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Articles 1 - 30 of 292
Full-Text Articles in Inorganic Chemistry
Molybdenum Alkylidyne Complexes With Phenoxide Ligands For Alkyne Metathesis, Marvin L. Stewart Jr
Molybdenum Alkylidyne Complexes With Phenoxide Ligands For Alkyne Metathesis, Marvin L. Stewart Jr
LSU Doctoral Dissertations
Abstract
Alkyne metathesis is a powerful synthetic tool, which provides easy access to complex organic molecules in a single-step. It is a dynamic covalent reaction that scrambles alkynes, carbon-carbon triple bonds (C≡C). Molybdenum- or tungsten-alkylidyne (Mo≡C, W≡C) complexes are typically used as catalyst to cleave and reform alkyne bonds. Our goal has been to gain a deeper understanding of the intrinsic differences between functional ligands by the development of novel phenoxide ligands.
In chapter 2 we explore the detailed synthesis of novel phenoxide podand ligands in an effort to identify their mo-alkylidyne complexes. We were able to synthesize a variety …
Killing Cancer: Manipulating Hydrophobic Vanadium Complexes To Improve Anti-Cancer Activity, Levi Ausherman, Debbie C. Crans, Peter A. Lay, Maggi Braasch-Turi
Killing Cancer: Manipulating Hydrophobic Vanadium Complexes To Improve Anti-Cancer Activity, Levi Ausherman, Debbie C. Crans, Peter A. Lay, Maggi Braasch-Turi
SACAD: John Heinrichs Scholarly and Creative Activity Days
Hydrophobic vanadium complexes have recently shown improved anti-cancer activities compared to cisplatin. The hydrophobicity and anti-proliferative activity of [VO(Hshed)(dtb)] ([Hshed= N-(salicylideneaminato)-N’-(2-hydroxyethyl)-1,2-ethanediamine and dtb= 3,5-di(tert-butyl)catechol)]) have inspired the development of a library of hydrophobic vanadium complexes. Increasing the steric bulk of the catechol ligand has been shown to have a direct impact on hydrophobicity and anti-proliferative activities. Currently at Fort Hays State University, the Braasch-Turi group is synthesizing VO(HSHED)(dtb) to build up material to support the chemical analysis and biological assay performed by our collaborators at Colorado State University and the University of Sydney, Australia, respectively. In the future, we plan …
Mechanistic Investigation Of C—C Bond Activation Of Phosphaalkynes With Pt(0) Complexes, Roberto M. Escobar, Abdurrahman C. Ateşin, Christian Müller, William D. Jones, Tülay Ateşin
Mechanistic Investigation Of C—C Bond Activation Of Phosphaalkynes With Pt(0) Complexes, Roberto M. Escobar, Abdurrahman C. Ateşin, Christian Müller, William D. Jones, Tülay Ateşin
Research Symposium
Carbon–carbon (C–C) bond activation has gained increased attention as a direct method for the synthesis of pharmaceuticals. Due to the thermodynamic stability and kinetic inaccessibility of the C–C bonds, however, activation of C–C bonds by homogeneous transition-metal catalysts under mild homogeneous conditions is still a challenge. Most of the systems in which the activation occurs either have aromatization or relief of ring strain as the primary driving force. The activation of unstrained C–C bonds of phosphaalkynes does not have this advantage. This study employs Density Functional Theory (DFT) calculations to elucidate Pt(0)-mediated C–CP bond activation mechanisms in phosphaalkynes. Investigating the …
Exploring The Reactivity Of Metal-Ligand Cooperative Complexes With Dioxazolones, Terminal Alkynes, And 2-Ethynylbenzyl Alcohol, Megan A. Hoffer Miss
Exploring The Reactivity Of Metal-Ligand Cooperative Complexes With Dioxazolones, Terminal Alkynes, And 2-Ethynylbenzyl Alcohol, Megan A. Hoffer Miss
Electronic Thesis and Dissertation Repository
N-Acyl ketenimines were attempted to be synthesized catalytically by [Ru(Cp)(PPh2NPh2)(NCMe)]PF6 with phenylacetylene and 3-phenethynyl-1,2,4-dioxazol-5-one. Trapping agents were employed to identify the major product of the reaction, as many products were formed. [Ru(Cp)(PPh2NPh2)(NCMe)]PF6 reacts with 3-phenethynyl-1,2,4-dioxazol-5-one generating an isocyanate via the Curtius rearrangement, confirmed by a forced Curtius rearrangement with 3-phenethynyl-1,2,4-dioxazol-5-one and 1,2,4-triazole. Rates of vinylidene formation using [Ru(Cp)(PPh2NPh2)(NCMe)]PF6 and various terminal alkynes of different sterics and electronics were evaluated using a Hammett analysis for and simple rate comparisons. …
