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Routes To Acylated Sydnones Utilizing Microwave Chemistry, Amber C. Rumple 2010 Wright State University

Routes To Acylated Sydnones Utilizing Microwave Chemistry, Amber C. Rumple

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In the present work, microwave chemistry was utilized to improve and optimize two methods for the acylation of sydnones. Whereas before, 4-acyl-3-arylsydnones could be synthesized by the use of Friedel-Crafts reactions utilizing either Montmorillonite K-10 or bismuth(III) triflate/lithium perchlorate as catalysts in moderate to good yields after long reaction times, with the introduction of microwave chemistry 4-acyl-3-arylsydnones can be synthesized in good to excellent yields in much shorter times. A previous method using Montmorillonite K-10 allowed for a variety of 4-acetyl-3-arylsydnones to be synthesized thermally in moderate to good yields after at least 24 hours. This method was ...


1-Alkyl-3-Methylimidazolium Bis(Trifluoromethylsulfonyl)Imide Based Ionic Liquids: A Study Of Their Physical And Electrochemical Properties, Charles William Dutton 2010 Wright State University

1-Alkyl-3-Methylimidazolium Bis(Trifluoromethylsulfonyl)Imide Based Ionic Liquids: A Study Of Their Physical And Electrochemical Properties, Charles William Dutton

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Ionic liquids are of interest because of their electrochemical and thermal properties and their possible use as electrolytes in batteries. In this work five ionic liquids were synthesized. They consisted of a 1-alkyl-3-methylimidazolium (RMI+) cation, where the alkyl group was ethyl, propyl, butyl, pentyl, or hexyl, and a bis(tri-fluoromethylsulfonyl)imide (NTf2-)anion. The decomposition temperatures, melting points, conductivities, viscosities, densities, absorption and desorption of water, diffusion coefficients, and electrochemical properties were studied. It was found that these ionic liquids were thermally stable up to ~310 °C, and that EMINTf2 had a melting point at -18.26 °C. Conductivities ...


Skeletal Pathology Of Tibiotarsi In Chick Embryos Exposed To Platinum Group Metals By Micro-Raman Spectroscopy, Jennifer L. Monahan 2010 Wright State University

Skeletal Pathology Of Tibiotarsi In Chick Embryos Exposed To Platinum Group Metals By Micro-Raman Spectroscopy, Jennifer L. Monahan

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Platinum group metals (PGMs) have been shown to accumulate in various tissues of organisms but their toxicity is not well-known. Raman spectroscopy is a powerful analytical technique that enables direct and non-destructive chemical characterization of bone tissues. PGMs were injected into chick embryos in the following concentrations: 0.1, 1.0, 5.0, or 10.0 ppm solutions of Pt(IV), Rh(III), Pd(II) or PGMs mixtures (0.1 ppm or 1.0 ppm of each metal). The micro-Raman maps recorded on the paraffin embedded tibiotarsus cross-sections showed significant changes in the chemical composition and structure of the bone ...


Electrochemical Oxidation Of Ethanol In Ionic Liquids And Its Possible Use In Fuel Cells, Ashley M. Mason 2010 Wright State University

Electrochemical Oxidation Of Ethanol In Ionic Liquids And Its Possible Use In Fuel Cells, Ashley M. Mason

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Electrochemical properties of EtOH in EMImBF4 ionic liquid were investigated and compared to the electrochemical properties of EtOH in 0.1M HClO4/H2O. As was shown earlier, oxidation of EtOH in HClO4/H2O involves formation of PtO on the electrode surface, which makes the electrode poisoned. We have found that the best procedure for removal of PtO from the Pt electrode is heating the electrode in concentrated H2SO4. Cyclic voltammograms obtained after cleaning several Pt electrodes conforms that this treatment gives clean Pt electrodes without any PtO. Electrochemical oxidation of EtOH in EMImBF4 ionic liquid show that is poisoning of ...


