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Butenolide Synthesis Via Cation-Initiated Ring Expansion/Elimination Of Β-Lactones, Jianhua Huang Jan 1992

Butenolide Synthesis Via Cation-Initiated Ring Expansion/Elimination Of Β-Lactones, Jianhua Huang

Masters Theses

An area of recent research in the Black research group is an exploration of the potential of cation-initiated β-lactone ring expansions, accompanied by the elimination of a proton or other electrofuge, as a protocol for the synthesis of multisubstituted butenolides.

Γ-Bromo β-lactones were prepared via bromolactonization of the appropriate β,Γ-unsaturated acids under basic conditions. The nucleofugal bromine atom on the Γ-carbon was then employed to effect carbocation formation adjacent to the lactone ring oxygen atom; the most efficacious reagent combination was found to be silver nitrate in refluxing acetic acid. Generation of this cation initiated a migration of the β-lactone …


A Proposal For United States/Polish Collaboration On Energy And The Environment, Carole B. Szpunar Jan 1992

A Proposal For United States/Polish Collaboration On Energy And The Environment, Carole B. Szpunar

Chemistry: Faculty Publications and Other Works

Argonne National Laboratory, a U.S. Department of Energy facility that is operated by the University of Chicago and located southwest of Chicago, Illinois, has proposed a collaborative effort by the United States and Poland to conduct applied research on energy and environmental topics of common interest. Through this collaboration, evaluative studies on energy and environmental assessment issues could be developed and implemented by Argonne and one or more sister institutions in Poland, which could lead to active research, development, and demonstration joint activities. The objective of this initiative is to produce strategies and options for review by Poland's decision makers …


New Reaction Conditions For The Synthesis Of Wieland-Miescher Ketone, Jonathan J. Bates Jan 1992

New Reaction Conditions For The Synthesis Of Wieland-Miescher Ketone, Jonathan J. Bates

Presidential Scholars Theses (1990 – 2006)

Natural products chemistry is a very important field of chemistry to chemists, biochemists, and biologists. The ability to synthesize a naturally occurring chemical in the laboratory is necessary for some experiments. Often it is difficult to isolate a large quantity of a compound from its natural source when needed for certain experiments. Established procedures for artificial synthesis of this compound can produce higher yields. Sometimes, the function of a natural product is tested by observing the behavior of analogues in the same biological system. The differences in behavior can be related to differences in structure . Since such analogues are …


Improved Recovery Of A Radlolabeled Peptide With An Albumin-Treated Reversed-Phase Hplc Column, David S. Hage, Robert L. Taylor, Pai C. Kao Jan 1992

Improved Recovery Of A Radlolabeled Peptide With An Albumin-Treated Reversed-Phase Hplc Column, David S. Hage, Robert L. Taylor, Pai C. Kao

David Hage Publications

Reversed-phase high-performance liquid chromatography (RP-HPLC) is an important tool in the purification of radiolabeled peptides and proteins for immunoassay. However, for some proteins and peptides it is difficult to achieve reproducible behavior in RP-HPLC because of the low recovery of these compounds. Factors that can be varied to improve recovery include the strength or pH of the mobile phase, the chain length and spacing of groups on the reversed-phase support, and the flow rate or steepness of the elution gradient (1-5). ... In summary, we obtained better recovery and more reproducible chromatographic behavior for labeled 1-34 PTHrP with an albumin-pretreated …


Intact Parathyroid Hormone: Performance And Clinical Utility Of An Automated Assay Based On High-Performance Immunoaffinity Chromatography And Chemiluminescence Detection, David S. Hage, Bob Taylor, Pai C. Kao Jan 1992

Intact Parathyroid Hormone: Performance And Clinical Utility Of An Automated Assay Based On High-Performance Immunoaffinity Chromatography And Chemiluminescence Detection, David S. Hage, Bob Taylor, Pai C. Kao

