Article describes the main surface activation and pretreatment techniques for substrates such as titanium and its alloys, stainless steel, magnesium alloys, and CoCrMo alloys.

This article presents theoretical and experimental results for the surface core-level binding energy, BE, shifts, SCLS, for MgO(100) and the anomalous O(1s) SCLS is interpreted in terms of the surface electronic structure.

Article on the surface tension calculation of mixed solvents with respect to solvent composition and temperature by using Jouyban-Acree model.

Article describes how symmetry breaking charge transfer is one of the important photo-events occurring in photosynthetic reaction centers that is responsible for initiating electron transfer leading to a long-lived charge-separated state and has been successfully employed in light-to-electricity converting optoelectronic devices. In this study, the authors report a newly synthesized, far-red absorbing and emitting BODIPY-dimer to undergo symmetry-breaking charge transfer leading to charge-separated states of appreciable lifetimes in polar solvents.

Article discussing the synergy between qualitative theory, quantitative calculations, and direct experiments in understanding, calculating, and measuring the energy differences between the lowest singlet and triplet states of organic diradicals.

This article reports the synthesis, characterization, and solution dynamics of the novel nickel(II) complexes (dimethylbis(2-pyridyl)borate)(triphenylphosphine)nickel(II) chloride (4) and (dimethylbis(2-pyridyl)borate)nickel(II) acetylacetonate (6).

Presentation for the 2006 University Scholars Day at the University of North Texas discussing the synthesis and characterization of nickel and nickel hydroxide nanopowders.

This dissertation is a study of two major topics that involve synthetic strategies for new classes of phosphorescent gold(I)-based metallodendrimers. The phosphorescence of organic and inorganic luminophores originates from spin-orbit coupling owing to internal or external heavy atom effects as well as metal-centered emissions. Previous work in the Omary group entailed systematically designed small molecules, metallopolymers, and unconjugated metallodendrimers that contain d10 and d8 metals, whereas this dissertation aims in part to expand such strategies to the conjugated metallodendrimer regime. In one approach novel synthetic strategies were used to make first-generation phenyl acetylene dendrimers and phosphine derivatives thereof. The phosphine dendrimers are made by tethering one of the phosphines to an unsaturated dendrimer, as such phosphine dendrimers are better chromophores and luminophores due to their structural rigidity and extended conjugation. In another approach, 2- and 3-coordinate Au(I) dendritic complexes are synthesized from these phosphine dendrimers. This study is further extended to study metallodendritic complexes with different cores, for example triphenylene-based metallodendritic complexes with six acetylene branches. The physical properties of the metallodendrimers can be modulated upon proceeding to further dendrimer generations or by using solubilizing groups on the peripheral phosphines, thus allowing better processability for thin-film fabrication as required for …

Article discussing the synthesis and reactivity of a coordinatively unsaturated Ruthenium(II) parent amido complex and studies of X-H activation (X = H or C).

This dissertation reports the preparation of several types of anthraquinones structurally related to adriamycin. It describes the synthesis of two types of 2-aminoquinizarin compounds. It also presents two new syntheses of a heterocyclic tetracyclic ring system, similar to the aglicone ring system of adriamycin. A series of 2-aminoquinizarins was prepared by adding several primary amines to quinizarin. Quinizarin was shown to be essentially inert toward secondary amines. Several secondary amine adducts with quinizarin have been prepared, however, by treating the bis-boroacetate ester of quinizarin with the amines. Both types of 2-aminoquinizarin compounds exhibit outstanding potential for possessing antineoplastic activity, and several have been submitted to the National Cancer Institute for testing in their screening program for antineoplastic agents.

Ketene dimethyl thioacetal monosulfoxide was prepared in 68% overall yield in two steps starting from methylmagnesium chloride. The yield of dithioacetic acid was improved significantly by employing tetrahydrofuran as solvent and using elevated temperatures. A one-pot synthesis of ketene thioacetals from alkyl halides was developed and several ketene thioacetals were prepared by this method. Direct oxidation of ketene thioacetals using m-chloroperoxybenzoic acid provided a general route to ketene thioacetal monosulfoxides. In cases where E and Z isomeric ketene thioacetal monosulfoxides were possible, the E/Z isomeric ratio increased as the substituents on the ketene double bond was increased in size.

This article presents a simple, inexpensive, and efficient chemical method of synthesizing nickel and nickel hydroxide powders with nanometer-sized particles.

Article discussing the synthesis of the five-coordinate ruthenium (II) complexes and reactions with phenyldiazomethane and phenylacetylene.

