Metabolomics has recently gained momentum in biomolecule research and complements the genomics and proteomics research space. Metabolomics strives to detect, identify, and quantify all metabolites present in biological samples. In particular, biomolecular analysis using ultra-performance liquid chromatography combined with mass spectrometry (UPLC-MS) has become increasingly important for metabolomic analyses. Similarly,...
The continued long-term use of fossil fuels as a primary energy source has resulted in dramatic increases in greenhouse gas emissions and the associated concerns of climate change and environmental pollution. A key strategy to circumvent these issues is a global shift away from fossil fuels toward renewable energy sources....
In this dissertation, the primary objective is to discover more sustainable electrode materials and study new reaction mechanisms using aqueous electrolytes. The first study conducted reveals a reversible conversion reaction from copper to Cu2CO3(OH)2. The reaction mechanism uses OH- and CO32- as charge carriers at the cathode. The results open...
The concept of reducing laboratory operations into microfluidic devices has been an attractive area of research for several decades. Due to several advantages of porous-media microfluidic devices including low mass, portability, power-free fluid transport, and the ability to store dried reagents in the porous structures, these devices show great promise...
Per- and polyfluoroalkyl substances (PFAS) are a group of anthropogenic compounds that are used ubiquitously in different industrial fields. However, concerns regarding the potential health impacts of PFAS, including perfluoroalkyl carboxylic acids
(PFCAs) and perfluoroalkyl sulfonates (PFSAs), has raised stakeholder interest regarding continued use of PFAS. Analytical methods for PFAS...
Aromatic heterocycles are core structural motifs in natural products, pharmaceuticals and biological polymers. Indoles, in particular, represent a significant subclass of aromatic heterocycles, both in terms of sheer numbers, but also in biological and pharmaceutical relevance. As such, new methodologies for the synthesis of indoles represent an important and continually...
Put generally, the work I have conducted in my time at Oregon State University has been to answer two questions. The first of these is “Why do I get this particular product from this particular chemical reaction?” and the second is “How do the reagents in this chemical reaction lead...
The first part of this manuscript is about the total synthesis of the aspidosperma alkaloids leuconoxine, melodinine E and mersicarpine. Our synthetic strategy used a radical translocation-conjugate addition cascade to construct the core of the natural product. Specifically, a vinyl radical was generated from the homolysis of the C–I bond...
The bimolecular reaction of two carbenoid species resulting in the formation of a carbon-carbon double bond (pi-system), referred to herein as carbenoid eliminative cross-coupling (CEXC), involves a series of three fundamental steps: (i) ate-complex formation (transmetalation), (ii) 1,2-metalate rearrangement, and (iii) beta-elimination. All three steps are stereospecific and so the...
Ultrafast spectroscopy has recently gained momentum as a powerful, noninvasive characterization toolset capable of studying a diverse array of samples with applications in chemistry, physics, biology, engineering, and more. Two popular ultrafast spectroscopic techniques include femtosecond transient absorption (fs-TA) and femtosecond stimulated Raman spectroscopy (FSRS). The latter of these techniques...
My work has focused on using density functional theory to elucidate mechanisms of organocatalytic and transition metal catalyzed reactions by considering competing mechanisms. In each of the three presented studies computational investigation complemented experimental work by predicting stereoselectivity or revealing origins of stereo, regio, or chemoselectivity.
A study on the...
Metal-oxo clusters can be described as soluble pieces of metal-oxide frameworks. Metal-oxo clusters are also the building blocks for the Metal-Organic Frameworks (MOFs) and coordination polymers. A better knowledge of metal-oxo clusters helps fundamentally understand geosciences, molecular engineering, catalysis, single-molecule magnetism, and MOFs for synthesis, design, and modification of these...
The general theme of this dissertation is the development of new analytical sensors to quantitatively study biological and environmental samples in aqueous and non-aqueous environments. A platinum ultramicroelectrode (UME) and a unique carbon-based pH microprobe were used to design a new SECM-based electrochemical bioassay. The Pt UME was used to...
In this dissertation, I present experimental observations of multiply charged atomic ions (MCAI) generated from interactions of atomic/molecular clusters with moderately intense nanosecond laser pulses. This process is also known as Coulomb explosion (CE) and it has been extensively studied in intense laser fields using ultrashort pulses. Several prevailing theories...