Optimization Of Transition-Metal Inclusive Carbon Aerogels For Electrochemical Energy Applications, Allen Dalton Davis
Optimization Of Transition-Metal Inclusive Carbon Aerogels For Electrochemical Energy Applications, Allen Dalton Davis
Electronic Theses & Dissertations
The ever-growing need for energy alongside rising concerns for climate change demands the development of renewable energy technologies. Hydrogen fuel cells are a promising technology that can serve to either supplement energy generation or act as a lone power source. Yet for these devices to be truly green, the hydrogen that serves as fuel must be procured from a renewable resource. Electrolytic water splitting is a process that allows for the dissociation of water into H2 and O2. For this process to be practical, the electrolyzer needs to demonstrate high efficiency and stability, as well as a …
Enhanced Mechanical Strength Of Soybean Oil-Based Non-Isocyanate Polyurethane Adhesive For Wood Application By Introducing Nanofillers, Vatsal Chaudhari
Enhanced Mechanical Strength Of Soybean Oil-Based Non-Isocyanate Polyurethane Adhesive For Wood Application By Introducing Nanofillers, Vatsal Chaudhari
Electronic Theses & Dissertations
Polyurethane (PU) is a versatile material that finds extensive use in various industries including bedding, construction, automotive, and packaging. Historically, this particular polymer relied significantly on petrochemical resources, a practice that was considered to have negative environmental impacts. The conventional method for preparing PU involves the use of isocyanate, which is a disadvantage due to its negative impact on the environment and human health. The resolution of this problem entails identifying an appropriate substitute for petroleum-derived products that minimize their impact on both the environment and human health. The researchers earlier utilized soybean oil, for the formulation of PUs in …
Exploring Soybean Oil-Based Polyol And Effect Of Non-Halogenated Flame Retardants In Rigid Polyurethane Foam, Sahithi Kondaveeti
Exploring Soybean Oil-Based Polyol And Effect Of Non-Halogenated Flame Retardants In Rigid Polyurethane Foam, Sahithi Kondaveeti
Electronic Theses & Dissertations
To address the increasing demand for sustainable biomaterials due to the depletion of fossil fuel resources and growing environmental concerns, a new type of biodegradable and environmentally friendly rigid polyurethane foam (RPUF) has been synthesized. These foams are derived from chemically modified soybean oil-based polyol obtained from soybean oil by epoxidation followed by a ring-opening reaction. Polyurethane foam is generally used in construction, furniture, and automobile industries but is highly flammable and releases toxic gases and smoke during combustion. In this study, a highly efficient synergistic effect halogen-free flame-retardant (FR) melamine salt, 2-carboxyethyl(phenyl)phosphinic acid melamine salt (CMA) was synthesized from …
Improved Stoichiometric Synthesis Of Ccc-Nhc Pincer Rh Complexes And Catalytic Activity Towards Dehydrogenative Silylation And Hydrosilylation Of Alkenes, Enock Amoateng
Theses and Dissertations
N-Heterocyclic carbenes (NHCs) have attracted growing interest not only as successful ancillary ligands in a wide variety of transition-metal-catalyzed reactions but have also shown to offer photophysical and electrochemical properties. The metalation/transmetalation strategy using [Zr(NMe2)4] as initial metalating reagent offers an efficient approach to the preparation of CCC-NHC pincer complexes of the late transition metals such as Rh and Ir. In the process of investigating an intermediate and the mechanism of the metalation/transmetalation to Rh sequence, a mixed valent bimetallic CCC-NHC pincer Rh complex with two chloro ligands bridged between a [(CCC-NHC)Rh(III)] and a [Rh(I)(COD)] fragment …
Rhodium-Catalyzed Asymmetric Synthesis Of P-P And P-C Bonds, Sarah T. Chachula
Rhodium-Catalyzed Asymmetric Synthesis Of P-P And P-C Bonds, Sarah T. Chachula
Dartmouth College Ph.D Dissertations
