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Synthesis And Electrodeposition Of Mixed Metal Trinuclear Clusters Of Molybdenum And Chromium In Ionic Liquid Onto A Platinum Electrode, Lynn Renee Frock
Synthesis And Electrodeposition Of Mixed Metal Trinuclear Clusters Of Molybdenum And Chromium In Ionic Liquid Onto A Platinum Electrode, Lynn Renee Frock
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Electrochemical properties of [Mo3O2(O2CCH3)6(H2O)(CF3SO2H)2 and [Cr2Mo(u2-CH3COO)6(u3-O)(H2O)3][CF3SO3] in 1-ethyl-3-methylimidazolium bis(pentafluoroethanesulfonyl)-imide ionic liquid was investigated. Cyclic voltammograms using a Platinum electrode indicated deposition had occurred for the [Mo3O2(O2CCH3)6(H2O)(CF3SO2H)2 metal cluster but had not for the polynuclear complex [Cr2Mo(u2-CH3COO)6(u3-O)(H2O)3][CF3SO3]. Constant potential electrolysis of -1.23 V using a platinum foil electrode was performed. Scanning electron microscopy in combination with energy dispersion spectroscopy confirmed that deposition had occurred.
The Synthesis Of Haplomyrtin Utilizing The Triisopropylsilyl Protecting Group, William S. Barrow
The Synthesis Of Haplomyrtin Utilizing The Triisopropylsilyl Protecting Group, William S. Barrow
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The synthesis of the arylnaphthalene lignan haplomyrtin using vanillin as a starting material is synthesized via: 1) a bromination of vanillin, 4-hydroxy-5-methoxybenzaldehyde, to produce 6-bromovanillin 2) a hydroxyl protection step of 6-bromovanillin with triisopropylsilylchloride to produce 2-bromo-4-triisopropylsilyoxy-5-methoxybenzaldehyde 3) an aldehyde protection step through a cyclic acetal formation using ethylene glycol to produce 2-(2-bromo-4-triisopropylsilyloxy-5-methoxyphenyl)-1,3-dioxolane 4) a lithium for halogen exchange of the doubly protected 6-bromovanillin leads to neucleophilic coupling with piperonal producing 1,3-benzodioxol-5-yl-[5-triisopropylsilyloxy-2-(1,3-dioxolane-2-yl)-4-methoxyphenyl]methanol and 5) an acid catalyzed intramolecular cycloaddition /Diels Alder adduct with dimethyl acetylenedicarboxylate producing dimethyl 1-(1,3-benzodioxol-5-yl)-4-hydroxy-6-methoxy-7-triisopropylsilyloxynaphthalene-2,3-dicarboxylate.
Hydroquinone-Based Poly(Arylene Ether)S With Pendent Benzothiazole Or Benzoxazole And 3-Sulfonated Phenyl Sulfonyl Groups For Use As Proton Exchange Membranes, Huong Hoang
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A series of hydroquinone-based poly(arylene ether) copolymers, with truly pendent sulfonated phenyl sulfonyl groups and either benzothiazole or benzoxazole groups was synthesized for use as proton exchange membranes (PEM). Two homopolymers series, benzothiazole and benzoxazole based, were prepared via meta activated nucleophilic aromatic substitution polycondensation reactions. Two copolymer series of N-heterocyclic and sulfonated phenyl sulfonyl groups were synthesized via a similar method. The ratio of 3,5-difluoro-3'-sulfonated diphenylsulfone to 2-[3,5-bis-(4-hydroxyphenoxy)]benzothiazole or 2-[3,5-bis-(4-hydroxyphenoxy)]benzoxaole was varied to afford ion-exchange capacities ranging from 0.60 to 1.39 meq and 0.62 to 1.42 meq, respectively. Polymers were characterized by gel permeation chromatography (GPC), 13C NMR …
The Enhancement Of Peroxide-Cured Fluoroelastomer Rubber To Metal Bonding, Richard Hunter Cooke Iii
The Enhancement Of Peroxide-Cured Fluoroelastomer Rubber To Metal Bonding, Richard Hunter Cooke Iii
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A "combi-cured&" fluoroelastomer (FKM) rubber formulation was designed to yield 100% cohesive rubber failure when cured to cold-rolled steel with derivatives of polymeric silane adhesives. Three different categories of adhesives were tested: Unsaturated Polymeric Silane with Phosphonium Salt (UPSP-D), Unsaturated Polymeric Silane (UPS-L), and Saturated Polymeric Silane (SPS-L). Adhesion Inserts molded using ASTM Method D429 Method C all consistently yielded 100% cohesive rubber failure and showed adhesion strength in the range of 700 to 800 psi after being pulled at 2" per minute until break. After obtaining consistent 100% rubber failure, a design of experiment (DOE) was implemented to determine …
The Solvent-Free Synthesis Of And N-Methyl-N-Alkylpiperidinium Salts And Their Anion Exchange Reactions With Dilithium Phthalocyanine, Michael Joseph Krol Jr.
