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The Synthesis And Characterization Of Novel 5,6-Disubstituted 1,10-Phenanthrolines, Liansheng Zeng

Masters Theses

Two new ligands, 5-amino-6-nitro-1,10-phenanthroline (5-NH₂-6-NO₂-phen), produced by amination of 5-NO₂-1,10-phenanthroline, and 5,6-diamino-1,10-phenanthroline (5,6-(NH₂) ₂-phen) ,produced by reduction of 5-NH₂-6-NO₂-phen, have been synthesized and characterized. The ligand 5-NH₂-6-NO₂-phen has been coordinated to a Ru(II) metal center to produce the Ru(II)-polypyridine complex [ (bpy) ₂Ru (5-NH₂-6-NO₂-phen)] (PF₆ ) ₂ (bpy= 2, 2' -bipyridine) . This complex has been characterized by IR, UV-Vis, ¹H-NMR, and cyclic voltammetry (CV) .

Novel Compounds (Including Transition-Metal Complexes) Based On 1,10-Phenanthroline-5,6-Dione, Hui Zhou

Masters Theses

This thesis describes the synthesis of the transition metal complex [(bpy) ₂Os^II (pptd)] (PF₆)₂^·2H₂O, an analog of [(bpy) ₂Ru^II (pptd)] (PF₆)₂^·2H₂O. Spectroscopic and electrochemical data on this complex are reported here. It was found that the electronic communication between the metal center and the pteridinedione portion of pptd did not appear to be enhanced in the Os(II) complex relative to its Ru(II) analog. The increased ability of Os(II) to undergo backbonding appeared to affect only the 1,10-phenanthroline portion of pptd.

A useful …

Electrochemical Studies Of Hemoglobin And Cross-Linked Hemoglobin, Ayoola O. Alabi

Master's Theses

No abstract provided.

New Optical Cell Design For Laser Flash Photolysis Studies In Supercritical Fluids, Steven R. Goates, Milton L. Lee, Qin Ji, Edward M. Eyring, Rudi Van Eldik, Kedika Bal Reddy

Faculty Publications

A high-pressure optical cell has been designed that achieves an effective separation between the chemical sample and the pressurizing medium and system. This design limits possible sample contamination and catalytic effects under supercritical fluid sample conditions. Laser flash photolysis experiments were carried out on molybdenum hexacarbonyl dissolved in supercritical CO2. The thermal ring closure reaction of the species Mo(CO)5L, where L is 2,2- bipyridine was found to proceed at rates comparable to those measured previously in liquid benzene or toluene. Much larger activation volumes were found for the reaction in supercritical CO2 than in liquid toluene.

Helical Stacking In Dna 3-Way Junctions Containing 2 Unpaired Pyrimidines - Proton Nmr-Studies, Neocles B. Leontis, Michael T. Hills, Martial Piotto, Igor V. Ouporov, Arun Malhotra, David G. Gorenstein

Chemistry Faculty Publications

The proton NMR spectra of DNA three-way junction complexes (TWJ) having unpaired pyrimidines, 5'-TT- and 5'-TC- on one strand at the junction site were assigned from 2D NOESY spectra acquired in H2O and D2O solvents and homonuclear 3D NOESY-TOCSY and 3D NOESY-NOESY in D2O solvent. TWJ are the simplest branched structures found in biologically active nucleic acids. Unpaired nucleotides are common features of such structures and have been shown to stabilize junction formation. The NMR data confirm that the component oligonucleotides assemble to form conformationally homogeneous TWJ complexes having three double-helical, B-form arms. Two of the helical arms stack upon …

Cs2ga2o(Bo3)2, Robert W. Smith

Chemistry Faculty Publications

The structure of dicaesium digallium diorthoborate oxide constitutes a new type of oxide borate. It consists of a three-dimensional gallium-oxide-orthoborate lattice with Cs atoms occupying large cavities in the lattice. This lattice is made from pairs of Ga atoms connected through a shared O atom along the [001] direction; these Ga dimers are interconnected through shared O vertices to trigonal BO3 groups along the [010], [110] and [i10] directions, completing the tetrahedral coordination environment of each Ga atom.

Studies On The Cyclization Of Cis-1,4-Dichloro-2-Butene With Sodium Dialkylmalonates, Hovis M. E. Imade

Master's Theses

No abstract provided.

Electrochemical, Chromatographic, And Spectrometric Studies Of An Osmium Containing Polymer, Lawrence John Rhodes

Master's Theses

No abstract provided.