Polyoxometalates (POMs) are anions consisting of three or more early transition metals ™ (Gr V and VI) oxoanions (in their highest oxidation state) linked together by a shared oxygen bond to form a 3D framework. Polyoxometalates (POMs) are a rapidly growing class of metal oxo clusters with a wide range...
Ultrafast spectroscopy can exploit the structure-function relationship of chemical- and biological-based systems. More specifically, femtosecond stimulated Raman spectroscopy (FSRS) provides ground- and excited-state vibrational information with simultaneously high spectral (spatial) and temporal resolutions. The electronic counterpart, femtosecond transient absorption (fs-TA), complements FSRS data analysis as part of a comprehensive approach...
The presence of per- and polyfluoroalkyl substances (PFAS), organic contaminants first synthesized in the 1940s, has been reported worldwide in a variety of environmental matrices and ultimately in biological systems including humans. Ongoing research into PFAS has included identifying novel PFAS, assessing their fate and transport in the environment, and...
Substituted phenols are important substructures for pharmaceuticals, agrochemicals, natural products and biological probe molecules. The properties of phenolic molecules are substantially influenced by the substitution patterns of the phenolic ring. The chemical synthesis of phenols with various substitution patterns is an enduring challenge and multiple strategies have emerged. However, some...
A molecular approach to metal oxides allows to the study to fundamental bonding and formation behavior for such metals. Moreover, the molecular nature of such oxides or metal-oxo clusters allows the possibility of exploitation of the properties of the parent oxides. The tetravalent metals, in specific, (M=Zr, Hf, Ce, Th,...
In this dissertation, I describe the experimental investigation of electron diffraction of neutral and ionic clusters doped into superfluid helium droplets. The project is aimed at contributing to the development of an overall approach called ‘serial single molecule electron diffraction imaging (ss-EDI), a potential approach to solve macromolecule structures bypassing...
The grand plan of carbon neutralization and COP26 in Glasgow require a quick shift of energy sources from conventional fossil fuel to a more renewable substitute such as wind, or solar energy. However, the intermittency of those renewable energy sources does not meet the demand of the energy, which requires...
The increase in the demand for energy is estimated to be 28 TW by a year of 2050, which is twice of the energy produced in 2010, in response to the unprecedented growth of the global population. Current energy market is heavily relying on the fossil fuel, which brings the...
Chalaniline A, an unusual xanthone-like aminofulvene with modest cytotoxicity, and chalaniline B [1-anilino-2,8-dihydroxy-3-(hydroxymethyl)xanthone], an antibacterial aminoxanthone, were previously isolated by Loesgen and coworkers from vorinostat-treated Chalara sp. 6661. Of note, the anilino moiety found within both chalaniline structures originates from biotransformation of the HDAC inhibitor vorinostat (SAHA, suberanilohydroxamic acid) by...
The demand for the development of sustainable energy is an all time high as we burn through limited fossil fuel reserves and as environmental concerns rise every year. Renewable energy sources such as wind and solar power have limitations due to inconsistent power supply that cannot meet the regular needs...
Per- and polyfluoroalkyl substances (PFAS) are a group of contaminants of great concern due to their toxicity and ubiquity in the environment. Remediation efforts historically have focused on granular activated carbon (GAC) because of its low maintenance and relatively low cost. However, GAC is not PFAS selective and is especially...
This dissertation presents a study of structure-property relationships within 3d/4d metal oxides containing precious metals through detailed structure refinements using high-resolution neutron and X-ray diffraction data along with exploration of the resultant properties.
Oxides of 4d or 5d transition metals tend to show new topological phases due to significant spin-orbit...
In this dissertation, a novel method for analyzing computed transition states (TS) for organic reactions is disclosed. It introduces the use of localization-delocalization matrices as parameters in a linear free energy relationship to determine the transition state interactions responsible for differences in energy between the major and minor TS in...
Naturally occurring assemblies, such as DNA and proteins, utilize intermolecular forces (i.e H-bonding and van der Waals) to assemble. Utilizing these electrostatic interactions has only just started in the past five decades to be a tool used in synthetic chemistry in what is known as supramolecular chemistry. Supramolecular chemistry has...
Metabolomics and lipidomics lay the foundation of personalized medicine. The technological advancements in mass spectrometry techniques in combination with computational algorithms and methods have enabled the study of small molecules (metabolites and lipids) for understanding the disease state and biological pathways, the identification of biomarkers and the generation of predictive...
