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Research was conducted to extend the study of the rearrangement to indazoles of 1,3-diaryl-substituted fused (1,2,3)triazolo(1,5-alpha)benzimidazolium and benzthiazolium salts which were heated at 80 degrees C. The study was extended for novel related ring systems. Results indicate that the ring opening of fused (1,2,3)triazolium salts is a general phenomenon and is closely related to the well-known retro-electrocyclizations of neutral fused (1,2,3)triazoles and tetrazoles.

A study was conducted to investigate a density functional theory (DFT) approach to the polyelectrolyte system where the hard sphere contribution to the excess free energy is measured through a nonperturbative weighted density approximation and the electrical contribution is computed by perturbation with respect of the uniform fluid. The DFT was found to agree well with Monte Carlo simulations for the density distribution of monovalent, divalent and mixed salts around charged cylinders. Results also showed that the DFT is more accurate than the Poisson-Boltzmann and HNC theories for divalent and mixed salts.

A comparative study was conducted to investigate the reactivity of primary and quaternary allylic and homoallylic alkenylammonium salts with dimethyldioxirane and m-chloroperbenzoic acid. The study determined the stereochemical outcome of the epoxidation of the cyclic quaternary allylic salt (2-cyclohexenyl)trimethylammonium p-chlorobenzenesulfonate with dimethyldioxirane and m-chloroperbenzoic acid. It also determined the epoxidation rate constants for the reaction of select allylic and homoallylic primary and quaternary ammonium salts.

The flash photolysis of Roussin's black salt (RBS) anion, Fe4S3(NO)7(super -) has been studied through time-resolved optical spectroscopy. Results indicate that two separate intermediates are formed after flash photolysis has occurred. The parent complex is regenerated when both intermediates react with nitric oxide. The decomposition of RBS is the result of the oxidative trapping of both intermediates by O2 followed by further redox processes.

Research was conducted to examine the synthesis of a dehydro precursor, which when treated with tritium would yield (super 3)H(sub 2)-lobeline in one step. The process began with chiral pyridium salt which was reduced to oxazolidine, a dihydropyridine equivalent, followed by the removal of the phenylethanol auxiliary with concomitant introduction of the methyl group at nitrogen. Results provides strong evidence that the salts of (-)-lobeline exists in solution as a single stereoisomer and validated the synthesis of this natural product.

The lithium, barium, ammonium and guanidinium salts of nitrosocyanomethanide ((ONC(CN)2)-) and the lithium, sodium, barium, ammonium, guanidinium and hydrazinium salts of nitrodicyanomethanide ((O2NC(CN)2)-) were synthesized and characterized. Structural data showed that the two anions have comparable structural features irrespective of the nature of the cation. Differential scanning calorimetry showed that the two series of compounds undergo exothermic decomposition.

A study on lithium salt systems investigated two factors which contribute to the establishment of a high ambient temperature conductivity in an ionic liquid. These factors are, namely, a high fluidity and a high conductivity/viscosity decoupling index. One aim of the study was to discover factors that determine the decoupling index on one hand and the glass transition temperature and fragility on the other hand for liquid salt mixtures which do not crystallize at ambient temperature.

A study on room temperature molten salts presents the first report of low molecular weight ammonium cation salts being molten at room temperature. The new family of salts is based on the pyrrolidinium cation IV where the two alkyl substituents range from methyl up to butyl. These salts are shown to have melting points below room temperature in some instances and exhibit interesting conductive behavior in their crystalline state in other cases.

A study on lithium halides in water was conducted to carry out a simple comparison of the extremes of the liquid state for two common lithium salt systems where concentrated solutions approaching the dihydrate could be investigated in both molten and supercooled states. The experimental results suggest the types of systems where higher boiling points might be obtained without undue increase on the glass transition temperature and, therefore, the viscosity.

A study on molten nitrate salts was conducted to obtain insights into the dynamics of their glassy state by investigating the ion dynamics in the fragile glass-former 2Ca(NO3)2-3RbNO3 using 87Rb nuclear magnetic resonance techniques. The experiment covered a broad temperature range, namely 8 K less than T less than 500 K. The temperature dependent spin-lattice relaxation rate exhibits two maxima. The maximum observed near 390 K reveals that the ionic motion causing both the structural and conductivity relaxation occurs on roughly the same time scale.

