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Research has been conducted on bis(o-azaheteroaryl)methanes. The synthesis of these compounds and their coordinated properties toward divalent transition metals have been investigated and the results are reported.

Research has been conducted on the pyridoneimines and pyridonemethides. The preparation and characterization of these compounds have been carried out in in investigating the possibility to finely tune pi-electron structure properties via examining the substituent and solvent effects, and the use of the multinuclear NMR and UV-vis spectroscopy is described.

Research has been conducted on the trisubstituted oxiranes. The synthesis of these oxiranes based on the deprotonation-alkylation of the stereodefined simpler oxazolinyloxiranes has been carried out and the results are discussed.

Research has been conducted on the synthesis of triazolyl derivatives. The use of multinuclear NMR spectroscopy in investigating carbanions is discussed.

The lithium enolate of p-phenylisobutyrophenone in tetrahydrofuran (THF) exists as tetramer contact ion pairs at higher concentrations although there is still a significant level of the monomeric form. Alkylation reaction studies using a variety of alkylating agents reveal that this reaction is first order based on the concentration of the monomer in THF. This suggests that the monomer is the reactive species in alkylation reactions.

Ultraviolet spectral analysis of the cesium enolate of p-phenylisobutyrophenone in tetrahydrofuran (THF) reveals that the spectrum varies with the concentration of the solution. Singular value determinations over a wide range of concentration show that more dilute solutions have longer wavelength maxima. Further investigations also reveal that ion pair monomers are the dominant species in alkylation reactions of cesium enolates in THF.

It has been shown that the cesium salt of dephenylamine will aggregate more readily than the lithium salt, and that the absorption spectra for the monomer and dimer of the cesium salt are measurably different. These properties for carbazole, a related acidic amine, are compared, and the corresponding ion pair acidities of carbazole is reported.

The characterization of two new purinyl derivatives, 8-benzyl-7methylpurine and bis(7-methylpurin-8-y)methane, was performed and their corresponding carbanions examined in DMSO. The C NMR spectrum reveals the presence of the carbanions of both purinyl derivatives as a mixture of geometric isomers, a conseqence of the high double-bond character along the bond linking the carbanionic carbon to C(8) of the purinyl ring. Results indicate that bis(7-methylpurin-8-yl)methane reacts with metal acetates to produce neutral methanates.

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A detailed NMR investigation of alpha-heterosubstituted chloroethyllithiums in tetrahydrocortisol was conducted. The generation and NMR study results of (2-(alpha-chloroethyl)benzothiazolyl)lithium and (4,4-dimethyl-2-(alpha-chloroethyl)oxazolinyl)lithium are described. Semiempirical calculations were also included to complement and support the NMR results.

The B3LYP/PM3 approach gives seemingly reliable aggregation and coordination energies for the lithium enolate of acetaldehyde (CH2 = CHOLi)n(Me2O)x, n = 1-4, x = 0-4. This approach also makes it possible to investigate molecules as large as the tetrasolvated tetramers of the lithium enolate of acetaldehyde at uniform levels. Pi-interaction between Li and the enolate double bond assists in identifying the relative stabilities of isomers and the extent of solvation.

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The synthesis and characterization of enamines and enol ethers substituted in the beta position by 2-benzoxazolyl and 2-benzothiazolyl are described. The scheme involves the condensation reactions of dimethylformamide dimethyl acetal and ethyl orthoformate, respectively, with bis(2-benzoxalyl)methane and bis(2-benzothiazolyl)methane. The electron-withdrawing capacity of the heterocyclic rings has been determined by dynamic NMR and semiempirical (PM3) analyses of rotational energy barriers.