Photoactivated biomedical tools like fluorescent biosensors and optogenetic proteins have increased in popularity due to the precision targeting and activation used for in vivo applications. In nature, the initially discovered parent proteins exhibit properties such as fluorescence quantum yield (FQY), fluorescence color, and photoswitching dynamics that are unfavorable in mammalian...
Traditional approaches for the direct preparation of alkenes are unable to fully control either the stereochemical configuration of the carbon-carbon double bond or else the regiochemistry of the substituents surrounding it. The recently introduced concept of carbenoid eliminative cross-coupling (CEXC) offers a remedy to these deficiencies by providing for a...
In this dissertation, the structural properties, thermodynamics and defect behavior of amorphous metal oxides and polyoxometalates are studied. Amorphous metal oxides have many applications, most notably as a semiconducting material used as the active matrix of thin film transistors. Alas, the amorphous nature of these materials makes studying them rather...
The total kinetic energy (TKE) in the fast neutron induced fission of 237Np was measured for neutron energies from En = 2.6 – 45.7 MeV at the LANSCE- WNR facility. The postTKE release decreases non-linearly with increasing incident neutron energy and can be represented as TKE(MeV) = (169.365 ± 1.551)...
Humanities have been craving more freedom and conveniences in whatever form. Carriages evolved to cars and ultimately to aircraft so that one can reach any place in the globe within a day. The mobile phone has enabled people to make a phone call without a need to find a phone...
This dissertation demonstrated that the electrical properties of complex oxide-based perovskite materials could be controlled through the careful modification of both material composition and structure. This was first shown through the modification of lead zirconate titanate (Pb(Zr0.52Ti0.48)O3, PZT) solid solutions with bismuth indate (BiInO3, BI) where the relative stability of...
The microbial communities play a crucial role in maintaining human health and cause diseases through very complex microbial chemical interactions. Therefore, these microbial communities have drawn much attention to the scientific communities. To elucidate these complex microbial communities and the chemical interactions within it, one or more isolated species of...
In the past decades, femtosecond stimulated Raman spectroscopy (FSRS) has been gaining tremendous popularity in fundamental sciences stemming from chemistry to biology. It is capable of capturing both equilibrium and non-equilibrium structural information across a broad range of timescales with simultaneously high temporal and spectral resolutions. Femtosecond transient absorption spectroscopy...
In the 21st century, environmental deterioration is now an indisputable fact. Reliable and economically viable electricity systems based on renewable sources are urgently needed to replace the environmentally detrimental fossil fuels. The feasibility of incorporating renewable-but-intermittent solar and wind energy heavily depends on the development of cost-effective and safe technologies,...
The work presented here is the culmination of efforts in describing complex chemical systems with statistical methods, thereby providing relatively simple quantitative models and easily comprehensible qualitative insights. The following investigations have various goals, such as development of new methods, fundamental understanding, molecular control of chemical species, and advancement of...
Uranyl peroxide clusters are the newest family of polyoxometalates, discovered in 2015. Although this family is new, over 70 topologies have been reported. However, we lack the fundamental understanding of assembly mechanisms, particularly the role of the alkali countercations. Here, we use a wide range of solution and solid-state characterization...
Novel graphite intercalation compounds (GICs) and associated chemistry have been explored, specifically: (1) containing alkyl- substituted imidazolium cations; (2) a series containing alkaline earth metal (Mg, Ca, Sr, Ba) cations with ethylenediamine (en) co-intercalates; (3) showing reversible intragallery M-M bonding and (4) via electrochemical intercalation of Mg cations with potential...
This work investigates the relationship between the local structure and physical properties of a set of classical (MgTiO3, CaTiO3, SrTiO3, and BaTiO3) and complex ((1-x)Ba(Zr0.2Ti0.8)O3-x(Ba0.7Ca0.3)TiO3[BZT-BCT], Na0.5Bi0.5TiO3 [NBT]) perovskite electroceramics. The materials in this work were synthesized via standard solid state ceramic synthesis, the structure was investigated through a number of...
Nowadays selective separation processes are sought after more than ever before. They are indispensable to meet the growing demand for individual rare earth elements, minor actinides partitioned from fission-produced lanthanides, as well as, overall, more concentrated and high-purity products. This research focuses on such separation techniques as solvent extraction which...