David Hage Publications

The performance and clinical utility of an automated assay of intact parathyroid hormone (parathyrin, PTH) are evaluated. The method is based on the extraction of PTH from plasma by an HPLC column containing immobilized anti-(44-68 PTH) antibodies. The PTH retained is detected with a postcolumn reactor and use of anti-(1--34 PTH) chemiluminescent-labeled antibodies. The total cycle time of the assay is 6.5 mm per injection after a 1-h incubation.The lower limit of detection for PTH in a 66-pL plasma sample was 0.5 pmol/L based on peak heights and 0.2 pmol/L based on peak areas. Mean analytical recovery for PTH added …


Studies On Improving The Regioselectivity Of Reactions Of Sucrose: The Role Of Molecular Recognition And Polymer Supported Syntheses, Ran Jiang Jan 1992

Studies On Improving The Regioselectivity Of Reactions Of Sucrose: The Role Of Molecular Recognition And Polymer Supported Syntheses, Ran Jiang

Masters Theses

The world economy is critically dependent upon natural resources. Because sucrose can be inexpensively produced in large quantities and refined to a purity unequalled by almost all other natural products, it has been exploited as an industrial raw material for many years, primarily as a sweetener. A major difficulty in utilizing sucrose as an industrial feedstock is the lack of regioselectivity in synthetic reactions due to its eight hydroxyl groups of similar reactivity.

The long range goal in this work is to apply the technique of molecular recognition by template imprinting to the creation of a material that will bind …


Remote Dianions In The Synthesis Of Indolizidine Alkaloids, Diana L. C. Green Green Jan 1992

Remote Dianions In The Synthesis Of Indolizidine Alkaloids, Diana L. C. Green Green

Dissertations

No abstract provided.


The Synthesis Of Chiral Building Blocks Using Beta-Hydroxy Sulfoxide Dianions, Carla M. Edwards Jan 1992

The Synthesis Of Chiral Building Blocks Using Beta-Hydroxy Sulfoxide Dianions, Carla M. Edwards

Master's Theses

No abstract provided.


Syntheses Of Azure-B Neuropeptide Conjugates And A Novel Bicyclic Triene, Milind D. Choubal Jan 1992

Syntheses Of Azure-B Neuropeptide Conjugates And A Novel Bicyclic Triene, Milind D. Choubal

Dissertations

No abstract provided.


Resonance Raman Spectra Of Chloroperoxidase Reaction Intermediates, Ann Marie G. Sullivan Jan 1992

Resonance Raman Spectra Of Chloroperoxidase Reaction Intermediates, Ann Marie G. Sullivan

Theses and Dissertations

Chloroperoxidase is an enzyme that exhibits spectroscopic and structural properties similar to cytochrome P-450. Chloroperoxidase is studied using resonance Raman spectroscopy to characterize the reaction intermediates of the physiological mechanism, known as compounds I and II. Compound I is formed by a two electron oxidation of the resting enzyme and contains an Fe(IV) porphyrin ℼ cation radical. A one electron reduction of compound I produces the compound II intermediate which contains an oxy-ferryl [Fe(IV)=O] iron heme.

Chloroperoxidase is a heme enzyme of substantial interest because of its structural similarity to cytochrome P-450 and because of its diverse reactivity. Chloroperoxidase can …


Structure Of (22S)-3Β-Acetoxy-20-(3-Isopropylisoxazolin-5-Yl)-4,4,14 Α-Trimethylpregn-8(9)-Ene, Sergey V. Lindeman, Mikael S. Alexanyan, Yuri T. Struchkov, Rajesh Kumar Thaper, Irina G. Reshetova, Alexey V. Kamernitzky Jan 1992

Structure Of (22S)-3Β-Acetoxy-20-(3-Isopropylisoxazolin-5-Yl)-4,4,14 Α-Trimethylpregn-8(9)-Ene, Sergey V. Lindeman, Mikael S. Alexanyan, Yuri T. Struchkov, Rajesh Kumar Thaper, Irina G. Reshetova, Alexey V. Kamernitzky

Chemistry Faculty Research and Publications

C32H51NO3, Mr = 497·7, orthorhombic, P212121, a = 7·577 (2), b = 10·510 (2), c = 35·399 (7) Å, V = 2819 (1) Å3, Z = 4, Dx = 1·173 g cm-3, λ (Mo Kα) = 0·71073 Å, μ = 0·69 cm-1, F(000) = 1096, T = 153 K, R = 0·0497 for 2235 observed reflections. The compound investigated is found to be a (22S)-epimer.