2,3-Bis(Bromomethyl)-1,4-Diphenylbenzene, Jonathan B. Briggs, Mikael D. Jazdzyk, Glen P. Miller 2010 University of New Hampshire

2,3-Bis(Bromomethyl)-1,4-Diphenylbenzene, Jonathan B. Briggs, Mikael D. Jazdzyk, Glen P. Miller

Chemistry Scholarship

In the title compound, C(20)H(16)Br(2), the terminal phenyl groups are twisted away from the central ring by approximately 55 and -125 degrees (average of four dihedral angles each), respectively. The crystal structure is stabilized by a combination of interMolecular and intraMolecular interactions including interMolecular pi-pi stacking interactions [C atoms of closest contact = 3.423 ( 5) angstrom].


The M-Superfamily Of Conotoxins: A Review, Reed B. Jacob, Owen M. McDougal 2010 Boise State University

The M-Superfamily Of Conotoxins: A Review, Reed B. Jacob, Owen M. Mcdougal

Chemistry Faculty Publications and Presentations

Throughout the world there exist both predator and prey. This distinction is apparent though sometimes misleading. Take for example marine snails of the genus Conus that are present across the oceans of the southern hemisphere [1]. These snails are slow moving animals that appear more prey than predator. However, they have evolved into effective predators through the development of venom consisting of biologically active peptides. The venom is loaded into a hollow harpoon that the snail injects into the intended prey: fish, worms, or other snails [2]. The categories of cone snails based on prey preference are piscivorous (fish eating ...


Construction, Figures Of Merit And Testing Of A Single-Cell Fluorescence Excitation Spectroscopy System, Laura S. Hill, Tammi L. Richardson, Louisa T.M. Profeta, Timothy J. Shaw, Christopher J. Hintz, Benjamin S. Twining, Evelyn Lawrenz, Micheal L. Myrick 2010 University of South Carolina - Columbia

Construction, Figures Of Merit And Testing Of A Single-Cell Fluorescence Excitation Spectroscopy System, Laura S. Hill, Tammi L. Richardson, Louisa T.M. Profeta, Timothy J. Shaw, Christopher J. Hintz, Benjamin S. Twining, Evelyn Lawrenz, Micheal L. Myrick

Faculty Publications

Characterization of phytoplankton community composition is critical to understanding the ecology and biogeochemistry of the oceans. One approach to taxonomic characterization takes advantage of differing pigmentation between algal taxa and thus differences in fluorescence excitation spectra. Analyses of bulk water samples, however, may be confounded by interference from chromophoric dissolved organic matter or suspended particulate matter. Here, we describe an instrument that uses a laser trap based on a Nikon TE2000-U microscope to position individual phytoplankton cells for confocal fluorescence excitation spectroscopy, thus avoiding interference from the surrounding medium. Quantitative measurements of optical power give data in the form of ...


Crossed-Beams And Theoretical Studies Of Hyperthermal Reactions Of O(3p) With Hcl, Jianming Zhang, Amy L. Brunsvold, Hari P. Upadhyaya, Timothy K. Minton, Jon P. Camden, Sophya V. Garashchuk, George C. Schatz 2010 University of South Carolina - Columbia

Crossed-Beams And Theoretical Studies Of Hyperthermal Reactions Of O(3p) With Hcl, Jianming Zhang, Amy L. Brunsvold, Hari P. Upadhyaya, Timothy K. Minton, Jon P. Camden, Sophya V. Garashchuk, George C. Schatz

Faculty Publications

The reaction of O(3 P) with HCl at hyperthermal collision energies (45-116 kcal mol-1 ) has been investigated with crossed-molecular beams experiments and direct dynamics quasi-classical trajectory calculations. The reaction may proceed by two primary pathways, (1) H-atom abstraction to produce OH and Cl and (2) H-atom elimination to produce H and ClO. The H-atom abstraction reaction follows a stripping mechanism, in which the reagent O atom approaches the HCl molecule at large impact parameters and the OH product is scattered in the forward direction, defined as the initial direction of the reagent O atoms. The H-atom elimination reaction is ...


Synthesis, Characterization And Development Of Catalysts For Co2 Capture, Anitha Suhas Wishrojwar 2010 University of Kentucky

Synthesis, Characterization And Development Of Catalysts For Co2 Capture, Anitha Suhas Wishrojwar

University of Kentucky Master's Theses

Fossil fuel and advanced industrialization techniques contribute to global warming through emissions of greenhouse gases such as CO2. In order to mitigate climate change, there is a desperate need to reduce CO2 emissions from different sources. CO2 capture and sequestration (CCS) play an important role in these reductions.