The reaction of 2-[(diphenylphosphino)methyl]-6-methylpyridine (PN) with Os3(CO)12-n(MeCN)n [where n = 0 (1), 1 (2), 2 (3)] has been investigated. Os3(CO)12 reacts with PN in the presence of Me3NO to afford the clusters Os3(CO)11(1-PN) (4) and 1,2-Os3(CO)10(1-PN)2 (5). X-ray diffraction analyses confirm the equatorial coordination of the phosphine(s) in 4 and 5, with the two phosphines in the latter cluster exhibiting a 1,2-trans orientation about the Os-Os vector that contains the two ligands. Treatment of the MeCN-substituted cluster Os3(CO)11(MeCN) and PN (1:1 ratio) in CH2Cl2 gives clusters 4 and 5, in addition to HOs3(η1-Cl)(CO)10(1-PN) (6) as a result of competitive activation of the reaction solvent. Cluster 6 contains 48e- and the diffraction structure reveals the presence of axial chloride and equatorial phosphine ligands which are located on adjacent osmium atoms. The bridging hydride ligand in 6 spans the Cl,P-substituted Os-Os vector. The reaction of Os3(CO)10(MeCN)2 with PN furnishes 5, 6, and 1,1-Os3(CO)10(2-PN) (7) in yields that are dependent on the reagent stoichiometry and reaction solvent. The solid-state structure of 7 confirms the chelation of the PN ligand to a single osmium atom via the pyridine and phosphine moieties at axial and equatorial sites, respectively. The bonding in 7 relative to other …

The objective of this study was to develop new synthetical routes to natural and industrial products utilizing ketene cycioaddition reactions. The cycioaddition of diphenylketene with α,β-unsaturated imines yields (2+2) cycioaddition products, g-lactams. However, electron donating groups, such as dimethylamine, in the 4-position of the α,β-unsaturated imines result in (4+2) cycloaddition products, ∂-lactams. Dichloroketene reacted with α,β-unsaturated imines to yield (4+2) cycloaddition products, g-lactams. Large substituents in the 4-position of a, ^-unsaturated imines resulted in a (2+2) cycioaddition product, β-lactam. The ∂-lactams derived from dichloroketene are easily dehydrochlorinated to the corresponding 2-pyridornes.

Article discussing synthetic approaches to (smif)₂Ti(smif=1,3-di-(2-pyridyl)-2-azallyl) revealing redox non-innocence and C-C bond-formation.

This article discusses a T-shaped three-coordinate nickel(l) carbonyl complex and the geometric preferences of three-coordinate d9 complexes.

Polymeric nanoparticles were designed, synthesized, and loaded with metal ions to explore the therapeutic potential for transition metals other than platinum found in cisplatin. Nanoparticles were synthesized to show the potential for polymer based vectors. Metal loading and release were characterized via Inductively Coupled Plasma Mass Spectrometry (ICP MS), Energy Dispersive X-Ray Spectroscopy (EDX), X-Ray Photoelectron Spectroscopy (XPS), and Elemental Analysis. Targeting was attempted with the expectation of observed increased particle uptake by cancer cells with flow cytometry and fluorescence microscopy. Results demonstrated that a variety of metals could be loaded to the nano-sized carriers in an aqueous environment, and that the release was pH-dependent. Expected increased targeting was inconsistent. The toxicity of these particles was measured in cancer cells where significant toxicity was observed in vitro via dosing of high copper-loaded nanoparticles and slight toxicity was observed in ruthenium-loaded nanoparticles. No significant toxicity was observed in cells dosed with metal-free nanoparticles. Future research will focus on ruthenium loaded polymeric nanoparticles with different targeting ligands dosed to different cell lines for the aim of increased uptake and decreased cancer cell viability.

Presentation for the 2010 University Scholars Day at the University of North Texas discussing teaching students organic chemistry and a QEP III Next Generation course redesign.

This paper discusses research on teaching students organic chemistry and a QEP III Next Generation (N-Gen) Course Redesign project.

Article on temperature and pressure dependence of the reaction S + CS (+M) → CS2 (+M).

Article on temperature dependence of the absolute third-order rate constant for the reaction between Na + O₂ + N₂ over the range 571-1016 K studied by time-resolved atomic resonance absorption spectroscopy.

Authors of the article assert that rate coefficients, k1(T), for the gas-phase reaction of the OH radical with Furan-2,5-dione (maleic anhydride (MA), C4H2O3), a biomass burning related compound, were measured under pseudo first-order conditions in OH using the pulsed laser photolysis - laser induced fluorescence method over a range of temperature and bath gas pressure. Their results are compared with a previous room temperature relative rate study of the OH + MA reaction and significant discrepancy between the studies is discussed. This is the accepted manuscript version of the published article.

Dataset generated for research on test and training bio systems.