Experiments In Aerobic And Anaerobic Biodegradation Of Trichloroethylene, Qiong Liao Dec 1991

Experiments In Aerobic And Anaerobic Biodegradation Of Trichloroethylene, Qiong Liao

Theses

The removal of trichloroethylene (TCE) from industrial waste has been intensively studied in recent years, Biodegradation has been determined to be an effective treatment for TCE in the environment. Many researchers have studied the biodegradation of TOE and obtained successful results based on the use of specific isolated bacteria. At the NJIT Biotechnology Laboratory, a new method is being developed in which immobilized activated sludge is used to degrade several toxic chemicals in various reactor configurations. The objective of this research is to determine if these methods can be extended to treat TCE.

Activated sludge from a wastewater treatment plant …


Resolution Of Enantiomeric Hydrocarbon Biomarkers Of Geochemical Importance, Daniel W. Armstrong, Yubing Tang, Janusz Zukowski Dec 1991

Resolution Of Enantiomeric Hydrocarbon Biomarkers Of Geochemical Importance, Daniel W. Armstrong, Yubing Tang, Janusz Zukowski

Chemistry Faculty Research & Creative Works

Chlral isoprenoid and hydroaromatic compounds occur in all crude oils, coals, shales, and most sediments. Many of these compounds are referred to as biological markers since they are thought to be derived from biological sources and their presence, relative concentrations, or stereochemistry can provide information as to a geological deposit's age, maturity, diagenetic history, and so forth. Because of the previous lack of effective and efficient analytical methodologies for resolving hydrocarbon enantiomers, the stereochemical information encoded in these molecules is largely untouched. A series of derivatized α-, β-, and γ-cyclodextrin chiral stationary phases (CSPs) were used for the gas chromatographic …


Surface Structure Of √3x√3r 30 Cl/Ni(111) Determined Using Low-Temperature Angle-Resolved-Photoemission Extended Fine Structure, Li-Qiong Wang, Z. Hussain, Z. Q. Huang, A. E. Schach Von Wittenau, Dennis W. Lindle, D. A. Shirley Dec 1991

Surface Structure Of √3x√3r 30 Cl/Ni(111) Determined Using Low-Temperature Angle-Resolved-Photoemission Extended Fine Structure, Li-Qiong Wang, Z. Hussain, Z. Q. Huang, A. E. Schach Von Wittenau, Dennis W. Lindle, D. A. Shirley

Chemistry and Biochemistry Faculty Research

A surface structural study of the √3 × √3 R30° Cl/Ni(111) adsorbate system was made using low-temperature angle-resolved photoemission extended fine structure. The experiments were performed along two emission directions, [111] and [110], and at two temperatures, 120 and 300 K. The multiple-scattering spherical-wave analysis determined that the Cl atom adsorbs in the fcc threefold hollow site, 1.837(8) Å above the first nickel layer, with a Cl-Ni bond length of 2.332(6) Å, and an approximate 5% contraction between the first and the second nickel layers (the errors in parentheses are statistical standard deviations only).


