Index Catalog // ScholarsArchive@OSU

Total synthesis of phorboxazole A

Creator:: Lee, Tae Hee
Abstract:: The total synthesis of a highly potent cytotoxic marine natural product, phorboxazole A, is described. Both a palladium(II)-mediated and a palladium(II)-catalyzed intramolecular alkoxycarbonylation were used as key steps for the preparation of the two cis-2,6-disubstituted tetrahydropyran rings (C22-C26 and C11-C15) of phorboxazole A. The synthesis used a convergent approach involving...
Resource Type:: Dissertation

Studies toward the synthesis of halichlorine and pinnaic acid

Creator:: Korf, Eric A.
Abstract:: Three approaches toward the core of halichlorine and pinnaic acid are described. The first approach entails a racemic transannular nitrone-olefin [3+2] cycloaddition from nitrone 238. Construction of the nitrone 238 began with aldehyde 241. Another key feature in this route involved a ring-closing metathesis for the formation of a 14-membered...
Resource Type:: Dissertation

Studies towards the total synthesis of (-)-kendomycin

Creator:: Smits, Helmars
Abstract:: Studies towards the total synthesis of (−)-kendomycin (1), a bacterial metabolite with a unique molecular architecture and pronounced biological activity, are described. These studies resulted in the synthesis of advanced intermediate 208, containing all of the carbon atoms of 1. A Dötz annulation between alkyne 122 and novel chromium carbenoid...
Resource Type:: Dissertation

Studies toward the total synthesis of alkaloids : nagelamide A and D, agelastatin D, dragmacidin A-C, salacin and almazoles

Creator:: Tonsiengsom, Sorasaree
Abstract:: Studies toward the total syntheses of highly potent cytotoxic alkaloids including the bromopyrrole alkaloids and indole alkaloids were conducted and are described. Studies carried out in the course of this dissertation consist of five total syntheses of natural products that include bromopyrrole alkaloids nagelamide A, D and agelastatin D as...
Resource Type:: Dissertation

Polarization spectroscopy and photodissociation studies of nitroaromatic compounds in the gas phase

Creator:: Abbott, James E.
Abstract:: The central purpose of this dissertation was to explore and expand the use of an uniform electric field for orientation and for subsequent spectroscopic investigation of asymmetric polar molecules in the gas phase. The systems of study were nitrobenzene (NB) and the nitrotoluene (NT) isomers. We were able to quantitatively...
Resource Type:: Dissertation

Tracking semi-volatile organic pollutants in remote lake systems

Creator:: Usenko, Sascha
Abstract:: SOCs volatility and persistence properties cause many SOCs to become ubiquitous in the environment as well as accumulate in areas with lower temperatures such as polar or orographic regions. Many anthropogenic SOCs pose a serious risk to human and ecosystem health because of their persistent, bioaccumulative, and toxic properties in...
Resource Type:: Dissertation

Semi-volatile fluorinated organic compounds in Asian and Pacific Northwestern U.S. air masses

Creator:: Piekarz, Arkadiusz M.
Abstract:: Current studies suggest that perfluorinated organic compounds, such as fluorotelomer alcohols (FtOHs) in the troposphere, may be precursors of perfluorocarboxylic acids and perfluorosulfonates in remote regions. Fluorinated organic compounds were investigated in archived extracts collected from remote locations in Okinawa, Japan (HSO) and Mount Bachelor, Oregon (MBO) during the springs...
Resource Type:: Masters Thesis

Analysis of semi-volatile organic contaminants and their accumulation in remote aquatic ecosystems of the western US

Creator:: Ackerman, Luke K.
Abstract:: Many pesticides, polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and polycyclic aromatic hydrocarbons are persistent, bio-accumulative, and toxic. These semi-volatile organic compounds (SOCs) can undergo atmospheric transport and deposition in cold, remote ecosystems. A better understanding of their accumulation in the fish of these ecosystems is important to better predict...
Resource Type:: Dissertation

Determination of fluorochemicals in waste-dominated aqueous systems

Creator:: Huset, Carin A.
Abstract:: While fluorochemicals have been detected all over the world and in wastewater treatment plants, the effect of wastewater effluent on the receiving waters has not been evaluated. In the first study, the mass flow of fluorochemicals emanating from wastewater treatment plants along the Glatt River in Switzerland was evaluated. The...
Resource Type:: Dissertation