A capacitance manometer has been utilized to determine equilibrium water partial pressures and salt solubilities in aqueous NH4HSO4 over low temperature ranges. Measured pressures above the H2SO4 solution are consistent with values calculated using the procedure of Clegg et al, while results for the NH4HSO4 solutions also agree with calculated equilibrium water partial pressures. Solids form in the NH4HSO4 solutions at temperatures 258.0(sub 6) plus or minus 0.1 K, 246.4(sub 7) plus or minus 0.1 K and 261.0(sub 1) plus or minus 0.1 K.

The electrosynthetic approach has been found to be a convenient method in the reactions of two ketones and two alkenes leading to the formation monothianthrenium and bisthianthrenium salts. The selectivity to mono- or bisthianthrenium is proposed to be governed by the oxidation potential of the intermediate distonic radical cation. A single-crystal X-ray structure of the bisthianthrenium salt is also reported for the first time.

The monocarbonyl iodonium ylide is moderately nucleophilic in nature and undergoes stereoselective alkylidene transfer reaction to the C=N bond of the activated aldimines, affording 2-acylaziridines in good yields. This was gleaned from the results of an addition reaction of the monocarbonyl iodonium ylide to imines, which offers a stereoselective route for the synthesis of trans- and cis-2-acylaziridines. The stereochemical outcome of the aziridination was revealed to be dependent on both the activating groups of the imines and the reaction solvents.

A brown and red form of the [K-([2.2.2]crypt)]+ salts of naked polyhedral nonagermanide anions were isolated by dissolving the alloy K4Ge9 in ethylenediamine. Results of single-crystal x-ray structure analyses revealed that nonagermanide clusters do not have a strong correlation between observed structures and electron counts with respect to Wade rules. Crystal packing and influences by disordered solvent molecules had a significant effect on the arrangement of atoms and on the electronic properties.

A study was conducted on the controlled mono- and diprotonation of the [CO4O4](super 4+) cubane core. Products of the reactions were characterized by crystallographic and spectroscopic studies in solution. Structural effects of protonation were observed, and the core volume increased by approximately 2 and 6% on mono- and diprotonation, respectively. The diprotonated complexes exhibited behavior like that of H2SO4 in aqueous solution.

Inorganic and organic salts of the cyanophosphonate dianion and the monoanion of ethyl cyanophosphonate have been synthesized through novel methods employing the deethylation of diethyl cyanophosphonate. The new procedures used iodotrimethylsilane instead of bromotrimethylsilane as the silyldealkylating reagent. The inorganic salts were easily prepared by the reaction of hydroxides such as NaOH and NH4OH. The organic salts were obtained by adding amines to solutions of cyanophosphonic acid or by reaction of a hydroxide of a quaternary ammonium cation with cyanophosphonic acid.

The tris(trifluoromethanesulfonyl)methide anion has been prepared through a two-step process. The anion has been synthesized as its cesium salt, using triflic anhydride as the electrophilic trifyl source. The corresponding ytterbium(III) and scandium(III) salts have also been synthesized and their use in the aromatic nitration of o-nitrotoluene with ytterbium(III) and scandium(III) triflates have been assessed. The triflide anion has been found to increase the activity of the triflide salts compared with the triflates in the aromatic nitration of the electron deficient arene o-nitrotoluene.

Three new 'lower molar ratio' double salts of silver acetylide with silver nitrate were synthesized and their crystal structures determined. These are Ag2C2*5.5AgNO3*0.5H2O, Ag2C2*5AgNO3 and Ag2C2*AgNO3, wherein the acetylide dianion is located inside a silver cage shaped like a monocapped pctahedron, a monocapped trigonal prism and an octahedron, respectively. This series of related complexes adopted different structural alternatives, which indicate that a higher molar composition of silver acetylide in a double salt prefers the formation of a network of edge- and vertex-sharing silver polyhedra that closely resemble the structure of neat silver acetylide.

Ambient temperature AlCl3-ImCl (1-ethyl-3-methylimidazolium chloride) molten salts were observed to allow the systematic study of redox behavior of centered hexanuclear zirconium halide clusters in solution. The cyclic voltammetric data gathered showed a correlation between the oxidation potentials and the cluster charge. The stabilities of cluster species obtained through electrochemical oxidation were generally in agreement with scattered observations from preparative studies.