Consumption Rates, Evacuation Rates And Diets Of Pygmy Killifish, Leptolucania Ommata, And Mosquitofish, Gambusia Affinis In The Okefenokee Swamp, J. Douglas Oliver Dec 1991

Consumption Rates, Evacuation Rates And Diets Of Pygmy Killifish, Leptolucania Ommata, And Mosquitofish, Gambusia Affinis In The Okefenokee Swamp, J. Douglas Oliver

Faculty Publications and Presentations

I studied feeding dynamics of Leptolucania ommata and Gambusia affinis in the Okefenokee Swamp. Both fishes mainly ate insect larvae (such as Chironomidae) and Cladocera. Evacuation rates ranged from 0.143 (L. ommala in winter) to 0.279/hour (L. ommala in summer). Daily food consumption (dry weight) ranged from 24.2 (L. ommata in winter) to 148.3 mg/g/day (G. affinis in summer). Maximum consumption by both species was estimated at 26.31 mg/t m2 / day, in summer. These values are consistent with other observations supporting a hypothesis that invertebrate prey production is substantial in these blackwater wetlands.


Ua66/7/2 Hilltopper News, Wku Chemistry Oct 1991

Ua66/7/2 Hilltopper News, Wku Chemistry

WKU Administration Documents

Newsletter created by and about the WKU Chemistry department.


Expression Of Biologically Active Human Corticosteroid Binding Globulin By Insect Cells: Acquisition Of Function Requires Glycosylation And Transport, Jayasri Ghose-Dastidar, J. B. Alexander Ross, Reza Green Aug 1991

Expression Of Biologically Active Human Corticosteroid Binding Globulin By Insect Cells: Acquisition Of Function Requires Glycosylation And Transport, Jayasri Ghose-Dastidar, J. B. Alexander Ross, Reza Green

Chemistry and Biochemistry Faculty Publications

Human corticosteroid binding globulin (hCBG) is a 50- to 55-kDa serum glycoprotein that binds cortisol and progesterone with high affinity. To map the steroid-binding domain and to investigate the folding pathways of hCBG, we have established an expression system based on infection of insect cells with a recombinant baculovirus encoding hCBG. Infected Spodoptera frugiperda (Sf9) cells secrete immunoreactive hCBG at high levels (16-24 pmol per 106 cells per 40 h), and the recombinant protein binds cortisol with an affinity and specificity equivalent to that of human serum-derived hCBG. Thus, this system has the potential to provide large amounts of …


Micellar Catalysis Of Hydrolysis Of Substituted Hydroxamic Acids With Perfluorooctanoic Acid, Zhongyuan He Aug 1991

Micellar Catalysis Of Hydrolysis Of Substituted Hydroxamic Acids With Perfluorooctanoic Acid, Zhongyuan He

Masters Theses

The work demonstrated the effects of differently located and substituted phenyl groups, as well as aliphatic groups in the hydroxamic acids, on micellar catalysis with perfluorooctanoic acid as the reactive counterion surfactant in aqueous acetonitrile solution.

Kinetic rate constant-surfactant concentration profiles for the decano-, 2,5-dimethylphenylaceto-, 4-isopropylphenylaceto-, 4-phenylbutano-, and 6-phenyl-hexanohydroxamic acids were examined and analysis on the data obtained were reported.

The pseudo-phase ion exchange (PPIE) model has been satisfactorily applied to explain the observed micellar effects.

Further investigation into more appropriately substituted hydroxamic acids is suggested in order to obtain a more complete set of data and further evaluation.


Measurement Of The Ratio Of Double-To-Single Photoionization Of Helium At 2.8 Kev Using Synchrotron Radiation, Jon C. Levin, Dennis W. Lindle, N. Keller, R. D. Miller, Y. Azuma, N. Berrah Mansour, H. G. Berry, Ivan A. Sellin Aug 1991

Measurement Of The Ratio Of Double-To-Single Photoionization Of Helium At 2.8 Kev Using Synchrotron Radiation, Jon C. Levin, Dennis W. Lindle, N. Keller, R. D. Miller, Y. Azuma, N. Berrah Mansour, H. G. Berry, Ivan A. Sellin

Chemistry and Biochemistry Faculty Research

We report the first measurement of the ratio of double-to-single photoionization of helium well above the double-ionization threshold. Using a time-of-flight technique, we find He++/He+=1.6±0.3% at hν=2.8 keV. This value lies between calculations by Amusia (2.3%) and by Samson, who predicts 1.2% by analogy with electron-impact ionization cross sections of singly charged ions. Good agreement is obtained with older shake calculations of Byron and Joachain, and of Åberg, who predict 1.7%.