Chapter 1: Synthesis, Structure, Dynamics, and Enantioface-Selective η3-Benzyl Coordination in the Chiral Rhodium Complexes Rh(diphos*)(η3-CH2Ph) Abstract: The rhodium benzyl complexes Rh(diphos*)(η3-CH2Ph) (1-14, diphos* = chiral bis(phosphine)) were prepared either by treatment of Rh(COD)(η3-CH2Ph) (15, COD = 1,5-cyclooctadiene) with diphos*, or from the reaction of [Rh(diphos*)(Cl)]2 (16- 20) with PhCH2MgCl. For C2-symmetric diphos*, observation of one set of NMR signals for complexes 1-12 suggested that the two diastereomers in which different 3-benzyl enantiofaces were coordinated to rhodium interconverted rapidly on the NMR time scale via suprafacial shifts; observation of five inequivalent aryl 1H NMR signals showed that antarafacial shifts were slow …
N–((2–Acetylphenyl)Carbamothioyl)Benzamide: Synthesis, Crystal Structure Analysis, And Theoretical Studies, Akin Oztaslar, Hakan Arslan
N–((2–Acetylphenyl)Carbamothioyl)Benzamide: Synthesis, Crystal Structure Analysis, And Theoretical Studies, Akin Oztaslar, Hakan Arslan
Karbala International Journal of Modern Science
N–((2–Acetylphenyl)carbamothioyl)benzamide has been synthesized and characterized. The molecular conformation of the investigated compound is stabilized by C16–H16B⋅⋅⋅O2i (i: 1+x, y, z) intermolecular and C14–H14⋅⋅⋅S1, N2–H2⋅⋅⋅O2, and N2–H2⋅⋅⋅O1 intramolecular H–bonds. All DFT calculations have been implemented at the B3LYP level with the 6–311G(d,p) basis set. The optimized molecular structure parameters have been compared with the experimental one in the solid phase. The energy gap, global chemical reactivity descriptor parameters, MEP, Fukui functions, DoS, NLO, and NBO analysis were also computed and investigated. The intermolecular interactions and their energies are evaluated using Hirshfeld surface and energy framework analyses. To determine …
Synthesis Of A Phenyl Substituted Zinc Dipyrrin Complex For The Purpose Of Analyzing Aromatic Substitutions On The Characteristics Of Compounds Of This Class, Kole Owen
Undergraduate Honors Theses
The field of photochemistry is as innovative in development as it is broad in application. However, utilization of energy from the sun’s electromagnetic radiation remains secondary to the combustion of fossil fuels for the global energy consumption. This is neither a sustainable nor renewable system, and it has contributed to a major decline in the health of our global environment as the greenhouse gases emission has led to an incline in global temperatures and ocean acidity. To develop effective ways to utilize solar energy, experimental effort is being directed towards the understanding of photosensitizers, molecules which absorb solar radiation and …
Synthesis Of 2-Bromo-6-Alkylaminopyridines, 2,6-Dialkylaminopyridines, And Tren Based Ligands, Stephanie E. Carter
Synthesis Of 2-Bromo-6-Alkylaminopyridines, 2,6-Dialkylaminopyridines, And Tren Based Ligands, Stephanie E. Carter
Honors College Theses
Extended metal atom chains (EMAC) are multimetallic complexes that feature a linear metal chain with metal-metal bonds surrounded by stabilizing ligand molecules. When EMACs are formed with paramagnetic metal ions, unique magnetic properties can be derived from direct metal to metal communication. The challenge is that EMAC complexes are challenging to synthesize due to the inherent weakness of most M-M bonds and the specificity of the ligands required to stabilize EMACs. In prior work by the Guillet group, the silyl aminopyridine (SAP) ligands were observed to stabilize very unique triiron complexes, but they were inherently unstable. In other work, scaffolded …
Synthetic, Catalytic, And Mechanistic Studies Of Supermesityl Phosphiranes And Phosphines, Ryan M. Tipker
Synthetic, Catalytic, And Mechanistic Studies Of Supermesityl Phosphiranes And Phosphines, Ryan M. Tipker
Dartmouth College Ph.D Dissertations
Methylation of P-stereogenic phosphiranes Mes*PCH2CH(R) (Mes* = 2,4,6-(t-Bu)3C6H2, R = Me, Ph) with MeOTf gave P-stereogenic phosphiranium cations; [Mes*P(Me)CH2CH(Ph)][OTf] underwent syn-anti isomerization via P-epimerization. Mechanistic studies suggested ring opening gave a hyperconjugation-stabilized carbocation in which pyramidal inversion at P was promoted by s-interaction with the pendant cation. Attempted phosphirane protonation with HOTf resulted in ring opening and C-H activation of an o-t-Bu group to give phospholanium cations. Treatment of [Mes*P(Me)CH2CH(Ph)][OTf] with LiPPh2 gave bis(phosphino)ethanes. Copper- catalyzed P-alkylation of the secondary phosphine PHPh(Mes*) with benzyl bromides gave P-stereogenic tertiary phosphines with a supermesityl substituent.