Understanding structural evolution in solids as composition changes is essential to materials properties prediction. Such structure-properties relationships are the theme of solid state chemistry. Materials scientists and chemists have utilized an abundance of simple crystal structures to enhance understanding of chemical and structural origins of properties in materials for decades....
The study of natural products (NPs) and their application has shaped humanity. Starting with the idea of using plants as medicine, it has now grown into the science of purifying and identifying organic molecules from nature to study their inherent biological activities. Understanding the molecular structures of NPs is the...
Solid state inorganic oxides play an important role in next generation electronics based on their stability, versatility, and enhanced properties over other materials. However, in order to design or tune these materials for a desired functionality it is necessary to fully understand the structure behind the properties exhibited. This dissertation...
Metal-oxo clusters are discrete, soluble pieces of bulk metal oxide. Cluster size, monodispersity, and chemical properties allow for potential use as solution-based precursors for functional metal oxide films. Classical monoalkyltin-oxo clusters are either charge neutral or stabilized by anions. The structure of Cs₄.₅H₂.₅[(BuSn)₃(α-SiW₉O₃₇)]*2H₂O enables its use in established ion exchange...
Per- and polyfluoroalkyl substances (PFAS) are a group of anthropogenic compounds gaining notoriety as contaminants of emerging concern. With the frequent detection of PFAS in the environment, drinking water, and consumer products, awareness and concern from the public regarding PFAS is increasing. The two most notorious PFAS are perfluorooctanoate (PFOA)...
Organotin clusters have attracted notable attention for use as inorganic photoresists. This dissertation discerns dimeric and dodecameric organotin clusters, [(n-C₄H₉Sn)(OH)(H₂O)Cl₂]₂ (Sn₂) and [(n-C₄H₉Sn)₁₂O₁₄ (OH)₆ ]+ (Sn₁₂), both of which are stable hydrolysis and condensation products of n-C₄H₉SnCl₃. This work identifies Sn₂ as a superior precursor choice for solution deposition of...
Atmospheric fine particulate matter (PM2.5) has been linked to the death of 7 million people per year around the planet. The organic portion of PM2.5 is responsible for increases in oxidative stress, inflammation, mutation and carcinogenesis. Anthropogenic activity releases more organic material into the atmosphere, and has increased the amount...
Metal-oxo clusters can be described as soluble pieces of metal-oxide frameworks. Currently, metal-oxo clusters are being considered as solution-based precursors for extreme ultraviolet (EUV, 13.5 nm) photoresist materials, which are a crucial component in the fabrication of microelectronic devices. Two different photoresist precursor systems have been investigated – alkyltin clusters...
Metal-oxo clusters are discrete molecular metal-oxides. Most metals form numerous cluster compounds that can be ligated, unligated, charged or neutral, controlling their solubility in water and/or organic solvents. They are important species to study reaction pathways from the monomeric building units to the bulk metal oxides, and have many application...
Dental plaque is one of the well-characterized biofilms in the human body. Oral bacterial species play vital roles in maintaining healthy bacterial homeostasis as well as causing oral infections. Many of the oral diseases are caused by opportunistic pathogens, and therefore, the bacterial metabolic activities become important in dictating their...
Tethering fluorophores on metal nanoparticles for metal enhanced fluorescence (MEF) has attracted a lot of attention from scientists interested in fluorescence based approaches. MEF has many benefits in fluorescence related techniques, because the analytical signal increases and enables potentially lower detection limits or better sensitivity. Many types of nanoparticles have...
Mandelalide A has attracted considerable interest from the synthetic community due to its intriguing structure and important cytotoxic activity. Madeirolide A, a structurally related macrolide, shows promising antifungal activity but no appreciable anticancer activity. This dissertation describes synthetic studies toward mandelalide A, madeirolide A and their hybrid structures.
Part I...
Analytical techniques are utilized in a wide variety of applications. Traditionally, analytical measurements are achieved by trained personnel in a laboratory setting using expensive scientific instruments, which limits their applicability in resource-limited areas and point-of-care applications. Therefore, the concept of enabling these laboratory-based qualitative and quantitative assays in microfluidic device...