Anisotropy Of Polarized X-Ray Emission From Molecules, S. H. Southworth, Dennis W. Lindle, R. Mayer, P. L. Cowan Aug 1991

Anisotropy Of Polarized X-Ray Emission From Molecules, S. H. Southworth, Dennis W. Lindle, R. Mayer, P. L. Cowan

Chemistry and Biochemistry Faculty Research

Strongly anisotropic, polarized Cl K-V x-ray emission from gas-phase CF3Cl has been observed following resonant excitation with a linearly polarized x-ray beam. Distinctively different angular distributions are observed for x-ray emission involving molecular orbitals of different symmetries. A classical model of the x-ray absorption-emission process accurately describes the observed radiation patterns.


Stable N-Chloraldimines And Other Chlorination Products Of Phenylalanine In Model Solutions And In A Wastewater, Barbara L. Conyers Jul 1991

Stable N-Chloraldimines And Other Chlorination Products Of Phenylalanine In Model Solutions And In A Wastewater, Barbara L. Conyers

Chemistry & Biochemistry Theses & Dissertations

Model solutions of the amino acid phenylalanine were chlorinated to seven Cl/N mole ratios. The by-products were characterized using gas chromatography, high performance liquid chromatography, GC/MS, infrared spectroscopy, and nuclear magnetic resonance spectroscopy. At the lower Cl/N ratios N-chlorophenylalanine and phenylacetaldehyde were identified as the main products while phenylacetonitrile and N-chlorophenylacetaldimine were the major products at Cl/N ratios of 2.0 and beyond. The concentration of phenylalanine in a municipal wastewater was determined. Using a radiotracer the chlorination products of phenylalanine in the wastewater at the 7 Cl/N ratios were identified as those seen in the model solutions. The distribution of …


Ua3/8/1 John Robinson Professorship Report, Wku Ogden College Of Science & Technology Jun 1991

Ua3/8/1 John Robinson Professorship Report, Wku Ogden College Of Science & Technology

WKU Administration Documents

Report by Dr. John Riley, John Robinson Professor of activities for 1990-1991 funded by Ogden Foundation.


Formation Of Pentosidine During Nonenzymatic Browning Of Proteins By Glucose, Daniel G. Dyer, James A. Blackledge, Suzanne R. Thorpe, John W. Baynes Jun 1991

Formation Of Pentosidine During Nonenzymatic Browning Of Proteins By Glucose, Daniel G. Dyer, James A. Blackledge, Suzanne R. Thorpe, John W. Baynes

Faculty Publications

A fluorescent compound has been detected in proteins browned during Maillard reactions with glucose in vitro and shown to be identical to pentosidine, a pentose- derived fluorescent cross-link formed between arginine and lysine residues in collagen (Sell, D. R., and Monnier, V. M. (1989) J. Biol. Chem. 264, 21597- 2 1602). Pentosidine was the major fluorophore formed during nonenzymatic browning of ribonuclease and lysozyme by glucose, but accounted for <1% of nondisulfide cross-links in protein dimers formed during the reaction. Pentosidine was formed in greatest yields in reactions of pentoses with lysine and arginine in model systems but was also formed from glucose, fructose, ascorbate, Amadori compounds, 3-deoxyglucosone, and other sugars. Pentosidine was not formed from peroxidized polyunsaturated fatty acids or malondialdehyde. Its formation from carbohydrates was inhibited under nitrogen or anaerobic conditions and by aminoguanidine, an inhibitor of advanced glycation and browning reactions. Pentosidine was detected in human lens proteins, where its concentration increased gradually with age, but it did not exceed trace concentrations (55 Fmol/mol lysine), even in the 80-year-old lens. Although its precise carbohydrate source in vivo is uncertain and it is present in only trace concentrations in tissue proteins, pentosidine appears to be a useful biomarker for assessing cumulative damage to proteins by nonenzymatic browning reactions with carbohydrates.