Development, validation and the application of a congener specific photodegradation model for PBDEs

Creator:: Zeng, Xia
Abstract:: The thermodynamic properties of 39 PBDEs have been calculated using Gaussian 03 on the B3LYP/6-31G(d)//B3LYP/6-31G(d) level. The PBDE congeners' enthalpies of formation increase with increasing number of bromines and show a strong dependence on the bromine substitution pattern. The effects of bromine substitution pattern have been quantitatively studied by GAM...
Resource Type:: Dissertation

Solution deposition and characterization of the thin film inorganic materials

Creator:: Özmen, Bahar
Abstract:: The general emphasis of this work has been synthesis, characterization, and applications of n- and p-type inorganic oxide thin films that are deposited from solutions. In particular, a study of n-type transparent semiconductor films of tin (IV) oxide and zinc-doped tin (IV) oxide has been performed by spin coating. Solution...
Resource Type:: Masters Thesis

From electrophoresis to dielectrophoresis: designing, fabricating, and evaluating an electroformed ratchet type microfluidic dielectrophoresis device

Creator:: Gonzalez, Carlos F.
Abstract:: Dielectrophoresis (DEP) is a separation method in which a non-uniform electric field is used to induce a dipole moment in a suspended particle. If the polarization of the particle is greater than that of the suspending medium, the particle will move towards the region of higher field strength (positive DEP);...
Resource Type:: Dissertation

Trans-Pacific and regional atmospheric transport of anthropogenic semivolatile organic compounds in the western U.S.

Creator:: Primbs, Toby
Abstract:: The atmospheric transport of anthropogenic semivolatile organic compounds (SOCs) from Asian sources to the Western U.S. was investigated. In addition, the SOC extraction method was optimized. Hansen solubility parameter plots were used to aid in the pressurized liquid extraction (PLE) solvent selection of air sampling media in order to minimize...
Resource Type:: Dissertation

Graphite intercalation compounds containing fluoroanions

Creator:: Katinonkul, Watcharee
Abstract:: New chemical synthesis strategies have been investigated for the preparation of acceptor-type graphite intercalation compounds (GIC's) with fluoroanions in order to obtain new materials and to develop a better understanding of the synthetic approaches and properties of the products. New GIC's containing borate chelate anion such as bis(oxalato)borate, CxB[OC(O)C(O)O]₂•δF, are...
Resource Type:: Dissertation

Studying fusion reactions for effect of PCN on heavy nucleus formation and for nuclear structure effects

Creator:: Naik, Radhika
Abstract:: The fusion reaction ²⁰⁸Pb (⁵⁰Ti, xn) ²⁵⁸⁻x Rf (x = 1-3) was studied to determine PCN (probability that the mononucleus system evolves to form a compound nucleus inside the fission saddle point) and to establish the value of Wsur (survival probability) for the given reaction experimentally. The fission excitation function...
Resource Type:: Dissertation

Gas-phase fragmentation chemistry of protonated peptide ions

Creator:: Bythell, Benjamin James
Abstract:: The fragmentation characteristics of protonated peptides have been investigated using tandem mass spectrometry (MS/MS) under various fragmentation regimes and detailed density functional theory (DFT) reaction pathway calculations. The DFT calculations predict novel salt-bridge stabilized transition structures as well as consecutive reactions occurring in proton-bound dimers for some of the ions...
Resource Type:: Dissertation

Wide band gap semiconductors and insulators : synthesis, processing and characterization

Creator:: Hersh, Peter A.
Abstract:: The work presented here is focused on applying basic principles of solid-state chemistry to the study and development of new wide band-gap semiconductors and insulators for photovoltaic and electronic-device applications. Analysis of crystal structure, band structure, optical band gap, morphology and transport properties provides fundamental insight into materials performance as...
Resource Type:: Dissertation

Comparison between lichen, conifer needles, resin-based passive air sampling devices (PASDs), and snow to monitor semi-volatile organic compounds (SOCs) in the atmosphere