Scf-Mo Conformational Analysis Of Polycroconaine, T. E. Ezell, Jerry A. Darsey

Journal of the Arkansas Academy of Science

Abinitio calculations at the STO-3G basis set level using GAUSSIAN 92 were conducted on the monomer unit of polycroconaine, a conducting polymer with conductive properties similar to several metals, in order to determine the most probable conformation of the monomer. We also compared the energy difference between the highest occupied and lowest unoccupied molecular orbitals. Successive calculations were performed at dihedral angle intervals of 30° around the central bond of the monomer. Minimum energy was observed at 0° bond rotation, consistent with a theory that the polymer owes many of its conductive properties to a planar configuration in combination with …

Spectroscopic Temperature Measurements For A Direct Current Arcjet Diamond Chemical Vapor Deposition Reactor, Scott W. Reeve, Wayne A. Weimer

Journal of the Arkansas Academy of Science

The diamond thin filmcommercial market isprojected to exceed one billion dollars by the year 2000. Potential applications of diamond thin films range from cutting tools to electronics tomedical devices. The explosion ofinterest in this fieldresults from the extreme properties diamond possesses: itis the hardest material known toman and yet, has a coefficient of friction similar to Teflon;its ability to conduct heat is five times that of copper; and diamond is completely inert. However, despite the tremendous economic incentive, there are still several technological barriers preventing diamond filmscale-up to commercial production. Included among these are a fundamental understanding of the gas …

Hammett Correlations Of Carbonyl 13c Chemical Shifts In A Series Of N-(4-Substituted Phenyl)-6-Chloro-5-Fluoronicotinamides, Frank L. Setliff, John W. Hawley, Alan D. Toland

Journal of the Arkansas Academy of Science

A series of nine N-(4-substituted phenyl)-6-chloro-5- fluoronicotinamides exhibited excellent correlations of their carbonyl 13C shifts (5CO,ppm as measured in DMSO) with the standard Hammett substituent constants (c?R) of the substituent inthe 4-position. The linear relationship was defined by the equation 8CO ¦ 1.22

Determination And Use Of Rohrschneider-Mcreynolds Constants For Chiral Stationary Phases Used In Capillary Gas Chromatography, Alain Berthod, Eve Yiwen Zhou, Kang Le, Daniel W. Armstrong

Chemistry Faculty Research & Creative Works

The overall polarity of 22 chiral stationary phases (CSPs) used in capillary open tubular gas chromatography columns was estimated using the first five Rohrschneider-McReynolds constants. Most of the columns (i.e., 18) were wall-coated, and four were of the wall-immobilized or of the so-called "bonded" type. A wall-coated capillary squalane column was specially prepared as a polarity reference column. All but two of the CSPs were based on derivatized cyclodextrins (CDs) of different sizes. The overall properties of the CSPs are discussed in terms of the five Rohrschneider-McReynolds constants and their average values. It was found that the derivatized cyclodextrin CSP …

Understanding Fertilisers For Table Grapes, B. H. Goldspink, I. Cameron, J. Campbell-Clause, N. Lantzke, C. Gordon

Viticulture research reports

A course run by the Department of Agriculture, Western Australia, August 1995.

The purpose of this publication is to clarify the role fertilisers play in commercial table grape production and to detail methods of selecting fertilisers. This selection process however is not easy as there are over 600 registered fertilisers in Western Australia.

In deciding which is the best fertiliser for a particular property many factors have to be considered. These include:

* Age of vine

* Rootstock

* Variety of table grape

* Soil type

* Soil chemistry

* Irrigation methods

* Previous fertiliser history Previous yield, vigour and …

The Synthesis Of N-Chlorosulfonyl Β-Lactams And Their Rearrangements, Lihua Zhang

Masters Theses

The synthesis of several N-chlorosulfonyl-β-lactams and their rearrangements have been carried out via CSI (chlorosulfonylisocyanate) reaction. The mechanism of β-lactam synthesis as well as its rearrangements were also studied. The characterization of β-lactams was performed with IR, ¹H and ¹³C NMR, and HRMS. β-lactams 2-chlorosulfonyl-1-methyl-2-azabicyclo[4.2.0]octan-3-one (71), 1-chlorosulfonyl-4-methyl-4- (phenylmethyl)azetidin-2-one (74) and 1-chlorosulfonyl-4,4- (diphenylmethyl)azetidin-2-one (75) were synthesized for the first time. β-lactam 4-chlorosulfonyl-3, 9, 9-trimethyl-4-azatricyclo [6.1.0.0^3,6] nonan-5-one (73) was obtained as crystalline solid instead of liquid.