Naturally occurring enzymes, e.g., carbonic anhydrase (CA), can catalyze these reactions in living systems. Much effort has been focused on complexes of zinc with ligands such as teta, cyclen and tripodal ligands including BIMA and Trispyrazolylborates. These complexes have many interesting CO2 capture properties, but maintain toxic ...


Elucidation Of Fragmentation Pathways Of Nitrile-Terminated Ppi Dendrimer-Metal Complexes, Kristen Nicole Pack 2010 Marshall University

Elucidation Of Fragmentation Pathways Of Nitrile-Terminated Ppi Dendrimer-Metal Complexes, Kristen Nicole Pack

Theses, Dissertations and Capstones

The complexity of branching macromolecules around a core unit, such as poly(propylene)imine (PPI) dendrimers, has caught the attention of researchers for several years1,2,3,4,5. The structural framework of the core unit for these dendrimers is simply 1,4- diaminobutane. As the synthesis of higher-order generations of the macromolecule progresses, the molecules become very complex and tightly woven, but have predictable geometries and properties. The PPI dendrimers can be functionalized at the terminal ends of the branches in order to elicit different properties. The PPI dendrimer examined in this project has been terminated with a ...


The Synthesis, Structure, And Properties Of Group 2 Poly(Pyrazolyl)Borates And Their Use For The Atomic Layer Deposition Of Group 2 Borates, Mark J. Saly 2010 Wayne State University

The Synthesis, Structure, And Properties Of Group 2 Poly(Pyrazolyl)Borates And Their Use For The Atomic Layer Deposition Of Group 2 Borates, Mark J. Saly

Wayne State University Dissertations

A series of heavy alkaline earth complexes containing TpR2-based ligands has been synthesized, structurally characterized, and their properties were investigated. Salt metathesis routes involving MI2 (M = Ca, Sr, Ba) with either KTpEt2 or KTpnPr2 afforded MTpEt22 or MTpnPr22 in good to moderate yields. All of these complexes are volatile and exceptionally thermally stable, and have acceptable properties for use as group 2 atomic layer deposition (ALD) precursors. In addition, a series of group 2 complexes containing BpR2-based ligand systems were synthesized. Treatment of MI2 (M = Ca, Sr, Ba) with two equivalents of TlBptBu2, KBp, and KBpiPr2 in tetrahydrofuran at ambient ...


Synthetic Levers Enabling Control Of Phase, Size And Morphology In Transition Metal Phosphide Nanoparticles (Fe, Ni), Elayaraja Muthuswamy 2010 Wayne State University

Synthetic Levers Enabling Control Of Phase, Size And Morphology In Transition Metal Phosphide Nanoparticles (Fe, Ni), Elayaraja Muthuswamy

Wayne State University Dissertations

ABSTRACT

SYNTHETIC LEVERS ENABLING CONTROL OF PHASE, SIZE AND MORPHOLOGY IN TRANSITION METAL PHOSPHIDE NANOPARTICLES (FE, NI)

by

ELAYARAJA MUTHUSWAMY

May 2011

Advisor:Dr. Stephanie L. Brock

Major: Chemistry

Degree: Doctor of Philosophy

This dissertation study focuses on (1) development of a synthetic strategy to control phase in nanoscale iron phosphides; (2) extension of the developed phase control strategy to the nanoscale nickel phosphide system with simultaneous control on size and morphology and (3) illustration of the enhanced reactivity of nanoscale oxide systems.

A synthetic strategy to control phase in nanoscale iron phosphides was developed to prepare phase-pure samples of ...


Synthesis Of Functionalized Gpi Anchors And Related Glycoconjugates, Benjamin M. Swarts 2010 Wayne State University

Synthesis Of Functionalized Gpi Anchors And Related Glycoconjugates, Benjamin M. Swarts

Wayne State University Dissertations

This dissertation is divided into two chapters describing the background, significance, and synthesis of GPI anchors and GPI-anchored molecules. GPI anchors are a class of complex glycolipids with the primary purpose of attaching cell surface proteins/glycoproteins to the cell membrane. The first chapter is focused on the synthesis of functionalized GPI anchors, and begins with an introductory look at the discovery, structure, biosynthesis, and biological functions of GPIs. Then, after surveying progress and achievements in GPI synthesis, including discussion about current strategic shortcomings in the field that prevent the chemical synthesis of various GPI derivatives, our approach to accessing ...