Creator:: Schrlau, Jill E.
Abstract:: The purpose of this research was to compare four different media that were used to monitor SOC atmospheric concentrations in remote ecosystems. The accumulation of semi-volatile organic compounds, including pesticides, polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs), was investigated in lichen, 2-year old conifer needles, resin-based passive air sampling...
Resource Type:: Masters Thesis

Quantitative determination of emerging contaminants, solvent stabilizers and fullerene nanomaterials, in biological and environmental systems

Creator:: Isaacson, Carl W.
Abstract:: To determine the impact of emerging environmental contaminants on human and environmental health, quantitative analytical methods are required. Analysis of emerging contaminants is hampered by their widely varying physical-chemical properties. Therefore quantitative analytical methods must be developed to determine the behavior of emerging contaminants in environmental systems. A quantitative analytical...
Resource Type:: Dissertation

High quantum-yield phosphors via quantum splitting and upconversion

Creator:: Jeong, Joayoung
Abstract:: The Gd3+ ion has been used to induce quantum splitting in luminescent materials by using cross-relaxation energy transfer (CRET). In Nd:LiGdF4, quantum splitting results from a two-step CRET between Gd3+ and Nd3+, first involving a transition 6G→6I on Gd3+ and an excitation within the 4f3 configuration of Nd3+ followed by...
Resource Type:: Dissertation

Design, fabrication and application of a microfluidic nanofiltration module for separation and purification of macromolecules and nanoparticles

Creator:: Rundel, Jack T.
Abstract:: A microfluidic nanofiltration module has been designed, fabricated and applied to the continuous-flow, pressure-driven, post-synthetic purification of macromolecules and nanoparticles via diafiltration using a commercially available organic solvent resistant nanofiltration membrane, STARMEM 122. This module will readily interface with other microscale components within a "nanofactory" for the rapid synthesis, purification...
Resource Type:: Dissertation

Design, characterization, and application of spectrometers for determination of low-level dissolved oxygen with small-volume sampling methodology

Creator:: Cakin, Defne
Abstract:: New analytical methods and instrumentation were developed for the determination of dissolved oxygen (DO) at low concentrations in water. The methods were based on monitoring the absorbance increase due to the oxidation of reduced indigo carmine (IC) by oxygen in the sample in different types of spectrometer cells. Spectrophotometer cells...
Resource Type:: Dissertation

Luminescent sulfides and solution-deposited oxide thin films

Creator:: Anderson, Jeremy T.
Abstract:: Solid state luminescent sulfides are prepared as powders in order to elucidate the relationship between structure and light emission. While the sulfides studied in this dissertation are known phosphors, materials are investigated in a variety of new ways. Elementary properties and structures of MgS are reviewed, and preparation of MgS...
Resource Type:: Dissertation

Synthesis and characterization of novel stationary phases for small scale liquid chromatographic separations of proteins and nanoparticles

Creator:: Hutanu, Daniela
Abstract:: The emerging field of nanotechnology strictly requires the micro-scaling of the available separation technology and the design of novel devices for separations of molecules of interest. The separation of proteins and nanoparticles is challenging due to their relatively large size, non-specific adherence to surfaces and instability in many solvents. This...
Resource Type:: Dissertation

A Diels-Alder approach to biaryl synthesis

Creator:: Ashburn, Bradley O.
Abstract:: An expedient approach to the synthesis of a wide range of highly programmable biaryl templates has been accomplished. Utilizing the Diels-Alder [4+2] cycloaddition, a wide range of tri- and tetra-ortho-substituted biaryls have been synthesized in only three to four steps from commercially available materials. We have successfully synthesized entire classes...
Resource Type:: Dissertation

Atropisomeric 8,8'-biquinolyl derivatives : synthesis, properties and applications

Creator:: Milicevic, Selena D.
Abstract:: 7,7'-Dihydroxy-8,8'-biquinolyl (azaBINOL) was prepared from 7-hydroxyquinoline via N,N-dimethyl O-quinol-7-yl carbamate by directed ortho-metallation followed by FeCl₃-mediated oxidative coupling of the 8-lithioquinoline intermediate. Saponification of the resulting dicarbamate provided crystalline (±)-azaBINOL in 56% overall yield. 6,6'-Bis(dimethylaminocarbonyl)-7,7'-dihydroxy-8,8´-biquinolyl was prepared from the same dicarbamate by a double anionic-Fries rearrangement in 43% yield. 7,7'-Bis(diethylamino-carbonyloxy)-6,6'-diiodo-8,8´-biquinolyl...
Resource Type:: Dissertation