My work has focused on streamlining the study of organic compound structure, properties, and reactions by 1) understanding and using available computational software, 2) developing software packages to facilitate data manipulation as well as augment public programs, and 3) applying public and in-house developed software to further the understanding of...
Dearomatization reactions exist broadly in biosynthesis and chemical synthesis. The highly functionalized atoms of arenes can be masked by it aromaticity, and upon dearomatization, those reactive atoms can be readily applied to bond formation and further manipulation. The total synthesis of (–)-cephalotaxine and (–)- homoharringtonine is described via an oxidative...
In this dissertation, I describe the experimental investigation of large superfluid helium droplets. The goal and direction of this thesis is to facilitate the use of these droplets as part of our project ss-EDI. The overall scheme of ss-EDI is to dope proteins inside helium droplets and collect a diffraction...
In this dissertation, the process of computational modeling of amorphous oxide materials is studied. Amorphous oxides have random atomic arrangements with no long-range structural order which makes it difficult to study structure-property relationships. Despite the difficulties, amorphous oxides have great uses as semiconductors and dielectrics in thin-film transistors. The ability...
This dissertation is separated into two parts according to the two major distinct research projects. In Part I, the full account of synthetic studies toward C10-functionalized lycopodium alkaloids is described. In Part II, the detailed discussion on the exploration of the Pummerer cyclization methodology and its application to the total...
Part I of this dissertation includes the chronological synthetic background of mandelalide A as well as the synthesis of the C1-C14 glycosylated southern subunit of mandelalide. A key aspect of the synthesis includes a novel silver-catalyzed cyclization (AgCC) of a propargylic benzoate to construct the substituted cis-pyran ring system present...
Small molecule drugs have been instrumental in our fight against diseases, beginning when some of the earliest ancient cultures used plant remedies to treat illnesses. More recently, the skill of isolating and characterizing the active ingredients within bioactive plants and microbial extracts has led to the isolation and design of...
Exploring bioactive natural products has contributed largely to clinically approved drugs we have been using over the last 100 years. Especially among the anti-infective drugs, around 70% of currently used antibiotics were discovered or derived from microbial secondary metabolites, among them compounds like vancomycin, chloramphenicol, and erythromycin. Facing the unavoidable...
This work investigates the effect of cation substitution on the properties of the lead-free, solid solution (Na₀.₅Bi₀.₅)TiO₃-BaTiO₃ (NBT-BT). Substitution into NBT-BT increases disorder and increases the relaxor ferroelectric properties. These relaxor ferroelectric materials show large piezoelectric strains that can be utilized in actuator applications. Ceramic samples were prepared using standard...
In this dissertation, the structure and electronic properties of multiple metal oxide thin films are characterized and presented. Prompt inorganic condensation (PIC) of metal-oxo and –hydroxo clusters was evaluated as a technique for making metal oxide clusters in two separate studies. The first focuses on the synthesis of lithium niobate...
Water is an absolute necessity for life as we know it. It provides a useful medium in which chemical reactions take place that allowed for the development of single cellular organisms. When combined with the evolutionary accident that was pho- tosynthesis, water became not only a useful medium chemical reactions,...
Structure-property relationships have always underpinned the field of solid state chemistry; dependable structural descriptions are integral to understanding and controlling the physical properties of inorganic compounds old and new. While a handful of crystal structures are celebrated for their versatility, flexibility, and functionality, the existence of more exotic structures is...
Recently researchers have discovered that groups of small non-coding RNAs (ncRNAs) play regulatory roles in gene expression and participate in various biological processes. For example, pathogenesis of many diseases, cell cycle regulation, and signaling pathways. Intracellular and live cell imaging of small ncRNA groups will reveal their relative expression levels...
Mass Spectrometry has emerged as an analytical core technique in omics sciences, in particularly mass spectrometry has advanced the fields of proteomics, metabolomics and lipidomics in recent years. Mass spectrometric techniques have enabled the characterization and determination of abundance levels of a wide range of biomolecules at molecular and system-wide...
The furanyl diterpenoid family of natural products has drawn the attention of both synthetic organic chemists and pharmacologists due to their complex structural architectures and diverse biological activity. Among them, wortmannin has been most extensively studied for biological activities. All these furanyl diterpenoids consist of a highly strained naptha[1,8-bc]furan core,...