Transition Metal-Mediated Higher-Order Cycloaddition Reactions: Application To The Total Synthesis Of Complex Natural Products, Bilal Abou Aleiwi 2010 Wayne State University

Transition Metal-Mediated Higher-Order Cycloaddition Reactions: Application To The Total Synthesis Of Complex Natural Products, Bilal Abou Aleiwi

Wayne State University Dissertations

ABSTRACT

TRANSITION METAL-MEDIATED HIGHER-ORDER CYCLOADDITION REACTIONS: APPLICATION TO THE TOTAL SYNTHESIS OF COMPLEX NATURAL PRODUCTS

by

BILAL ABOU ALEIWI

October 2010

Advisor: Dr. James H. Rigby

Major: Chemistry (Organic)

Degree: Doctor of Philosophy

Chromium (0)-mediated [6ð + 2ð] and [6ð + 2ð + 2ð] cycloaddition reactions between cyclic trienes and alkynes is reported. The development, investigation and the application of these reactions in the total synthesis of complex ring systems and natural products is described. Two natural products, namely, ∆ 9(12) -Capnellene and Echinopines A and B were targeted.

An investigation led to the successful development of a methodology to form the ...


I-Kinetic And Mechanistic Investigations Of Amino Acid Substrates Reactivities With Ferryl Species, Ahmed Ibrahim Youssef Abouelatta 2010 Wayne State University

I-Kinetic And Mechanistic Investigations Of Amino Acid Substrates Reactivities With Ferryl Species, Ahmed Ibrahim Youssef Abouelatta

Wayne State University Dissertations

ABSTRACT

I-KINETIC AND MECHANISTIC INVESTIGATIONS OF AMINO ACID SUBSTRATES REACTIVITIES WITH FERRYL SPECIES

II-SYNTHESIS AND CHARACTERIZATION OF DERIVATIVES OF THE BN-TPEN LIGAND AND THEIR METAL COMPLEXES

by

AHMED IBRAHIM YOUSSEF ABOUELATTA

MAY 2011

Advisor: Dr. Jeremy Jacob Kodanko

Major: Chemistry (Organic)

Degree: Doctor of philosophy

The reactivity of tryptophan, methionine, aspartic acid, glutamic acid, histidine and hydrochloride salt of lysine amino acid substrates with the N4Py ferryl species was studied by UV-vis spectroscopy and product characterization. Based on kinetic isotope effect studies and product analysis, an ET-PT mechanism was proposed for the reaction of tryptophan substrate with N4Py ferryl and ...


Synthesis And Characterization Of Metal Complexes Containing Tetrazolate, Poly(Tetrazolyl)Borate, And Aryl Pentazole Ligands As High Energy Density Materials, Dongmei Lu 2010 Wayne State University

Synthesis And Characterization Of Metal Complexes Containing Tetrazolate, Poly(Tetrazolyl)Borate, And Aryl Pentazole Ligands As High Energy Density Materials, Dongmei Lu

Wayne State University Dissertations

Heavier alkaline earth metal tetrazolates have been prepared as cryatals contain aqua ligands and as anhydrous powders, and were characterized by spectral and analytical methods. Potassium bis(tetrazolyl)borate complexes K(BH2(RCN4)2)(H2O)n (R = H, Me, NMe2, and NiPr2) and their 18-crown-6 adducts have been synthesized. In the solid state, complexes where R = H and Me have B-N bonds to the nitrogen atoms proximal to the carbon atom, whereas those with R = NMe2 and NiPr2 possess isomeric B-N bonds to the nitrogen atoms distal to the core carbon. With ...