Broadening the scope of the modified-Julia reaction : a mild and stereoselective method for the synthesis of (Z)-configurated α,β-unsaturated lactones

Creator:: Giesbrecht, Heath Eugene
Abstract:: An intramolecular variant of the modified-Julia olefination was demonstrated by the synthesis of α,β-unsaturated lactones in a mild and (Z)-selective fashion. The lynchpin reagent (benzothiazol-2-sulfonyl) acetic acid was synthesized in a straightforward fashion in 86% overall yield from commercially available 2-mercaptobenzothiazole via conversion to ethyl (benzothiazol-2-ylthio)acetate by base mediated alkylation...
Resource Type:: Masters Thesis

Large volume (1,800 µL) injection HPLC/MS/MS for the quantitative determination of illicit drugs and human urinary biomarkers in municipal wastewater

Creator:: Chiaia Hernandez, Aurea C.
Abstract:: A sensitive, selective, rapid analytical method based on large-volume injection (LVI) liquid chromatography/ tandem mass spectrometry was developed using commercially-available hardware that eliminates the need for either off-line or on-line solid phase extraction. Centrifugation followed by the direct injection of 1,800 µL was used for the quantification of illicit drugs,...
Resource Type:: Masters Thesis

Aqueous chemistries for oxide electronics

Creator:: Meyers, Stephen T.
Abstract:: The variegated aqueous chemistries of metal cations are applied to the design and synthesis of non-toxic solution precursors suitable for additive printing of large-area oxide electronics. Polycondensation behaviors of aqueous Al+3 and PO4 +3 are manipulated in the deposition of atomically smooth amorphous aluminum oxide phosphate (AlPO) dielectric films. AlPO...
Resource Type:: Dissertation

Semi-volatile organic compounds as molecular markers for atmospheric and ecosystem transport

Creator:: Genualdi, Susan A.
Abstract:: The use of semi-volatile organic compounds (SOCs) as molecular markers to identify the contributions of regional and long-range atmospheric transport, as well as current and historic sources, and contaminant deposition in remote ecosystems of the Western U.S. was investigated. Trans-Pacific air masses influenced by Siberian biomass burning events had elevated...
Resource Type:: Dissertation

Direct patterning of solution deposited metal oxides

Creator:: Stowers, Jason K.
Abstract:: Patterning of metal oxides typically involves a multi step process, involving depositing a resist, patterning that resist with some form of lithography, etching the oxide through the resist, and finally removing. This process can be simplified if the resist is removed and replaced with a metal oxide that can be...
Resource Type:: Dissertation

Growth and characterization of wide–gap semiconducting oxide and chalcogenide thin films by pulsed laser deposition

Creator:: Newhouse, Paul F.
Abstract:: The preparation and characterization of thin film oxides and chalcogenides by pulsed laser deposition (PLD) is presented. An overview of fundamental PLD concepts are presented and are followed by a description implementation and development of the PLD systems at OSU. We present the results of thin film growth of high...
Resource Type:: Dissertation

Catalytic desymmetrization of D₂d̳-symmertic proprochiral tetrasubstituted biphenyl compounds: a novel approach to the synthesis of axially chiral C₂-symmetric molecules

Creator:: Gunderson, Jeremey Tyson
Abstract:: Many D2d-symmetric 2,2',6,6'-tetrasubstituted biphenyls are readily prepared via net oxidative dimerization of appropriate 1,3-disubstituted benzenes. Conversion of such proprochiral compounds to useful C2-symmetric chiral biphenyls requires formal replacement of two substituents on opposing aryl ring units with alternate groups. This under exploited desymmetrization tactic has been demonstrated for the generation...
Resource Type:: Masters Thesis

Fabrication and application of polymer based microfluidic devices

Creator:: Koesdjojo, Myra T.
Abstract:: The concept of reducing laboratory operations in scale such that they fit on a microfluidic chip has been met with great enthusiasm. Lab-on-a-chip devices promise to be cost effective to operate due to reduced reagent consumption, have the potential to offer shorter analysis times due to their short path lengths,...
Resource Type:: Dissertation