Different effects, such as temperature, solvents and catalysts, on the rearrangement of the …

Equilibrium And Kinetic Studies Of Isomerization Of (Oc)5m[Η1-Pph2ch2ch(Pph2)2] And (Oc)5m[Η1-Pph2ch(Pph2)Ch2pph2] (M=Cr, Mo, W), Weiying Lin

Masters Theses

It has been found that (OC)₅M[η¹-PPh₂CH₂CH(PPh₂)₂] and (OC)₅M[η¹-PPh₂CH(PPh₂)CH₂PPh₂] (M=Cr, Mo, W) exist in equilibrium in solution. This linkage isomerization is the first experimental evidence for the exchange of terminal and coordinated phosphorus groups in pentacarbonyl complexes of group 6 metals.

(OC)₅M[η¹-PPh₂CH₂CH(PPh₂)₂] ⇌ (OC)₅M[η¹-PPh₂CH(PPh₂)CH₂PPh₂]

(M = Cr, Mo, W)

In this work, equilibrium …

Isomerization And Chelation Studies Of Dangling Phosphine Complexes Of Group 6, Zhongjiang Jia

Masters Theses

Vinyl addition reactions, catalyzed by 2,2'-azobis(isobutyronitrile) (AIBN), have been used to prepare six pentacarbonyl complexes of group 6, each of which contains a dangling Ph₂PCH₂CH₂P(p-tol)₂ ligand.

Each of the six complexes undergoes slow isomerizationand chelation at 55 °C in perdeuterated toluene:

The reactions were monitored by ³¹P{¹H} NMR spectroscopy. The isomerization reactions are reversible in solution, while the chelated products form irreversibly with the loss of carbon monoxide. The rate constants, K₁ and K_-1, have been determined for the three pairs of linkage isomers. Equilibrium …

The Synthesis And Characterization Of [Ruii (Bpy) 2 (Biphen) ] (Pf6)2 And [ (Bpy) 2ruii (Biphen) Ruii (Bpy) 2] (Pf6)4, Mei-Yueh Chang

Masters Theses

A new bidentate polypyridine bridging ligand (biphen), produced by the condensation of 1,10-phenanthroline-5,6-dione with 5,6-diamino-phenanthroline has been synthesized and characterized. In addition the monometallic complex [(bpy)₂Ru^II(biphen)](PF₆)₂ and the bimetallic complex [(bpy)₂Ru^II(biphen)Ru^II(bpy)₂](PF₆)₄ have been prepared. The complexes were characterized by elemental analysis, by ¹H-NMR spectroscopy and by cyclic voltsmmetry(CV).

The results of these analyses seem to indicate that biphen acts like two independent units when attached to a - Ru^II(bpy)₂ fragment. a bipyridine portion and a phenazine portion. Moreover, …

Effect Of Electrolyte Concentration, Temperature And Clay Type On The Diffusional Properties Of Anions In Clay-Modified Electrodes, Jennifer A. Stein

Dissertations

No abstract provided.

X-Ray Crystallographic Studies On Cross-Linked Hemoglobins, Elias J. Fernandez

Dissertations

No abstract provided.

Synthesis Of Model Tripeptides And Approaches To The Preparation Of A Transition State Analogue Of Phosphoramidon, Nadina Monberg

Master's Theses

No abstract provided.

Cis-6-Methoxycarbonyl-2,10-Dioxa-1-Phosphabicyclo[4.4.0]Decane 1-Oxide, Thomas M. Lane, Oscar P Rodriguez, Anthony Gerard Sommese, Sheldon E. Cremer, Dennis W. Bennett

Chemistry Faculty Research and Publications

The crystal structure of the title compound, C₉H1505P, is described. The molecule consists of two cis-fused six-membered rings, both in the chair conformation..

Synthesis Of Fluorinated Proline Analogs For The Potential Inhibition Of Proline Oxidase, Brent Hilbert

Honors Theses, 1963-2015

Proline oxidase is an enzyme that has been isolated from the inner membrane of rat liver mitochondria. It is the catalyst in the first step of the metabolic pathway for proline-glutamate interconversion. The enzyme is specific for L-proline which is oxidized to Æ-pyrroline- 5-carboxylic acid. 4,4- difluoro-L-proline has demonstrated irreversible inhibition of proline oxidase. Further kinetic studies of this inhibition need to be performed in order to elucidate a mechanism for the inhibition. Information regarding the site of the oxidation of proline may also be obtained from these studies. New synthetic routes to 4,4-difluoro-L-proline, and the "cis" and "trans" non- …

Tris(Diethyldithiocarbamato)(4-Methoxyphenyl)Tellurium(Iv), P-Meoc6H4Te(S2Cnet2)3, And The Triclinic Modification Of Tris(Diethyldithiocarbamato)Phenyltellurium(Iv), Phte(S2Cnet2)3, Steinar Husebye, Sergey V. Lindeman

Chemistry Faculty Research and Publications

No abstract provided.