Synthesis And Characterization Of Some Disubstituted Cyclopentadienyl Rhenium Complexes As Potential Candidates In Semiconductive Materials, Chloe Vernon
Senior Honors Theses
Since 2000, when the Nobel Prize in Chemistry as awarded for conductive polymer research few studies have been performed concerning the conductive capabilities of discrete organometallic compounds. For this project, organometallic compounds were formed specifically with a transition metal included in the structure. Through oxidation and reduction reactions, the variation in the electrical conductivity could allow for an analysis of whether this unique structure would allow for tunability. The goal of this research was to begin with aromatic substituted fulvenes and perform various multistep synthesis processes, utilizing thallium salt intermediates, to produce several disubstituted cyclopentadienyl rhenium complexes. In this project, …
Water-Soluble Palladium, Copper, And Nickel Catalysts And Their Formation In Ligand-Free Suzuki-Miyaura Cross-Coupling Reactions, Priya Karna
Theses and Dissertations--Chemistry
Transition-metal catalyzed Suzuki-Miyaura (SM) cross coupling is a powerful synthetic method for constructing carbon-carbon and carbon-heteroatom bonds in designing organic compounds, agrochemicals, pharmaceuticals, and precursors for materials. However, the nature of catalysis and identity of the transition metal catalysts used in these reactions remain under debate or unknown. This dissertation reports the studies of three metals: Pd, Cu, and Ni. Pd-nanocluster catalysts and their formation in ligand-free SM reactions with Pd(II) nitrate as a precatalyst was investigated. The catalysts are water-soluble neutral Pd tetramer and trimer in their singlet electronic states as identified by UV-Vis absorption spectroscopy and are formed …
Palladium (Ii)-Catalyzed Selective Reduction Of 4’-(Phenylethynl)Acetophenone In The Presence Of A Formic Acid-Triethylamine Mixture, Suzanne Chayya, Akram Hijazi, Anis Daou, Ali Alaaeddine, Mohamad Sakr, Ghassan Younes, Mohammad El-Dakdouki
Palladium (Ii)-Catalyzed Selective Reduction Of 4’-(Phenylethynl)Acetophenone In The Presence Of A Formic Acid-Triethylamine Mixture, Suzanne Chayya, Akram Hijazi, Anis Daou, Ali Alaaeddine, Mohamad Sakr, Ghassan Younes, Mohammad El-Dakdouki
BAU Journal - Science and Technology
An efficient and straightforward palladium acetylacetonate-catalyzed hydrogen transfer of 4'- (phenylethynyl)acetophenone was developed in this study. Formic Acid was found to be the best hydrogen source in this catalytic system in the presence of triethylamine. Excellent conversions and selectivity were obtained in reducing the starting internal aromatic alkyne to either (E)-1-(4- styrylphenyl)ethanone or an interesting cyclic product, 1-(phenanthrene-3-yl)ethenone, over the ketone functional group present. Over-reduction was rarely seen. The reaction conditions were optimized in terms of the choice of the palladium catalyst, temperature, solvent, and the H-donor/base combination. Using this catalytic system, a one-step synthetic pathway of the …
The Chemistry And Catalytic Activity Of Dehydrogenative Silylation And Hydroboration Of Complexes Bearing Semirigid Ligands With Group 14 Elements, Niroshani S. Abeynayake
The Chemistry And Catalytic Activity Of Dehydrogenative Silylation And Hydroboration Of Complexes Bearing Semirigid Ligands With Group 14 Elements, Niroshani S. Abeynayake
Theses and Dissertations
Incorporation of silicon in the ligand backbone would yield electron-rich metal complexes upon coordination to transition metal complexes. The coordination chemistry of semirigid benzyl phosphines bearing a single or multiple phosphorus atoms and varying number of Si−H moieties has gained interest in recent years. This dissertation focuses on synthesizing silyl and germyl transition metal complexes of groups 9 and 10. Chapter II presents the synthesis of a family of four coordinated 14-electron rhodium complexes. The newly synthesized complexes were characterized in solution by multinuclear NMR spectroscopy and in the solid-state by single-crystal X-ray diffraction. These d6 complexes possess sawhorse …