Total synthesis of sparteine alkaloids from a common tetraoxobispidine intermediate

Creator:: Melbardis, John
Abstract:: In previous work (Blakemore et al. Org. Lett. 2005, 7, 4721; Heterocycles 2006, 70, 609), successful elaborations of the lupine alkaloids (±)-α-isosparteine (dl-2) and (±)-β-isosparteine (dl-3) were realized from a common tetraoxobispidine precursor, 3,7-diallyl -2,4,6,8-tetraoxo-3,7-diazabicyclo[3.3.1]nonane (93). Herein, the tetraoxobispidine approach to lupine alkaloids was extended to a total synthesis of...
Resource Type:: Masters Thesis

Galvanostatic control of ion selective electrodes with the solvent polymeric membrane

Creator:: Perera, Hasini R.
Abstract:: Detection technique that proposed utilizing electrochemically controlled, reversible ion extraction into polymeric membrane in an alternating galvanostatic/ potentiostatic mode was introduced. This method is studied in detail to comprehend the advantages of the novel sensor (pulstrode) compared to the potentiometric ion selective electrode (ISE), studies included possible applications and limitations....
Resource Type:: Dissertation

Polyion sensors based on induced ion extraction

Creator:: Fordyce, Katherine
Abstract:: A novel method for detecting the peptidase activity of clinically relevant peptidases was investigated using solid-contact electrochemical polyion sensors under chronopotentiometric control. Complete instrumental control over ion-extraction was accomplished by incorporating a lipophilic electrolyte into the ion-selective membrane; the sensors had no intrinsic ion-exchange capabilities. The sensors were used to...
Resource Type:: Masters Thesis

Determination of ethyl glucuronide and ethyl sulfate as human biomarkers of alcohol exposure in urine by liquid chromatography/electrospray tandem mass spectrometry with large volume injection

Creator:: Hu, Yan
Abstract:: This research was undertaken to develop a sensitive, selective, and rapid analytical method to measure ethyl glucuronide (EtG) and ethyl sulfate (EtS) in urine as urinary biomarkers of alcohol exposure. Large-volume injection (LVI) coupled with liquid chromatography / electrospray tandem mass spectrometry was used to eliminate the need for either...
Resource Type:: Masters Thesis

Expanding the scope of a Diels-Alder approach to biaryl synthesis

Creator:: Schwartz, Johanna Perkins
Abstract:: A Diels-Alder approach to biaryls (DAB) has been applied towards the synthesis of highly substituted, programmable biaryl templates. Tri- and tetra-ortho-substituted biaryls can be produced in just three to four steps from commercially available materials utilizing the Diels-Alder [4+2] cycloaddition. The methods described herein will illustrate the ability of mono...
Resource Type:: Dissertation

Micro total analysis system for in-situ and autonomous spectrophotometric monitoring of iron in groundwater

Creator:: Koch, Corey R.
Abstract:: We have developed a compact micro total analysis system (μTAS) to serve as a platform for in-situ spectrophotometric water quality monitoring. Individual fluidic, optical, and electrical components were designed, developed, and characterized. These components were combined in both an integrated (single lithographic “chip-based” platform) and a modular manner. The microfluidic...
Resource Type:: Dissertation

Part I: Synthetic studies toward the southern portion of Azaspiracid-1; Part II: Total synthesis of amphidinolide B₁ and the proposed structure of amphidinolide B₂

Creator:: Lu, Liang
Abstract:: The structural architecture present in marine toxin azaspiracid - 20 stereocenters, 9 rings, 3 separated spirocenters - has attracted considerable synthetic attention. Our efforts toward the synthesis of azaspiracid have led to the completion of both C₁-C₂₆ northern and C₂₇-C₄₀ southern halves. Herein, the synthesis of southern FGHI ring system...
Resource Type:: Dissertation

The transient electric birefringence of nanomaterials: alignment mechanism, characterization, and its application towards aligned polymer nanocomposites

