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Full-Text Articles in Chemistry
Copper-Catalyzed Dehydrogenative Decarboxylation Reactions Of Carboxylic Acids To Alkenes, Michael P. Stanton
Copper-Catalyzed Dehydrogenative Decarboxylation Reactions Of Carboxylic Acids To Alkenes, Michael P. Stanton
Graduate Theses, Dissertations, and Problem Reports
Linear alpha olefins (LAOs) are important building blocks in the production of linear low-density polyethylene, a plastic used in products such as shrink wraps, plastic bags, tubing, plasticizers, among others. Commercial methods for generating LAOs utilize ethylene oligomerization, but this method is reliant on fossil fuels and leads to unselective product formation. Synthesis of LAOs from renewable resources, namely carboxylic acids, by decarbonylative dehydration strategies has been well studied, however, this method has inherent drawbacks rooted in the formation of internal olefin side-products through isomerization pathways. With the goal of avoiding internal isomerization, this thesis explores a dehydrogenative decarboxylation strategy …
Interactions Of Bioactive Trace Metals In Shipboard Southern Ocean Incubation Experiments, Shannon M. Burns, Randelle M. Bundy, William Abbott, Zuzanna Abdala, Alexa R. Sterling, P. Dreux Chappell, Bethany D. Jenkins, Kristen N. Buck
Interactions Of Bioactive Trace Metals In Shipboard Southern Ocean Incubation Experiments, Shannon M. Burns, Randelle M. Bundy, William Abbott, Zuzanna Abdala, Alexa R. Sterling, P. Dreux Chappell, Bethany D. Jenkins, Kristen N. Buck
OES Faculty Publications
In the Southern Ocean, it is well‐known that iron (Fe) limits phytoplankton growth. Yet, other trace metals can also affect phytoplankton physiology. This study investigated feedbacks between phytoplankton growth and dissolved Fe, manganese (Mn), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), and cadmium (Cd) concentrations in Southern Ocean shipboard incubations. Three experiments were conducted in September–October 2016 near the West Antarctic Peninsula: Incubations 1 and 3 offshore in the Antarctic Circumpolar Current, and Incubation 2 inshore in Bransfield Strait. Additions of Fe and/or vitamin B12 to inshore and offshore waters were employed and allowed assessment of metal (M) …
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, …
Synthetic Methods For Improved Scope And Efficiency Of Copper-Catalyzed Regioselective Alkene Boracarboxylation, Steven William Knowlden
Synthetic Methods For Improved Scope And Efficiency Of Copper-Catalyzed Regioselective Alkene Boracarboxylation, Steven William Knowlden
Graduate Theses, Dissertations, and Problem Reports
The synthesis of carboxylic acids is important to the chemistry community, owing to the broad applicability of these compounds as fine chemicals and pharmaceuticals. Method development over the last decade has focused on the preparation of carboxylic acids through transition metal catalysis utilizing CO2 as a C1 synthon. Copper-catalyzed heteroelement(bora and sila)-carboxylation protocols provide functional group rich carboxylic acid products, yet remain underdeveloped and thus underutilized. Consequently, catalytic reductive difunctionalization methodologies in which CO2 and B(pin) (pin = pinacolate: 2,3-dimethyl-2,3-butanediolate) are installed across the double bond of a vinyl arene were recently developed. These boracarboxylation protocols provided novel, …
Synthesis And Evaluations Of “1,4-Triazolyl Combretacoumarins” And Desmethoxy Analogs, Tashrique A. Khandaker, Jessica D. Hess, Renato Aguilera, Graciela Andrei, Robert Snoeck, Dominique Schols, Padmanava Pradhan, Mahesh K. Lakshman
Synthesis And Evaluations Of “1,4-Triazolyl Combretacoumarins” And Desmethoxy Analogs, Tashrique A. Khandaker, Jessica D. Hess, Renato Aguilera, Graciela Andrei, Robert Snoeck, Dominique Schols, Padmanava Pradhan, Mahesh K. Lakshman
Publications and Research
1,4-Triazolyl combretacoumarins have been prepared by linking the trimethoxyarene unit of combretastatin A4 with coumarins, via a 1,2,3-triazole. For this, 4-azidocoumarins were accessed by a sequential two-step, one-pot reaction of 4-hydroxycoumarins with (benzotriazol-1-yloxy)tris(dimethylamino)phosphonium hexafluorophosphate (BOP), followed by reaction with NaN3. In the reaction with BOP, a coumarin-derived phosphonium ion intermediate seems to form, leading to an O4-(benzotriazolyl)coumarin derivative. For the CuAAC reaction of azidocoumarins with 5-ethynyl-1,2,3-trimethoxybenzene, catalytic [(MeCN)4Cu]PF6 in CH2Cl2/MeOH with 2,6-lutidine, at 50 oC, was suitable. The 4-azidocoumarins were less reactive as compared to PhN3 and …
Development Of Copper-Catalyzed Suzuki-Miyaura Coupling Using Alkylboron Reagents And Nickel-Catalyzed Alkene Dicarbofunctionalization Reactions, Prakash Basnet
Development Of Copper-Catalyzed Suzuki-Miyaura Coupling Using Alkylboron Reagents And Nickel-Catalyzed Alkene Dicarbofunctionalization Reactions, Prakash Basnet
Chemistry and Chemical Biology ETDs
This thesis is divided into two parts. The first part deals with the development of copper-catalyzed Suzuki-Miyaura coupling of alkylboron reagents for the first time. In the second part, we will discuss the development of novel nickel-catalyzed alkene dicarbofunctionalization reactions.