Designing And Synthesizing A Warhead-Fragment Inhibitory Ligand For Ivyp1 Through Fragment-Based Drug Discovery, Samuel Moore
Designing And Synthesizing A Warhead-Fragment Inhibitory Ligand For Ivyp1 Through Fragment-Based Drug Discovery, Samuel Moore
Symposium of Student Scholars
Fragment-based drug discovery (FBDD) is a powerful tool for developing anticancer and antimicrobial agents. Within this, magnetic resonance spectroscopy (NMR) provides a comprehensive qualitative and quantitative approach to screening and validating weak and robust binders with targeted proteins, making NMR among the most attractive strategies in FBDD. Inhibitor of vertebrate lysozyme (Ivyp1) of P. aeruginosa serves as an excellent target because of its active cellular location and implications in clinical prognosis for cystic fibrosis and immunocompromised patients. This study uses current NMR and biophysical techniques to develop a covalent, fragment-linked warhead inhibitor for Ivyp1 through synthetic methods, warhead linking, and …
Synthesis And Surface Modification Of Azide Decorated Silver Nanoclusters, Alexander H. Stöckli
Synthesis And Surface Modification Of Azide Decorated Silver Nanoclusters, Alexander H. Stöckli
Electronic Thesis and Dissertation Repository
In nanocluster research, easy modification of the cluster surface while maintaining the cluster core remains a key challenge. Herein we report the synthesis, structure, and properties of four targeted Ag20 nanoclusters (NCs) with surface azide moieties, two of which have 8 azide moieties, [CO3@Ag20(StBu)10(m-N3-C6H4COO)8(DMF)4] and [CO3@Ag20(StBu)10(p-N3-C6H4COO)8(DMF)4], and two of which have 6 azide moieties, [CO3@Ag20(S …
Synthesis And Characterization Of 2,6-Diisopropylphenoxy Tetrapyrazinoporphyrazines As Potential Molecular Qubits, Benjamin Marx
Synthesis And Characterization Of 2,6-Diisopropylphenoxy Tetrapyrazinoporphyrazines As Potential Molecular Qubits, Benjamin Marx
Masters Theses
This thesis reports the synthesis of metal-free and metal-containing phthalocyanine derivatives using methods typical for that class of functional dyes. A mixture of the target compounds prepared here, one paramagnetic and one diamagnetic tetrapyrazinoporphyrazine, will be tested for their potential use in spintronics – the application of spin-active species in molecular electronics. Phthalocyanines and their derivatives are well-known for their ease of preparation and tunability; they have been utilized as sensitizers for photodynamic therapy of cancer and solar cells, as well as in catalysis and chemical sensing. Tetrapyrazinoporphyrazine complexes are compared with the parent phthalocyanine as their chemistry is similar …
Catalytic Activity Of Tungsten-Dioxo And Tungsten-Diimido Complexes, Kayla Denike
Catalytic Activity Of Tungsten-Dioxo And Tungsten-Diimido Complexes, Kayla Denike
Graduate Theses and Dissertations
Due to the significant decline in the availability of petrochemical resources and the increasing demand for the useful olefin mixtures extracted from oil, a sustainable and efficient alternative to these materials has become vital. Fortunately, renewable biomass derived materials may serve as a sustainable solution to the limited resources problem. Molecules derived from the degradation of biomasses are highly oxygenated and highly functionalized. Developing processes to efficiently defunctionalize these oxygen-rich materials will lead to potential up-conversion to carbon chemicals. Homogeneous catalytic deoxygenation processes present an opportunity to access valuable carbon commodity chemicals from biomass derived polyols. This dissertation details the …
Alkylthiocarbamate Metal Complexes With Antiproliferation Activity., Kritika Bajaj
Alkylthiocarbamate Metal Complexes With Antiproliferation Activity., Kritika Bajaj