The Solvent-Free Synthesis Of And N-Methyl-N-Alkylpiperidinium Salts And Their Anion Exchange Reactions With Dilithium Phthalocyanine, Michael Joseph Krol Jr.
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A nucleophilic substitution reaction of N-methylpiperidine with bromopropane, bromobutane, bromopentane, bromohexane and bromoheptane was carried out in a Q-Tube with excess alkyl halide and yielded N-methyl-N-propylpiperidinium bromide, N-methyl-N-butylpiperidinium bromide, N-methyl-N-pentylpiperidinium bromide, N-methyl-N-hexylpiperidinium bromide and N-methyl-N-heptylpiperidinium bromide in yields from 85 to 92 %. The salts, which were solids at room temperature, were soluble in dichloromethane and were characterized by 1H and 13C NMR, elemental analysis and DSC. Two of the piperidinium bromides, N-methyl-N-propylpiperidinium bromide, N-methyl-N-butylpiperidinium bromide were used in an anion exchange reaction with dilithium phthlocyanine to yield N-methyl-N-propylpiperidinium lithium phthalocyanine and N-methyl-N-butylpiperidinium lithium phthalocyanine, respectively in 78 to 85% …
The Synthesis And Characterization Of 1,3-Bisphenylsulfonylacetone, 2,5-Dicarboethoxy-3,4-Di(4-Methylphenyl)Cyclopentadienone Dimer, And Dp-Ppv Polymers And Oligomers, Mark Robert Duffy
The Synthesis And Characterization Of 1,3-Bisphenylsulfonylacetone, 2,5-Dicarboethoxy-3,4-Di(4-Methylphenyl)Cyclopentadienone Dimer, And Dp-Ppv Polymers And Oligomers, Mark Robert Duffy
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An SN2 reaction between 1,3-dichloroacetone and benzenesulfinic acid sodium salt was carried out to produce 1,3-bis(phenylsulfonyl)acetone. A crystal structure for 1,3-bis(phenylsulfonyl)acetone was obtained. The SN2 reaction was followed by a condensation reaction with benzil but this did not yield a condensation product. A photo-active compound, 2,5-dicarboethoxy-3,4-di(4-methylphenyl)cyclopentadienone, was synthesized and was shown to undergo a unique, solid-state dimerization. Several reactions involving the ester functions were carried out but these did not yield the expected products, instead, structural rearrangements seemed to predominate. An asymmetric cyclopentadienone, 2-carbomethoxy-5-methyl-3,4-diphenylcyclopentadienone, was synthesized and it was reacted with norbornadiene to produce methyl 4-methyl-2,3-diphenylbenzoate. The benzoate was reduced …
Dual-Stimuli Responsive Poly(Ethylenimine)S With A Tunable Lcst For Gene Delivery, Mary Abraham
Dual-Stimuli Responsive Poly(Ethylenimine)S With A Tunable Lcst For Gene Delivery, Mary Abraham
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Hyperbranched poly(ethylenimine)s (HPEI) were modified with hydrophobic isobutyryl amide groups (HPEI-IBAm0.60) to cause an LCST. These modified polymers were then further substituted with hydrophobic alkyl chains (HPEI-IBAm0.60-R0.40), a mixture of alkyl chains and hydroxyethyl groups (HPEI-IBAm0.60-EtOH0.20-R0.20), and a mixture of alkyl chains and low molecular weight PEG (HPEI-IBAm0.60-PEG0.20-R0.20) to determine the effect of different functional groups on solubility behavior. At pH 7.4, all but three LCSTs were below body temperature (37 °C), while at pH 5, all but three LCSTs were above …
Iodo Containing Sulfone And Sulfonamide Based Poly(Arylene Ether)S, Fadwa G. Constandinidis
Iodo Containing Sulfone And Sulfonamide Based Poly(Arylene Ether)S, Fadwa G. Constandinidis
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In an ongoing project involving the synthesis of functionalized poly(arylene ether)s that carry pendent phenyl sulfonyl groups, the introduction of an iodo group was desired. The effects of fluorine position on the electrophilic iodination of the 2,4-, 2,6-, and 2,5- and 3,5-isomers of difluorodiphenylsulfone, DFDPS were studied. The relative reactivity, toward EAS, was probed via 13C NMR spectroscopy and verified experimentally by iodination with N-iodosuccinimide. The product mixtures and corresponding structures indicated that intermediate stability did not always correlate to reactivity. Model studies were also conducted on DFDPS isomers that successfully carry in iodo groups in a pendent …