The halogenated carboxonium salts were isolated for the first time. Addition of dichloromethylmethylether to the superacidic media HF/MF5 (M = As, Sb) resulted in the production of the alkylidene oxonium salts CH3OCHX+MF6- (X = F, Cl). The salts were characterized by their low-temperature infrared and Raman spectra. The crystal structures of the hexafluoroantimonates were observed to vary in the major details.

A study was conducted to analyze the translation encounter between ionic salts and nitroxide free radicals in aqueous solution. Relaxation time measurements were carried out as a function of magnetic field strength. The pH was adjusted based on the aliquots of dilute acid or base. Results indicated that magnetic relaxation data is not enough to generate a detailed characterization of local electrostatic fields between solutes.

A study was conducted to analyze the catalysis of insertion reactions by metal salts. The insertions were carried out stereospecifically, high chemoselectivity and with complete regioselectivity in the case of unsymmetrical silacyclopopanes. Findings showed that the reactions of carbonyl insertion correlated with a mechanism supported transmetalation of silicon to copper. Results also indicated that formamides reacted faster than enals, which reacted faster than enoates.

A study was conducted to analyze novel molten salts based on polyether-tailed counterions. The counterions supported by the salts were ruthenium hexamine, metal trisbipyridines, metal trisphenanthrolines and ionic types of aluminum quinolate, porphyrins and anthraquinone. The Solartron Model SI I260 Impedance Analyzer was utilized to determine the ionic conductivities of the melt films. Cyclic voltammetry was then carried out using a low-current potentiostat.

The thermodynamic excess functions of solutions of strong electrolytes and their structure are described by an extension of the mean spherical approximation (MSA). Ionic association is also taken into account by means of Wertheim's formalism(super 18,19) in the MSA(super 20-24). Hydration effects are included using a concentration-dependent cation size and permittivity. The results show a very good representation for a number of mixed salts with a common cation. Cross parameters are introduced for salts without a common cation.

Research was conducted to examine the novel isomerization reaction of N,N-dimethyl-alpha-(methoxycarbonyl)-4-substituted-benzylammonium N-methylides with cesium fluoride. The reaction yielded two Stevens rearrangement products, namely methyl 3-(dimethylamino)-2-(4-substituted phenyl)propionates from N-methylides and methyl 3-(dimethylamino)-3-(4-substituted pphenyl)propionates from N-benzylides. When the cesium flouride used was not predried, additional Stevens rearrangement products were competitively formed from ylides.

The reaction of octachlorodirhenate with a redox-active tetrathiafulvalene phosphine ligand was investigated. Experimental results showed that the reaction produces the mixed-nuclearity paramagnetic salt (ReCl2(omicron-P2)2)(Re2Cl6(omicron-P2)) consisting of the mononuclear Re(super III) complex and the mixed-valence Re(super II)-Re(super III) dinuclear anion. The salt provides new information on the reaction pathway of (Re2Cl8)(super 2-) with diphosphine ligands.

The reactivities of a number of onium salts derived from 1-hydroxybenzotriazole and 1-hydroxy-7-azabenzotriazole were correlated with the structure of the reagents in question. Results verified that the aza derivatives are more reactive than the parent benzotriazole derivatives in both activation and coupling. Moreover, the activation step was determined by the structure of the carbon skeleton. The pyrrolidino derivatives were apparently preferred reagents compared to the piperidino analogues.

Research was conducted to examine the salt effects on binding and protein titration using a cavity-function theory for chemical association obtained with the exponential approximation. The coupling between the electrostatic interaction and hard-core interaction are investigated. Results indicate that the analytic theory more accurately predicts the electrostatic interaction factors measured in protein-titration experiments than the Debye-Huckel approximation theory.

A study was conducted to analyze the interaction between uncharged polymers and ionic surfactants in dilute aqueous solution using isothermal titration microcalorimetry. The 2277 TAM Thermal Activity Monitory system was utilized to carry out calorimetric measurements in a high-precision thermostatic bath. Experimental results indicated that the presence of extra salt and polarity of counterions influenced the interaction between polymers and surfactants.

A study was conducted to investigate the effects of 0.05% CaCl2, MgCl2 or ZnCl2 with or without 0.4% sodium tripolyphosphate in 10% or 30% fat, model beef batters. Results of the experiment which are discussed indicate among other things that 0.05% MgCl2 in the presence of 0.4% sodium tripolyphosphate in high added water systems where proteins and NaCl are diluted result in enhanced myosin and actomysin interactions with water.