Dechalcogenative Allylic Selenosulfide And Disulfide Rearrangements For Cysteine Modification And Glycoligation, Venkataraman Subramanian 2010 Wayne State University

Dechalcogenative Allylic Selenosulfide And Disulfide Rearrangements For Cysteine Modification And Glycoligation, Venkataraman Subramanian

Wayne State University Dissertations

This thesis describes investigations directed at the development of methods for the selenosulfide and disulfide rearrangements for the permanent functionalization of thiols, and in particular of cysteine and carbohydrate based thiols. Emphasis is placed on the newly invented silver mediated allylic desulfurative rearrangement for the primary modification of thiols and the synthesis of complex oligosaccharide mimics.

Chapter one introduces the concept of chemoselective ligations for the modification of macromolecules like carbohydrates and proteins. It overviews the native and non-native ligation techniques for their modification of such entities with a attention focusing on thiol based ligation techniques. The later part of ...


I. Microwave-Influenced Diversity-Oriented Synthesis Of Biologically Relevant Small & Natural-Product-Like Molecules Via Multicomponent Coupling Reactions Ii. Synthetic Studies Toward The Total Synthesis Of The Repeating Tetrasaccharide Unit Of Zwitterionic Polysaccharide Ps A1, Soumava Santra 2010 Wayne State University

I. Microwave-Influenced Diversity-Oriented Synthesis Of Biologically Relevant Small & Natural-Product-Like Molecules Via Multicomponent Coupling Reactions Ii. Synthetic Studies Toward The Total Synthesis Of The Repeating Tetrasaccharide Unit Of Zwitterionic Polysaccharide Ps A1, Soumava Santra

Wayne State University Dissertations

Microwave-influenced diversity-oriented synthesis of biologically relevant small and natural-product-like molecules via multicomponent coupling reactions (MCCRs) have been investigated. Cheap, readily available starting materials in conjunction of microwave irradiation and employment of environmentally benign solvent (e.g. water) provided a common platform that allowed to access a wide array of structurally and skeletally diverse molecules. The investigation allowed us to establish a new paradigm of diversity-activity relationships (DARs) by tuning reacting components of the MCCRs and proved that in contrary to the conventional use of microwave as a rate accelerating tool, it can be used to influence reactivity of molecules. The ...


Experimental Determination Of The Weiss Temperature Of Mn12-Ac And Mn12-Ac-Meoh, Christos Lampropoulos, Shiqi Li, Lin Bo, Bo Wen, M P. Sarachik, P Subedi, A D. Kent, Y Yeshurun, A J. Millis, S Mukherjee, G Christou 2010 University of North Florida

Experimental Determination Of The Weiss Temperature Of Mn12-Ac And Mn12-Ac-Meoh, Christos Lampropoulos, Shiqi Li, Lin Bo, Bo Wen, M P. Sarachik, P Subedi, A D. Kent, Y Yeshurun, A J. Millis, S Mukherjee, G Christou

Chemistry Faculty Publications

We report measurements of the susceptibility in the temperature range from 3.5 to 6.0 K of a series of Mn12-ac and Mn12-ac-MeOH samples in the shape of rectangular prisms of length lc and square cross section of side la. The susceptibility obeys a Curie-Weiss law, χ=C/(T−θ), where θ varies systematically with sample aspect ratio. Using published demagnetization factors, we obtain θ for an infinitely long sample corresponding to intrinsic ordering temperatures Tc≈0.85 K and ≈0.74 K for Mn12-ac and Mn12-ac-MeOH, respectively ...


Thermal And Electrochemical Characterization Of Cathode Materials For High Temperature Lithium-Ion Batteries In Ionic Liquids, Jodie R. Shoaf 2010 Wright State University

Thermal And Electrochemical Characterization Of Cathode Materials For High Temperature Lithium-Ion Batteries In Ionic Liquids, Jodie R. Shoaf

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Finding a cathode material to operate a high-temperature Li-ion battery in the presence of an ionic liquid has become an attractive area of research. Three cathode materials, LiCoO2, Li4Ti5O12, and LiFePO4, were received from Electrochemical Systems Inc. of Knoxville, TN. Three ionic liquids were synthesized using a 1-alkyl-3-methylimidazolium (XMI+) cation, where the alkyl group was either ethyl, pentyl or hexyl, and contained a bis(pentafluoroethylsulfonyl)imide (Beti-) anion. The thermal and electrochemical properties of each ionic liquid, of each cathode material, and each combination of cathode material in the presence of ionic liquid were studied. All of the ionic liquids ...


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