Decrease In Skin Collagen Glycation With Improved Glycemic Control In Patients With Insulin-Dependent Diabetes Mellitus, Timothy J. Lyons, Karen E. Bailie, Daniel G. Dyer, John A. Dunn, John W. Baynes Jun 1991

Decrease In Skin Collagen Glycation With Improved Glycemic Control In Patients With Insulin-Dependent Diabetes Mellitus, Timothy J. Lyons, Karen E. Bailie, Daniel G. Dyer, John A. Dunn, John W. Baynes

Faculty Publications

Glycation, oxidation, and nonenzymatic browning of protein have all been implicated in the development of diabetic complications. The initial product of glycation of protein, fructoselysine (FL), undergoes further reactions, yielding a complex mixture of browning products, including the fluorescent lysine-arginine cross-link, pentosidine. Alternatively, FL may be cleaved oxidatively to form N(epsilon)-(carboxymethyl)lysine (CML), while glycated hydroxylysine, an amino-acid unique to collagen, may yield N(epsilon)-(carboxymethyl)hydroxylysine (CMhL). We have measured FL, pentosidine, fluorescence (excitation = 328 nm, emission = 378 nm), CML, and CMhL in insoluble skin collagen from 14 insulin-dependent diabetic patients before and after a 4-mo period of intensive therapy to …


Nonlinear Optical Properties Of Bacteriorhodopsin: Assignment Of The Third-Order Polarizability Based On Two-Photon Absorption Spectroscopy, Robert R. Birge, Mark Masthay, Jeffery A. Stuart, Jack R. Tallent, Chian-Fan Zhang Jun 1991

Nonlinear Optical Properties Of Bacteriorhodopsin: Assignment Of The Third-Order Polarizability Based On Two-Photon Absorption Spectroscopy, Robert R. Birge, Mark Masthay, Jeffery A. Stuart, Jack R. Tallent, Chian-Fan Zhang

Chemistry Faculty Publications

The third-order (pi) -electron polarizability, (gamma) (pi), of bacteriorhodopsin in the 0.0 - 1.2 eV optical region is assigned based on an analysis of the experimental two-photon properties of the low-lying singlet state manifold. The following selected values of (gamma) (pi) (units of 10-36 esu) are observed: (gamma) (0;0,0,0) equals 2482 +/- 327; (gamma) (-3(omega) ;(omega) ,(omega) ,(omega) ) equals 2976 +/- 385 ((omega) equals 0.25 eV), 5867 +/- 704 ((omega) = 0.5 eV), 14863 +/- 1614 ((omega) = 0.66 eV), 15817 +/- 2314 ((omega) equals 1.0 eV), 10755 +/- 1733 ((omega) equals 1.17 eV). The third-order polarizability of this …


Methods Development For Determination Of Trace Polar Volatile Organics In Environmental Samples, Qingchu Peng May 1991

Methods Development For Determination Of Trace Polar Volatile Organics In Environmental Samples, Qingchu Peng

Theses

The determination of trace levels of organic compounds in water samples is well developed for the less polar compounds, but the polar compounds are more difficult. The development of reliable and reproducible methods for such compounds as volatile alcohols and ketones is necessary if environmental monitoring is to be extended to these compounds.

