus on two main aspects; cinchona alkaloid (and derivatives) as used in common carbon-carbon bond forming reactions and kinetic resolution via 4-dimethyl aminopyridine-N-oxide derivative driven acylation. Kinetic resolution via organocatalysis has the potential to react one enantiomer of a racemic mixture without affecting the other. The highlight of this screening was an s factor of 9 which was produced using optimized conditions using a catalyst designated DMAPO-IV. There remains much to do in improving the system and elucidating the scope of this catalytic system this report details the efforts made thus far.

<p> This thesis is primarily concerned with an investigation of the reaction of tetrakis(tri-p-tolyl phosphite)nickel(0) with strong acids, using 1H, 31P and 2H NMR. The results differ from those previously obtained for similar reactions with other Ni(0) phosphites, in that both five and four-coordinate nickel hydrides are formed in concentrations sufficient for spectroscopic studies. The four-coordinated hydride is believed to be the catalytically active species in a number of reactions catalyzed by Ni(0) phosphites. Variable-temperature studies show that the four-coordinate hydride complex is a fluxional molecule. The exchange process is exclusively intramolecular in nature.</p> <p> A very simple method was used to analyze the NMR data and obtain activation parameters for the exchange process. These parameters were compared with those reported in the literature for related intramolecular and intermolecular reactions. The large negative entropy of activation is interpreted in terms of ion pairing in the transition state. NMR evidence for the structure of the products resulting from the reactions of acids with both the metal complexes and the free phosphite ligands is presented. The conditions necessary for the observation of four-coordinated nickel hydrides are also discussed.</p> / Thesis / Master of Science (MSc)

The phosphazene ligands spiro(biph)tetrakis(2-oxypyridine)cyclotriphosphazene (L1), spiro(biph)tetrakis(4-methyl-2-oxypyridine)cyclotriphosphazene (L2), and spiro(biph)tetrakis(6-methyl-2-oxypyridine)cyclotriphosphazene (L3 In solution, [CuL) have been synthesised and characterised as small molecule templates for the polymeric analogues. Complexes of each ligand with selected transition metals have been synthesised and characterised. Where X-ray crystal structures have been obtained, the predominant geometry is a five-coordinate trigonal bipyramidal (TBP) form, though variations exist. 2Cl2] retains the TBP form whereas [CoL2Cl2 ] rearranges to a tetrahedral geometry. In order to elucidate this behaviour, diamagnetic complexes were synthesised and variable temperature NMR (VTNMR) studies conducted. The complexes [ZnL2Cl2], [CdL2Cl2] and [HgL2Cl2] exhibit fluxional behaviour as monitored by VTNMR studies. The X-ray structure of [CdL2Cl2] contains three molecules in the unit cell that demonstrate what is thought to be the first evidence for a fluxional mechanism in phosphazene compounds. The complex [ZnL2Cl2 ] exists at low temperature as discernable major and minor species. Polyphosphazene analogues have been synthesised and complexed with selected transition metals. The polymer complexes display variations in solubility and stability which is postulated to be due to the ratio of side group substitution, position of the pyridyl methyl group and the nature of the complexing metal. A number of the polymers degrade prior to workup, possibly as a result of base-promoted attack on the backbone by the pyridyl nitrogen atoms. Electronic spectra reveal that where soluble, the Co(II) polymer complexes have a tetrahedral geometry, whereas the Cu(II) polymer complexes distort between TBP and square-based pyramidal dependent on the ratio of metal used. Polymer complexes with Zn(II) demonstrate fluxional behaviour.