Creator:: Teters, Chad N.
Abstract:: The experimental and theoretical bases of transient electric birefringence (TEB) and its application in a variety of nanomaterials, including Na-montmorillonite, cellulose nanocrystals (CNXL), and CdSe quantum dots (QDs) will be presented. TEB is a phenomenon attributed to the alignment of particles in response to an applied electric field and has...
Resource Type:: Dissertation

Studies towards the total syntheses of (+)-phomactins A, D and G

Creator:: Schwartz, Keith D.
Abstract:: Studies towards the total synthesis of (+)-Phomactin A (1), D (6), and G (9), fungal metabolites with unique molecular architecture and pronounced biological activity, are described. These studies resulted in the synthesis of advanced intermediates 354 and 356, which contain all of the carbon atoms of 1, 6 and 9....
Resource Type:: Dissertation

Tandem mass spectrometric analysis of protein and peptide adducts of lipid peroxidation-derived aldehydes

Creator:: Wu, Jianyong
Abstract:: The adduction of proteins and other biomolecules by electrophilic lipid peroxidation products such as 4-hydroxy-2-nonenal (HNE), 4-oxo-2-nonenal (ONE), malondialdehyde (MDA) or acrolein (ACR) is thought to be an initiating and/or propagating factor in the pathophysiology of several diseases such as atherosclerosis, diabetes, Alzheimer's, Parkinson's and other age-related disorders. The identification...
Resource Type:: Dissertation

Mass spectrometry-based identification and characterization of protein and peptide adducts of lipoxidation-derived aldehydes

Creator:: Chavez, Juan D.
Abstract:: Oxidative stress is recognized as an important underlying factor in the pathogenesis of many degenerative diseases as well as normal senescence. The free radicals, reactive oxygen species (ROS) and electrophiles produced during oxidative stress are capable of modifying nucleic acids, lipids and proteins. There are a variety of oxidative modifications...
Resource Type:: Dissertation

Development of organocatalyzed, intramolecular heteroatom Michael addition and application towards alkaloid synthesis

Creator:: Carlson, Erik
Abstract:: Effective methods for the enantiopure formation of substituted piperidine rings are significantly important due to their presence in alkaloid products. A valuable method to form these ring systems would be via an intramolecular heteroatom Michael addition from the corresponding enone or enal. Described herein is a methodolgy that has been...
Resource Type:: Masters Thesis

Magnetic particles for selective extraction of trace analytes in microfluidic devices

Creator:: Tennico, Yolanda H.
Abstract:: The development of micro total analysis systems (µTAS), also called “lab-on-a-chip”, or microfluidic analysis systems, is presented in this dissertation. Various research areas, covering subjects from magnetic particles synthesis to novel microchip fabrication techniques, are explored to develop a lab-on-a-chip system capable of performing magnetic bead-based bioassays. These devices are...
Resource Type:: Dissertation

Copper and iron chalcogenides for efficient solar absorption

Creator:: Platt, Heather A. S.
Abstract:: This dissertation outlines two approaches for improving the efficiency and reducing the cost of photovoltaic energy generation. First, the structures of known binary copper and iron compounds are used to choose the promising compositions Fe₂XS₄ (X = Si, Ge), Cu₃TaQ₄ (Q = Se, Te), and BaCuQ'F (Q' = S, Se,...
Resource Type:: Dissertation

New luminescent materials and high-performance solution-processed oxide thin films

Creator:: Jiang, Kai
Abstract:: Crystals of an incongruent-melting compound, Ba₃MgSi₂O₈, were grown by the flux method and its structure was determined by single crystal X-ray diffraction methods. Ba₃MgSi₂O₈ crystallizes in trigonal space group P-3[bar]m1 with a = 5.6123(3) Å, c = 7.2667(9) Å and Z = 1. Eu²⁺ ions prefer one crystallographic Ba site...
Resource Type:: Dissertation

Functional transition metal oxides : structure-property relationships

Creator:: Smith, Andrew E.
Abstract:: Transition metal oxides are an important class of materials for the wide variety optical, electrical, dielectric, magnetic, and thermal properties observed. Their unique structure-property relationships allow for property tuning and often provide insight into the fundamentals of chemistry. The work in this thesis was focused on the design, synthesis and...
Resource Type:: Dissertation

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