Part I. Cross-coupling reactions are versatile tools to form new carbon-carbon bonds and are widely used in the synthesis of various drug molecules, natural products and materials. However, these reactions are typically catalyzed by palladium, an expensive and rare metal which makes the reaction unsustainable in long-terms. Additionally, palladium-catalyzed cross-coupling reactions with alkylorganometallic reagents suffer from side reactions due to …
Copper Mediated, Transmetallation Coupling Reactions Using High Intensity Ultrasound, Bryan J. Musolino
Copper Mediated, Transmetallation Coupling Reactions Using High Intensity Ultrasound, Bryan J. Musolino
Doctoral Dissertations
This dissertation summarizes research efforts focused on the use of boron and copper acetate to form new carbon-carbon and carbon-heteroatom bonds. Two new methods were developed using high intensity ultrasound as the reaction energy source. The first focused on the homocoupling of various aryl compounds using a commercially available polymer support. The use of this polymer support allows the reaction to proceed in an aqueous solvent system with only minimal preparation. The product yields were better than values reported in the literature using traditional reaction conditions and reaction times were decreased from 24-72 hours to 6 hours. The second method …
Synthesis Of Platinum And Platinum-Copper Branched Nanoparticles For Electrooxidation Of Methanol, Eric Courtland Taylor
Synthesis Of Platinum And Platinum-Copper Branched Nanoparticles For Electrooxidation Of Methanol, Eric Courtland Taylor
Graduate Theses and Dissertations
Platinum and Pt alloys are among the most important heterogeneous catalysts for many organic reactions and electrochemical reactions associated with the fuel cell technologies. How to reduce Pt usage while maintaining the performance of the catalysts becomes a subject for intensive research in materials chemistry. For heterogeneous catalysis, the catalytic reactivity and selectivity are strongly correlated with different crystallographic facets exposed on the surface. The facets with high-index planes whose Miller indices with at one is larger than unity are generally more active than those with low-index planes (e.g., {100}, {111}, and {110}). Tuning the morphology of the nanoparticles to …
Lipid Peroxides And Glutathione Status In Human Progenitor Mononuclear (U937) Cells Following Exposure To Low Doses Of Nickel And Copper, William Y. Boadi, Shalandus Harris, Justin B. Anderson, Samuel E. Adunyah
Lipid Peroxides And Glutathione Status In Human Progenitor Mononuclear (U937) Cells Following Exposure To Low Doses Of Nickel And Copper, William Y. Boadi, Shalandus Harris, Justin B. Anderson, Samuel E. Adunyah
Chemistry Faculty Research
Effects of Cu2+, Ni2+ or Cu2+ + Ni2+ on lipid peroxide and glutathione (GSH) levels in U937 cells were investigated. Cells were treated with 0, 5, 10, and 20 µM of Cu2+ and/or Ni2+ and H2O2 (0.01 mM) and incubated for 24 hours at 37°C. Lipid peroxides were measured by the thiobarbituric acid assay (TBA). GSH intracellular levels were assayed by the GSH assay kit from EMD/Calbiochem (San Diego, California, USA). Cu2+ or Ni2+ significantly (P < 0.01) increased lipid peroxides in a dose-dependent manner, compared to controls. The effect was more pronounced for Cu2+, compared to the Ni2+-treated samples. Cu2+ + Ni2+ increased lipid peroxides in a significant (P < 0.001), dose-dependent manner, compared to Cu2+ or Ni2+ alone (i.e., ratio of 2.5:1-fold for combined versus single treatments, respectively). Cu2+ or Ni2+ significantly decreased GSH levels in U937 cells, with the effect being pronounced for Cu2+. Cu2+ + Ni2+ metal ions significantly (P < 0.001) depleted cells of GSH in a dose-dependent manner. Ethylene diamine tetraacetic acid (EDTA) at 50 or 100 µM moderately reduced the Cu2+- or Ni2+-induced effects on GSH levels. Interestingly, GSH levels generally decreased to half (except for the combined metal dose of 20 µM at 100 µM EDTA) of its level at the highest metal concentration tested for both the single or combined treatments. In conclusion, multiple exposures of cells to metal ions may be lethal to cells, compared to their single treatments.
Oxidation Of Benzoins To Benzils Using Bismuth(Iii) Nitrate-Copper(Ii) Acetate, Ram Mohan, Steven Tymonko, Bryce Nattier
Oxidation Of Benzoins To Benzils Using Bismuth(Iii) Nitrate-Copper(Ii) Acetate, Ram Mohan, Steven Tymonko, Bryce Nattier
Scholarship
Benzoins are oxidized to benzils in excellent yields by 0.4 equivalents of Bi(NO3)3.5H20 and 4 mol% of Cu(OAc)23)3.5H20 is a stable, inexpensive, commercially available solid. The relatively low cost and low toxicity of bismuth(Ill) nitrate makes this procedure a particularly attractive method for oxidation of benzoins.
Oxidation Of Benzoins To Benzils Using Bismuth(Iii) Nitrate-Copper(Ii) Acetate, Ram S. Mohan, Steven A. Tymonko, Bryce A. Nattier
Oxidation Of Benzoins To Benzils Using Bismuth(Iii) Nitrate-Copper(Ii) Acetate, Ram S. Mohan, Steven A. Tymonko, Bryce A. Nattier
Ram S. Mohan
Control Of Copper, Zinc And Manganese Deficiencies In Fruit Trees, N J. Halse
Control Of Copper, Zinc And Manganese Deficiencies In Fruit Trees, N J. Halse
Journal of the Department of Agriculture, Western Australia, Series 4
THE three elements copper, zinc and manganese are plant nutrients of the type often referred to as minor or trace elements.
Although essential elements for plant growth, they are required in comparatively small quantities.