The unique characteristics of 4,8-bis[bis(diethylamino)methylene]-1,2,3,5,6,7-hexaselenacyclooctane (4) were investigated. X-ray diffraction analysis was employed to determine the structure and reactivities of 4 as the 2,2-bis(diethylamino)-2-ethylium-1-diselenocarboxylate (3) equivalent as well as the spectroscopic evidence for the formation of 3 in solution. Results showed that 3 and 4 display similar behaviors toward a range of reagents and that 4 dissociates into 3 in solution.

A study was conducted to analyze the influence of salt and nonelectrolyte stress on the growth of Lactobacillus plantarum. The R 3010 quadrupole mass spectrometer was utilized to record electrospray mass spectra while L. plantartum cells were determined on cellulose actetate filters. Results indicated that severe growth inhibition correlated with the inability of cells to accommodate K+ to levels needed to restore turgor.

New seven-coordinated SbF7(super 2-) and BiF7(super 2-) dianions were isolated and characterized. BiF5 was then reacted with alkali metal fluorides at 250 degrees C to produce the salts Na2BiF7, K2BiF7, Rb2BiF7 and Cs2BiF7. The reaction of excess N(CH3)4F with BiF5 in CH3CN solution at -31 degrees C yielded the {N(CH3)4}2BiF7 salt. Moreover, the reaction of BiF5 and a substantial quantity of liquid FNO at -78 degrees C produced the salt (NO2)2BiF7, which subsequently decomposed to NOBiF6 and FNO.

The size of the alkali metal cation and the donor solvents used for crystallization determine the structural motif found in molecular species of heavier congeners of alkali metal phosphides. This was gleaned from a study of the structural aspects of several systems of heavier alkali metal congeners of supermesitylphosphane with regard to structural changes that are produced from alkali metal cation/solvent combinations used in the crystallization process. The molecular structural determinations of a number of different rubidium and cesium derivatives of supermesitylphosphane are reported.

Research was conducted to examine procedures for the enantioselective synthesis of functionalized aminocyclopentenes and their application to the preparation of biomedically relevant cyclic and acyclic targets. The procedure developed for the synthesis of (+)-mannostatin A was modestly concise and economical in addition to its ability to highlighting the preparative utility of pyridinium salt photochemistry. It was also observed to have the flexibility necessary for the preparation of various regiochemical and stereochemical analogues of the natural product.

Research was conducted to examine the role of neopentyl 3-triflyloxypropanesulfonate, a reactive sulfopropylation reagent for the preparation of chemiluminescent labels. Neopentyl 3-triflyloxypropanesulfonate was easily prepared and was observed to be much more reactive than 1,3-propane sultone in the preparation of sterically hindered sulfopropylated acridinium chemiluminescent labels. It is also expected that this reactive sulfopropylating reagent will be of use in the functionalization of heterocyclic bases.

Research was conducted to examine the magnetic structures of the layer ferrimagnets P(C6D5)4MIIFe(C2O4)3 (MII = Mn, Fe) by neutron powder diffraction. The MnFe compound and the FeFe compound were both fitted with a Gaussian peak shape and R3c unit cell. The intensity not fitted by the profile matching method was attributed to a small fraction of P6(3) stacking phase identified in X-ray diffraction profiles. Results indicate contrasting low-temperature magnetic order in the bimetallic layer ferrimagnets.

Research was conducted to demonstrate that O2+ salts generate stable solutions of dissolved O2F with alkali fluoride in aHF, at -50 degrees C or below. Its solutions oxidize Ag(II) to Ag(III), Au(III) to Au(V) and Ni(II) to Ni(IV). The interaction of O2+ with Pt(IV) salts in aHF yields Pt(V). However, attempts to oxidize Pd(IV) to Pd(V) are not successful. Solutions of O2F in aHF are proven to be weakly basic.

The synthesis of tripolar bis(hetarenio)pyrimidin-4-olates and some of their alkylated dicationic derivatives were investigated. Chlorine displacement reactions between tetrachloropyrimidine and nucleophilic heteroaromatics proceeded smoothly and yielded (5-chloropyrimidin-2,4,6-triyl)trishetarenium salts. Computations were performed on a representative compound to assess the classification of the pyrimidin-4-olates as hybrids between cross-conjugated mesomeric betaines and hetarenium salts.