Pharmaceuticals, molecular catalysts, and secondary metabolites often contain nitrogen. The problems faced synthesizing compounds which contain nitrogen was because of the Lewis base reactivity of nitrogen lone pairs, and the acidic protons of some nitrogenous functional groups. We developed two methods for the synthesis of nitrogeous compounds. Additionally, we successfully...
Widespread installation of renewable energy sources, such as wind and solar, has been delayed by the lack of suitable stationary energy storage solutions. Current large-scale technologies, such as pumped hydro and compressed air, are geographically restricted. This is where electrochemical energy storage - batteries or hybrid capacitors can play a...
Grid-scale energy storage systems are urgently needed to increase the flexibility and rigidity of the grid for modern society and take full advantage of the renewable green energy resources such as solar energy and wind energy. Na-ion batteries (NIBs) and K-ion batteries (KIBs) have been emerged as one of the...
Frontier research of non-aqueous actinide clusters is discussed. Since the inception of the uranyl peroxide clusters over the last decade, they have only been synthesized and characterized as solid crystals and in aqueous solution. This thesis provides thorough characterization of aqueous uranyl clusters and the first demonstration of uranyl cluster...
My work has focused on investigating synthetic organic reactions using applied computational methods. Non-covalent interactions are critical to catalysis, mechanism, and stereoselectivity, with the most prominent interaction for isothioureas being the S···O contact between the catalyst sulfur atom and the oxygen of the acyl group. A comprehensive joint experimental and...
Fungi have long been a prolific source of clinically approved drugs. The antibiotic penicillin, the cholesterol lowering statins, and the immunosuppressant cyclosporine have changed the treatment of human diseases in the last century. Recently, genome analysis of filamentous fungi has revealed that the biosynthetic potential for natural product expression is...
The synthesis of superheavy element evaporation residues is described by the product of the capture cross section, fusion probability, and survival probability. Capture cross sections are moderately well known. The fusion probability is the least known with many uncertainties. The formalism for the survival probability is known, but the parameters...
Two perovskite materials (Bi0.5(A)0.5)(Sc0.5Nb0.5)O3, where A = K+ and Na+ were synthesized phase pure for the first time. Their structures were determined by indexing synchrotron X-ray diffraction data and subsequent combined Rietveld refinement on neutron and synchrotron X-ray diffraction data revealing significant disorder on the A-sites of these materials. A...
Iron oxide materials including ferrihydrite and magnetite play essential roles in contaminant transport, pH control of surface and groundwater, and microbial activity. They have various applications ranging from data storage to cancer therapy. Recent studies showed that the NPs growth does not involve atom by atom nucleation but starts by...
Inorganic structures play an important role in materials due to their versatility and diversity. A complete understanding of the structure of a material is vital to enhance the creation of new materials that fill voids in research. The rational design of these compounds is driven by the exploitation of structure-property...
The general theme of this dissertation is the application of novel carbon based micro sensors with the scanning electrochemical microscopy (SECM). SECM allows positioning of the probe without touching the substrate while mapping the chemical parameters in 3D space above the substrate. The main focus of the dissertation is the...
Polyoxometalates are discrete anionic oxo clusters of the Group V and VI transition metals that can be conceptualized as molecular metal oxides. Because they are pairable with any alkali cation, a great deal of fundamental chemistry can be gleaned from their study, including solubility trends and insight into cation binding...
The post-emission total kinetic energy release (TKE) in the neutron induced fission of ²³²Th was measured (using white spectrum neutrons from LANSCE) for neutron energies from En = 3 to 91 MeV. In this energy range the average post-neutron total kinetic energy release decreases from 162.3 ± 0.3 at En...
State-of-the-art, high-resolution mass spectrometry techniques for acquisition of metabolomic and lipidomic data coupled with advanced computational methods provide new opportunities for interpreting large and complex datasets and comprehending the underlying biological processes of diseases. Both metabolomics and lipidomics strive to obtain comprehensive analyses of small molecules, i.e., metabolites and lipids,...
The solution chemistry and kinetic behavior of hafnium peroxy sulfate solutions ("HafSOx") is described in terms of peroxide content and solution speciation. Additionally, thin film behavior, including thermal behavior and solubility, is characterized, and a mechanism of patterning is presented, as well as parameters that should be considered when looking...