Cis-(Diethyldithiocarbamato)Diiodo(Phenyl)Tellurium(Iv), Phte(S2Cnet2)I2, And Its Methoxy-Substituted Mixed Br/1 Analogue Cis-Bis(0.4-Bromo/0.6-Iodo)-(Diethyldithiocarbamato)(4-Methoxyphenyl) Tellurium(Iv), P-Meoc6H4Te(S2 Cnet2)(Br0.4I0.6)2, Steinar Husebye, Steffen Kudis, Sergey V. Lindeman, Peter Strauch

Chemistry Faculty Research and Publications

The Te^IV complexes PhTe(S₂CNEt2)I₂, (1), and p-MeOC₆H₄Te(S₂CNEt₂)Br_0.4/I_0.6) ₂, (2), have been synthesized by reacting PhTeI₃ with NaS₂CNEt₂, and p-MeOC₆H₄Te(S₂CNEt₂)₂I with Br₂, respectively. In (2), both I atoms are partially replaced by Br atoms in a 3:2 ratio. The structures display distorted octahedral Te coordination with two symmetrically coordinated S atoms [Te—S 2.550 (2)—2.569 (2) Å in three independent molecules of (1) and 2.523 …

Benz[4,5]Isoquino[1,2-B]Quinazoline-7,9-Dione And A Rearrangement Product Of Its Hydrolysis, 2-(1,8-Naphthalenedicarboximido)Benzamide, Sergey V. Lindeman, Igor I. Ponomarev, Alexandr L. Rusanov

Chemistry Faculty Research and Publications

No abstract provided.

Phosphorus Bearing Substrates In Ring Expansion Reactions, Bradley K. Norwood

Theses and Dissertations

A variety of substituted phosphonium salts, phosphorus ylides and phosphonates were studied to assess their utility in ring expansion reactions. The strategy involved formation of fused ring systems whose ring strain could be exploited to accomplish ring expansion to medium sized rings. β-Alkoxy vinylphosphonium salts were found to be unreactive with species such as the dimethylsulfoxonium methylide anion, Simmons-Smith type reagents. and carbenes in attempts to produce cyclopropyl phosphonium salts.

C-Alkylation of β-keto phosphorus ylides using haloalkanes bearing terminal groups that could be converted and reacted with the B-carbonyl, was also examined as a method for accessing strained rings bearing …

Ignition And Environmental Effects Of Wildfires As Related To Giant Impacts, Gregory S. Kufner

Honors Projects

Soot has been discovered by Wolbach et al. at the Cretaceous-Tertiary boundary in various geographic locations, supporting the theory that worldwide wildfires were ignited by the impact of a giant meteorite which caused the mass extinction 65 million years ago. This project examines a deep sea core sample from the North Central Pacific Ocean for evidence of soot. Soot discovery at this site, the only deep ocean site to be studied, supports the theory that soot distribution from the fires was worldwide. In another project, samples from the suevite breccia of the Kara Ust-Kara craters in Russia (unrelated to the …

Photochemistry Of The Nitrite Ion, Laura J. Wilson '95

Honors Projects

Nitrogen containing compounds contribute to many environmental problems such as acid rain, air pollution, groundwater contamination, and smog formation. For example, when the atmosphere is heavily polluted with nitrites and aromatic hydrocarbons, nitrogen compounds can undergo photochemical reactions to produce harmful compounds that can adversely affect the environment. This project studied the photochemistry of the nitrite ion in aqueous basic solution. Both ·OH and NO· radicals are produced during photolysis, but the two radicals recombine in the presence of pure water causing no net reaction. Aromatic compounds present in the solution being photolyzed can act as scavengers reacting with either …

Organochlorine Pesticide Residues In The Neotropical Migratory Passerine Birds, Birthe Borup

Honors Projects

In 1874 Othmar Ziedlert a German chemist was working on the synthesis and characterization of substituted aromatic hydrocarbons. In the process of his work he synthesized dichloro-diphenyl-trichloro-ethane commonly known as DDT. It was not until 1930 that its use as an insecticide was detected by Paul Muller who found that it was effective against potato beetles (Leptinotarsal declineata) and clothes moths, (Tineola besselliella ) (Dunlap 1981). Pure DDT is a white crystalline solid with a melting point of 109 C, and a vapor pressure of 0.025mPa at 20 C. Technical grade DDT is a white amorphous powder, consisting of a …

On-Road Remote Sensing Of Vehicle Emissions In Monterrey, N. L. Mexico, Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.