The reaction of appropriate halides with (NH4)3(S2CSCH2CH(NHCS2)CO2) was conducted for the preparation of a novel series of organogermanium derivatives. As shown by nuclear magnetic resonance spectroscopy, CS2 elimination and rearrangement during decomposition of the trimethylgermane derivative afforded Me3GeO2C(-CHNHC(S)SCH2-). The latter's molecular structure suggests a dimeric structure with a hydrogen bond from NH to the terminal C=O.

The mean spherical approximation (MSA) model was used to study the osmotic and activity coefficients for aqueous solutions of pure associating electrolytes. The binding MSA was used to examine the association of ions of opposite charges for a variety of solutions of pure salts. Results showed that good fits can be obtained in some solutions of very high concentrations. A description for sulphuric acid was also obtained at low concentration.

The dependence of stability effect of protein salt-bridges on variations in the atomic parameters and the treatment of the dielectric change at the molecular boundary was investigated using continuum calculations. Results showed that the largest desolvation penalties were produced by approximation of the molecular surface, while smallest was produced by the smoothed boundary. The various parameter sets wee also found to produce relatively similar energetics, which is partly due to compensating effects.

Syntheses, structures, and properties of radical salts made with bis(ethylenedithio)tetrathiafulvalene (ET) and monosubstituted alpha-Keggin polyoxoanions are described. Crystallization of salts occur in two series. Alternating layers of the organic donor and Keggin polyoxometalates appear in the general structure. An eclipsed chain with almost totally ionized ET molecules and a dimerized one with partially charged ET molecules form the organic layers. Magnetic behaviors exhibited by salts with discrete magnetic anions relate to the sum of the magnetic contributions of the two lattices.

The synthesis, properties, and reactivity of N,N'-difluorobipyridinium and related salts are presented. Synthesization was conducted using direct fluorination in a step-by-step manner of a mixture of a bipyridyl and a Lewis acid, a Bronsted acid or the alkali metal salt of an acid. results indicate that N,N'-difluoro-2,2'-bipyridinium bis(tetrafluoroborate) is a highly reactive electrophilic fluorinating agent with high effective fluorine content.

A study was conducted to examine the hydrolysis reactions of 2-deoxy-alpha-D-glucopyranosyl pyridinium salts. Second-order rate constants were computed for the reactions while two diastereotopic aspects of the reaction intermediate was considered to determine nucleophilic attacks. Results indicated that the 2-deoxyglucosyl oxocarbenium ion was not solvent-equilibrated in water. Findings also showed that solvent reactions occurred about 2-fold faster with the cationic intermediate.

A study was conducted to examine the use of iminium salts to determine the catalytic asymmetric epoxidation of alkenes by Oxone. Bromine was added through a reflux condenser for vigorous reaction subsides while amine was dissolved in an ethanol solution. Results indicated that the catalytic procedure is very easy to use and does not need the support of chromatography and double bond stereochemistry.

A study was conducted to analyze the H/D isotope effects on nitrogen-hydron distances and 15N chemical shielding tensors of hydrogen bonded-bisiscoyanide salts. The effects of the low-barrier hydrogen bond of polycrystalline was also examined in the study. Results indicated the chemical shielding of the nuclei in the hydrogen bridge was a qualitative probe for primary and secondary geometric isotope effects.

Research was conducted to study the photochemical reactions of hydrocarbons by nitropyridinium salts. A mixture of pyridine derivatives and trimethyl or triethyloxonium tetrafluoroborate was stirred at room temperature while photochemical reactions were performed in a reactor equipped with a high pressure Hg lamp. Results indicated that hydrocarbon chains with different types of substituents can be oxidized by photoactivated nitropyridinium salts.

The heterogeneous reactions of nitryl halides with aqueous salt solutions as a model substrate for atmospheric sea salt aerosol were investigated. The reaction of Br2 with nitrite solution was found to be a convenient approach to the synthesis of BrNO2. The heterogeneous reactions result in the formation and loss of BrNO2 on salt solutions. The temperature-dependent lifetime of BrNO2 in a quartz cell was measured and the activation energy for the unimolecular decay at atmospheric pressure was obtained.

Research was conducted to examine the voltammetric oxidation of solution and solid phases of salts of (V/(CO)6-) in aqueous (electrolyte) media. The starting material was sodium diglyme and stabilized salt and experiments were confined to the potential region associated with the process. Results indicate that V(CO)6 in solution reacts with water as well as with oxygen. However, the product of electrochemical oxidation reacts slowly with water but very rapidly with oxygen on the voltammetric time scale.