Femtosecond stimulated Raman spectroscopy (FSRS) is a powerful ultrafast technique which can track photoinduced excited state structural events on femtosecond (fs) to picosecond (ps) timescales. In addition to high temporal and spectral resolutions, FSRS provides a broad spectral window from ca. 100—2000 cm-1 for detection, enabling the direct mapping of...
Pactamycin, first reported in 1962, is a potent antitumor antibiotic produced by the soil bacterium Streptomyces pactum. Structurally, it contains a cyclopentitol core unit, a 3-aminoacetophenone (3AAP), a 6-methylsalicylic acid (6-MSA), and a N,N-dimethyl urea. The aminocyclopentitol ring is derived from glucose, possibly via N-acetyl glucosamine (GlcNAc), the 3-aminoacetophenone (3AAP)...
Femtosecond stimulated Raman spectroscopy (FSRS) is an ultrafast vibrational technique which allows rapid collection of Raman spectra with simultaneously high temporal and spectral resolution. With the recent development of FSRS methodology, three FSRS techniques (conventional, tunable, and anti-Stokes) have been implemented in our laboratory to dissect the excited state structural...
Novel donor-typed ternary graphite intercalation compounds (GICs) are synthesized and characterized containing (1) pyrrolidinium cations with DMSO co-intercalates; (2) alkali metal cations with crown ether co-intercalates; and (3) alkali metal cations with polyethylene glycol co-intercalates. Structural and compositional data are obtained for the stable products. A new ether-amine co-intercalate exchange...
The first part of this manuscript is about the total synthesis of the Arundo donax bis(indole) natural products. The A. donax alkaloids were prepared using the first example of an ynindole Diels–Alder reaction. Each were then separated, isolated, and determined to have stable enantiomeric conformations at room temperature (Chen, J.;...
Electrochemical capacitors and batteries are two major electrochemical energy storage technologies, which have been investigated extensively to meet the rapidly-growing demand for higher energy, higher power, lower cost and enhanced safety in the past few decades. With the charge storage mechanism of electrostatic charge adsorption desorption via electrical double layers,...
Polycyclic aromatic hydrocarbons (PAHs) are a group of environmental contaminants consisting of fused benzene rings. Parent-PAHs, methylated-PAHs (MPAHs), and PAHs with molecular weight of 302 a.m.u (MW302-PAHs) are considered as unsubstituted-PAHs. These unsubstituted-PAHs undergo transformation reactions resulting in the formation of PAH-transformation products (PAH-TPs), or substituted-PAHs, including nitrated-, oxygenated-, and...
This thesis is separated into three distinct projects. First, synthetic studies towards the furanosteroid viridin shown in part I. Second, synthetic studies towards the diperene obtusanal shown in part II. Third, the analysis, characterization, and synthesis of coronene derivatives towards their application in organic batteries shown in part III. Significant...
Pyroprocessing is an advanced technology for recycling used nuclear fuel. Pyrochemical processes encompass a wide range of chemical, physical, and electrochemical methods to partition fission products and other components from used nuclear fuel, which allows for the reuse of the actinides in nuclear fuel. This dissertation investigates two chemical systems...
In this dissertation, the spectroscopic properties and thermodynamic stability of a class of materials known as metal oxo and hydroxo clusters are studied. In aqueous solutions, many metals can aggregate into discrete clusters of metals bridged by oxo or hydroxo ligands. These clusters are of particular interest to us for...
Fluorescence has proven to be a robust and powerful method of analysis in numerous fields: forensics, pharmaceutics, geology, food science, and environmental sciences have all developed a large collection of fluorescence instruments and methods to overcome application-specific challenges. Biological applications saw the same development of a fluorescence toolkit with methods...
Oxo-hydroxo Group 5 metal clusters are an untapped resource to study and advance aqueous solution processing of metal oxide thin films. The tetramethylammonium (TMA) hexatantalate salt (TMA6[H2Ta6O19]) yields dense Ta2O5 films (~95% of the bulk ß-Ta2O5 density) with atomically smooth surfaces (<4 Å root mean square surface roughness). This same...
Aqueous hydroxo Hf nanoclusters enable studies to identify and codify steps in the deposition of Hf-based oxide thin films from solution precursors. HfOCl2 reacts with combinations of H2O2(aq), acids, and TMAH to produce polymetal species at high pH and low pH. X-ray scattering and spectroscopic methods reveal the nature of...