The purge-and-trap method is frequently used for determination of volatiles in water samples. The method has problems when hydrophylic substances are being analyzed, since these are less easy to purge from the solution and more difficult to trap and desorb quantitatively. The high amount of water carried …


The Limitations Of Women In Science At Six Midwestern Colleges Due To The Adherence To Conceptions Of Gender Differences Between The Sexes In The Years Of 1880 Through 1940, Denise Mohney '91 Apr 1991

The Limitations Of Women In Science At Six Midwestern Colleges Due To The Adherence To Conceptions Of Gender Differences Between The Sexes In The Years Of 1880 Through 1940, Denise Mohney '91

Honors Projects, History

It is difficult for college students today to imagine life when the term "discrimination" had not yet been defined or conceived. Yet only a little more than a hundred years ago women were first entering the academic world alongside men. These were often middle class women whose primary interactions with men had been through courtship and marriage. It was questioned whether women's intellectual ability and physical stamina were strong enough to persevere through the college experience. Scientists and physicians, writing for the general public, cited evidence that besides physical distinctions between the sexes, there were also intellectual and emotional differences. …


Electrostatically Paired Porphyrin And Phthalocyanine: Equilibria And Electrochemical Oxidation, Libin Ho '91 Apr 1991

Electrostatically Paired Porphyrin And Phthalocyanine: Equilibria And Electrochemical Oxidation, Libin Ho '91

Honors Projects

A synthetic model system for the special pair in the photosynthetic reaction center of bacteria has been prepared from electrostatically paired porphyrin and phthalocyanine molecules. Use of rigorously dry propylene carbonate as the solvent allowed complex fonnation to occur between tetra-(N-methyl-4-pyridyl)porphyrin hexafluorophosphate (H2TMPyP(PF6)4) and tetraphenylphosphonium tetrasulfatophthalocyanine (Ph4P)4H2TSPc molecules. The stoichiometry of the complex was determined to be 1:1 by Job's method and the pair formation constant K1 was estimated to be 1x108.T he dependence of K1 on ionic strength was studied at various concentrations of tetra-n-butylammonium tetrafluoroborate BU4NBF4. With increasing ionic strength K1 decreases as expected according to the Debye-Huckellimiting …


Synthesis And Characterization Of An 18-Membered Macrocyclic Ligand Containing 2,2-Biimidazole For Selective Binding Of Transition Metal Ions, Mark Barnett Apr 1991

Synthesis And Characterization Of An 18-Membered Macrocyclic Ligand Containing 2,2-Biimidazole For Selective Binding Of Transition Metal Ions, Mark Barnett

Opportunities for Undergraduate Research Experience Program (OURE)

A description of the synthetic approach to the preparation of an 18 membered macrocyclic ligand containing 2/2'-biimidazole is presented. A diol derivative of 2,2'-biimidazole is tosylated with p-toluene sulfonyl chloride making it susceptible to bimolecular substitution with a disodium salt of tetratosylated triethylenetetraamine. The final desired product is an 18N6 macrocycle, 4,7-(l,l'-(2,2'-biimidazolo))-l,4,7,10,13,16-hexaazacyclooctadecane, potentially capable of binding transition metal ions in various combinations with three chelating sites. Initial characterization includes NMR and IR spectroscopic analysis.


An Analysis Of Dissolved Organic Compounds And Their Contribution To Iron Complexation In The Shallow Leachate Plume Of The West Kl Landfill Kalamazoo, Michigan, Eric Fahle Apr 1991

An Analysis Of Dissolved Organic Compounds And Their Contribution To Iron Complexation In The Shallow Leachate Plume Of The West Kl Landfill Kalamazoo, Michigan, Eric Fahle

Masters Theses

High concentrations of dissolved iron are present in downgradient groundwater samples adjacent to the western border of the West KL Landfill. Analysis by Rudder (1988) of groundwater samples indicates oversaturation of selected iron oxides, iron sulfides and siderite in monitoring wells TW-4 and M3.

Previous research suggests that pyrogallol, gallic acid, tannic acid and similar organic compounds may retard the oxidation of ferrous iron in the shallow leachate plume of the West KL landfill (Rudder, 1988). Present research utilizing solid phase extraction, reverse phase high performance chromatography, Fourier transform IR spectrophotometry, UV/Visible spectrophotometry, and gas chromatography/mass spectroscopy indicate that pyrogallol, …