Electronic Theses and Dissertations
Bis(thiosemicarbazones) (BTSCs) and their metal complexes have been extensively studied for various applications including catalysis for hydrogen evolution reactions, treatment of neurodegenerative diseases, hypoxia imaging, and a wide range of pharmacological purposes including antitumor, antiviral, antibacterial, and antifungal agents. The paramount property that makes BTSC metal complexes interesting for their use in these applications is the reduction potential of the coordinated metal, which can be selectively tuned by varying the substituents present on the ligand framework. Although the BTSCs have shown a great deal of success as potential cancer therapeutic agents, they lack selectivity towards cancer cells. For this matter, …
Calcium Bistriflimide-Mediated Sulfur (Vi)–Fluoride Exchange (Sufex): Mechanistic Insights Toward Instigating Catalysis, Nicholas Ball, Brian Han, Samuel R. Khasnavis, Matthew Nwerem, Michael Bertagna, O Maduka Ogba
Calcium Bistriflimide-Mediated Sulfur (Vi)–Fluoride Exchange (Sufex): Mechanistic Insights Toward Instigating Catalysis, Nicholas Ball, Brian Han, Samuel R. Khasnavis, Matthew Nwerem, Michael Bertagna, O Maduka Ogba
Pomona Faculty Publications and Research
We report a mechanistic investigation of calcium bistriflimide-mediated sulfur(VI)–fluoride exchange (SuFEx) between sulfonyl fluorides and amines. We determine the likely pre-activation resting state─a calcium bistriflimide complex with ligated amines─thus allowing for corroborated calculation of the SuFEx activation barrier at ∼21 kcal/mol, compared to 21.5 ± 0.14 kcal/mol derived via kinetics experiments. Transition state analysis revealed: (1) a two-point calcium-substrate contact that activates the sulfur(VI) center and stabilizes the leaving fluoride and (2) a 1,4-diazabicyclo[2.2.2]octane additive that provides Brønsted-base activation of the nucleophilic amine. Stable Ca–F complexes upon sulfonamide formation are likely contributors to inhibited catalytic turnover, and a proof-of-principle redesign …
C-H On The Oxo Ferryl Wheel: Comparison Of Pyridine And Imidazole-Substituted Ligands For C-H Activation And Functionalization, Elizabeth Milem
C-H On The Oxo Ferryl Wheel: Comparison Of Pyridine And Imidazole-Substituted Ligands For C-H Activation And Functionalization, Elizabeth Milem
Electronic Theses and Dissertations
The selective and efficient transformation of hydrocarbon feedstocks is of high value for industry and research. While Shilov-type organometallic methods have facilitated this goal, systems designed after nature’s use of cheap and abundant iron-based enzymes are desired for wider-scale applications. This work establishes hydrocarbon oxidation efficiency of synthetic pyridine-based ligands (BPMEN, BPMPN) compared to commercially available TPA with in situ generated catalysts. Literature studies of traditionally synthesized BPMEN systems and initial in situ studies offered evidence for enhanced reactivity (TON) as compared to TPA. Expansion to a propyl backbone to produce BPMPN tested the increased chelate ring size’s impact on …
Analysis Of The Light Responsive Azobenzene Peptide Nucleic Acid Duplexes, Kat Nguyen
Analysis Of The Light Responsive Azobenzene Peptide Nucleic Acid Duplexes, Kat Nguyen
Honors College Theses
Peptide nucleic acids (PNAs) are oligonucleotide analogues in which the sugar-phosphate backbone has been replaced by a pseudopeptide skeleton. Since PNAs use the natural nucleobases (Adenine, Thymine, Cytosine, Uracil, and Guanine) found in either DNA and/or RNA, they are able to hybridize according to Watson-Crick base-pairing to form duplexes. PNA is a promising therapeutic agent because they can function as antigene or antisense chemical agents. To further enhance their utility, we aim to incorporate a photoswitchable moiety using azobenzene. Here, we report the results of the synthesis and purification of a photoswitchable 11 mer PNA along with initial characterization efforts.
