Chemistry (Alabama Undergraduate Research Symposium) posters abstracts.

Butamben Synthesis: The Fischer Esterification reaction revisited. Nagarajan Vasumathi, Haley Booker and Christopher Goodwin, Dept. of Physical and Earth Sciences, Jacksonville State University, Jacksonville, AL 36265.

Esters of p-aminobenzoic acid (PABA), a class of analgesics are prepared by Fischer Esterification, a method, commonly employed for the synthesis of esters. This method is known to yield poor yields because it is an equilibrium reaction and also due to complexity in product isolation. Techniques to better synthesize pure samples of these compounds are still under research. As a model study, we undertook the synthesis of Butamben, the butyl ester of PABA, an analgesic known to alleviate neuropathic pain for longer period and more selectively. The removal of water, a by-product in the reaction, from the system was the biggest concern, and heavily affected the course of the reaction. Applying Le Chatlier's principle, different methods were attempted not only to improve the yield but also to achieve the isolation of much purer product. Using a Dean-Stark apparatus (glassware designed especially for the removal of water from the system as the reaction proceeds) as a tool, a better yield and purer product was obtained with reduced reaction time. The product was identified and characterized by IR and NMR spectral analysis which showed 99% purity. The modified method of synthesis, isolation, purification and characterization are discussed. The new, improved method will be extended to synthesize other derivatives of PABA that could be optically active. Further exploration to study the effect of other catalysts on the reaction is also underway.

Development of a Quantitative Analytical Method for the Simultaneous Detection of Mixtures of n-Alkanethiols by Mass Spectrometry. Rachel Roberts and Brian W. Gregory, Department of Chemistry & Biochemistry, Samford University, Birmingham, AL 35229-2236.

A method is currently being developed for the quantitative analysis of mixtures of n-alkanethiols [(R(C[H.sub.2]).sub.m] SH, where m = 1,2,3,..., and R = C[H.sub.3], HO, HOOC, etc.) in solution by mass spectrometry. The purpose of this method is not only to be able to differentiate between different alkanethiols in solution mixtures, but also to be able to determine the relative amount of each type of alkanethiol that is present. Both electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI) are being investigated as a means to generate the alkanethiols as gas-phase ions for detection by mass spectrometry. These studies are part of a wider project involving the study of multi-component alkanethiol self-assembled monolayers (SAMs), which consist of two or more different types of alkanethiols adsorbed as a single monomolecular film on metal surfaces. The overall goal of this portion of the project is to use mass spectrometry as a means of determining the surface mole fractions of the alkanethiol components contained in mixed SAMs as a function of their solution mole fractions. Preliminary data involved in the development of the mass spectrometric method for this analysis will be presented. Acknowledgements: This work was supported by a Major Research Instrumentation (MRI) grant from the National Science Foundation (Grant No. 0619217, BWG) and by the Samford University Summer Undergraduate Research Program (RR).

HEAVY METAL CONTAMINATION IN SOILS AROUND ANNISTON, ALABAMA. Nixon Mwebi, Bryan DeLauney, Department of Physical & Earth Sciences, Jacksonville State University, 700 Pelham Rd. N, Jacksonville, AL 36265.

For the past several decades, Anniston Alabama has been a largely industrial town and a number of these manufacturing industries relied on heavy metals such as arsenic and cadmium in the processing of various products. Despite their usefulness, cadmium and arsenic has been labeled as a carcinogen with harmful effects to both humans and animals. The danger of exposure to the heavy metals lies in the method of exposure of the metal waste, which in the past has largely been in land fills with non-impermeable linings. In such instances, there is the potential of the metal leaching out leading to possible exposure to humans and animals through food, water and air. Effective monitoring of these carcinogens is therefore needed and in this study, levels of arsenic and cadmium around an abandoned manufacturing site in west Anniston, Alabama are determined and their potential for leaching and movement downhill explored.

Solvent and catalytic effects on the addition of bromine to DMME. Nagarajan Vasumathi, Nixon Mwebi, Christopher Moore and Hambolu Oluseyi, Dept. of PHES, Jacksonville State University, Jacksonville, AL 36265.

Alkenes are known to undergo addition reactions at lower temperatures and/or isomerization at higher temperatures. Maleic acid (cis-2-butene-l, 4-dioic acid), and its corresponding methyl ester (DMME) in which the alkene double bond is in conjugation with carboxyl group, is known to undergo isomerization on treatment with aqueous bromine or Br2/CC14 under UV light to form the thermodynamically more stable trans isomer. However, there are limited reports on the possible formation of any addition products under conditions of this study. Interesting results were observed in our studies with an attempt to standardize the conditions to achieve a more selective addition product. Dimethyl maleate (DMME), on treatment with slight excess of bromine using bromoform as catalyst and solvent gave selectively the addition product at low or high temperature conditions. However, replacement of bromoform by CC14 for solvent had a different effect. Several reactions were carried out, varying the solvent concentration and temperature to optimize the reaction conditions. Using bromoform as a catalyst, adding reagent bromine to substrate in 1:1 ratio and CC14 as solvent with 0.05 M concentration, under reflux conditions, we were able to achieve 95% yield of the addition product selectively. The results of various reactions are compared, products are characterized by IR and NMR and the reaction mechanism and stereochemistry are discussed.