Effect Of Sample History On Dissolution Rates Of Gypsum {010} Surfaces, Dennis Stefan Renier Lennaerts
Effect Of Sample History On Dissolution Rates Of Gypsum {010} Surfaces, Dennis Stefan Renier Lennaerts
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Mineral dissolution plays a significant role in geochemical processes such as carbon sequestration and isotope geochemistry. While factors such as temperature, pressure, and solution chemistry have been widely studied, the effects of sample history and surface morphology on dissolution rates have been studied to a lesser extent. This research focuses on the dissolution of cleaved, polished, and reacted samples of the atomically flat natural {010} cleavage plane of gypsum (CaSO4·2H2O) to further investigate upon the effect of sample history. Gypsum was chosen as the mineral of interest because of its planar crystal surface and relatively fast dissolution rate. Chemical dissolution …
Effect Of Sample Miscut On Dissolution Kinetics Of Calcite (104) Cleavage Surfaces, Tahiru Sulley Addo
Effect Of Sample Miscut On Dissolution Kinetics Of Calcite (104) Cleavage Surfaces, Tahiru Sulley Addo
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Calcite is one of the most abundant naturally occurring carbonate minerals in the earth crust, and it is believe to play a crucial role in the long-term effectiveness of geochemical process works such as geological carbon sequestration. Due to the ease in which clean, flat calcite surfaces may be prepared, a lot of dissolution studies have been carried out on its (104) cleavage plane. However in geologic media, natural calcite grains consist of alternate surface terminations that do not display similar crystallographic properties as the (104) cleavage plane. This study focuses on the effect of miscut and step orientation on …
Libraries From Libraries Approach To The Synthesis Of Arylidene Oxindoles, Kyle James Knisley
Libraries From Libraries Approach To The Synthesis Of Arylidene Oxindoles, Kyle James Knisley
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A libraries from libraries combinatorial chemistry approach was employed to synthesize fluorinated derivatives of both oxindoles and isatins as potential pharmaceuticals or targeting agents for imaging purposes related to cancer or Alzheimer's disease. Synthesis for these fluorinated derivatives are described by routes involving, either: a) N-alkylation of 5-substituted isatins followed by Wolff-Kishner reduction to the corresponding oxindoles and final Knoevenagel condensation with aryl aldehydes, or; b) Wolff-Kishner reduction of the isatins followed by condensation and finishing with the N-alkylation of the aldol products. In specific cases, a click reaction followed the N-alkylation of the aldol products to form the isatin …
The Synthesis Of Benzyloxy Substituted Dp-Ppvs, Ryan Oostendorp
The Synthesis Of Benzyloxy Substituted Dp-Ppvs, Ryan Oostendorp
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The alkyne 1-(benzyloxy)-4-(propargyloxy)benzene was reacted with 2,5-di(carboethoxy)3,4-diphenylcyclopentadienone to yield diethyl 5-((4-(benzyloxy)phenoxy)methyl)-2,3-diphenylterephthalate. The terephthalate was reduced with lithium aluminum hydride to produce 5-((4-(benzyloxy)phenoxy)methyl)-1,4-di(hydroxymethyl)-2,3-diphenylbenzene. The diol was reacted with thionyl chloride to yield the monomer 5-((4-(benzyloxy)phenoxy)methyl)-1,4-di(chloromethyl)-2,3-diphenylbenzene that has a pendent protected phenol function. The new compounds were characterized by melting point, IR, 1H NMR, 13C NMR spectroscopy and elemental analysis. Polymerization of the dichloro monomer via a Gilch polymerization yielded poly[(2,3-diphenyl-(5-((4-(benzyloxy)phenoxy)methyl)-1,4-phenylene) vinylene]. The polymer was characterized by IR, 1H NMR spectroscopy, TGA and DSC. The polymer was insoluble in most solvents but partially soluble in chlorinated solvents. The solid polymer fluoresced a …