Influence Of Tethered, Axially Coordinated Ligands On Rh(Ii,Ii)-Catalyzed Carbene Transfer Reactions, Cristian E. Zavala
Influence Of Tethered, Axially Coordinated Ligands On Rh(Ii,Ii)-Catalyzed Carbene Transfer Reactions, Cristian E. Zavala
Doctoral Dissertations
Dirhodium (II,II) paddlewheel complexes have become ubiquitous in diazo-mediated carbene transfer reactions. The Rh(II,II)-carbene intermediate is capable of a large variety of transformations such as cyclopropanation, C-H and X-H (O, N, S, Si, B) insertion reactions, cyclopropenations, and ylide transformations. Cyclopropanation reactions resulting in the formation of functionalized cyclopropane structures has always been a major focus in Rh(II,II)-carbene chemistry. Improvements on catalytic performance in cyclopropanations has largely focused on the modification of the bridging ligands and has resulted in Rh(II,II) catalysts that exhibit high reactivity and selectivity in cyclopropanation reactions. However, high enantio- and diastereoselectivity is not easily achieved with …
Light Harvesting And Electrically Conducting Metal-Organic Frameworks, Monica Gordillo Varela
Light Harvesting And Electrically Conducting Metal-Organic Frameworks, Monica Gordillo Varela
All Dissertations
Composed of metal clusters nodes and organic linkers, metal-organic frameworks (MOFs) have emerged as versatile platforms with unparalleled chemical and structural tunability, synthetic facility, permanent porosity, and size-selective guest encapsulation capability. These features make them potential candidates for a variety of applications such as gas storage,drug delivery, catalysis,and sensing. In recent years, the introduction of redox- and photoactive components have yielded stimuli-responsive electronic and photonic MOFs and expanded their utility in molecular electronics and energy storage devices/technologies.
Chapter one describes the light-harvesting ability of a porphyrin-based MOF. Herein, we have demonstrated spontaneous solvothermal growth of [100]-oriented uniform pillared-porphyrin framework-11 (PPF-11) …
Valorization Of Biopolymers And Biomass To Produce Materials For A More Circular Economy, Moira Lauer
Valorization Of Biopolymers And Biomass To Produce Materials For A More Circular Economy, Moira Lauer
All Dissertations
With a globally increasing population and largely unchecked consumption of raw materials, human society is on track for devastating consequences. Two industries responsible for utilizing massive amounts of raw materials and generating equally gargantuan quantities of waste are the packaging and infrastructure sectors. In 2017 in Europe, for example, packaging reached a record 173 kg of packaging waste per capita. One of the largest packaging consumers is the food industry, in which 40% of packaging is made of petroleum-derived single-use plastic, leading to a massive carbon imbalance. “The Built Environment,” on the other hand, is responsible for about 50% of …
Understanding Interfacial Reactions Initiating On Electrode Materials For Energy Storage Technologies, Jingnan Li
Understanding Interfacial Reactions Initiating On Electrode Materials For Energy Storage Technologies, Jingnan Li
Graduate Theses and Dissertations
Since the first generation of lithium-ion batteries featured lithium cobalt oxide cathode and carbon anode commercialized in the 1990s, the high-capacity materials with lower cost are in demand to further increase the battery energy density. Lithium metal and silicon anode are promising high-capacity anode materials to achieve next-generation lithium batteries. However, both the materials actively react in electrolytes and suffer from dramatic volume change. Therefore, a reliable passivation layer at the electrolyte/electrode interphase (i.e., solid electrolyte interphase, or “SEI”) is required to support the long-term cycling of both materials. Cetrimonium hydro fluoride (CTAHF2) has been proposed and synthesized as an …
Comparing And Contrasting Therapeutic Drugs Vs. Lifestyle Changes That Combattype-Ii Diabetes, Alexander Cline Helmuth
Comparing And Contrasting Therapeutic Drugs Vs. Lifestyle Changes That Combattype-Ii Diabetes, Alexander Cline Helmuth
Chemistry & Biochemistry Student Projects
In this thesis, I will be presenting various preventive approaches to combat type-II diabetes. The focus of this paper will be comparing and contrasting therapeutic drug targets such as Metformin and Sulfonylureas that are prescribed for type-II diabetic patients versus taking preventative steps such as making lifestyle changes including weight management, physical activity, and having a balanced diet that prevents onset of type-II diabetes or helps patients manage type-II diabetes. From this paper, one will gain insight on how there are multiple approaches to combat type-II diabetes that are not in the form of the pill.