<p> Chiral 1-arylprop-2-en-1-ols and 1-arylprop-2-yn-1-ols are useful building blocks for modern pharmaceuticals. Previous work has found that enzyme catalysis is a potential new enantioselective synthetic route to the former. We found that <i>Candida antarctica</i> lipase is also an effective catalyst for kinetic resolution of various substituted 1 arylpropargylic acetates and haloacetates, affording the respective (<i>R</i>) -1 arylproargylic alcohols with high enantioselectivity (99-100% <i>ee</i>). By varying the substituents on both sides of the ester bond, we discovered that the deacylation of lipase is likely the rate-determining step for our catalytic system. A greater challenge is designing a dynamic kinetic resolution (DKR) system for such substrates, which combines a resolving catalyst (lipase) with a racemizing catalyst, and can potentially lead to quantitative conversion of a racemic substrate into an enantiopure product. We studied the efficacy of various transition-metal complexes for substrate racemization and will report our results for In and Cu compounds. </p><p> While kinetic resolution has been performed on the 1-arylallylic acetates with excellent yield and enantioselectivity and the DKR regime has been designed, the resulting site-isolation system has required further testing and fine tuning. We have herein investigated the utilization of macroscale site-isolation as well as various factors including solvent, and acyl donor effects in order to optimize conditions of the system.</p>

<p> The epoxide-olefin [3+2] cycloaddition reaction is an important tool in synthesizing heterocyclic five member rings. Such cyclic compounds are well known for the formation of biologically active compounds. In this experiment, we developed a method for a [3+2] cycloaddition reaction between gem-dicyano phenyl epoxide and diethyl (E)-2-fluoromaleate to synthesize 2, 2-dicyano-3, 4-diethoxycarbonyl-4-fluoro-5-phenylfuran. The yield of the product was 55.56 %. </p><p> Fluorine is small in size and is the most electronegative element. These properties of fluorine make its incorporation into drugs easy and also increase the efficacy and selectivity of the drugs. Atropic acid has wide applications as an antagonist. The non-fluorinated atropic acid derivative binds to glycine binding sites, which help in the treatment of a number of disease states. Moreover, its derivatives are used in the preservation of beverages, pests control agents and fungicides. Considering the above facts, fluorination of ethyl atropate using XeF₂ via an electrophilic addition reaction in the presence of compounds like I₂, Se₂Ph₂ and S2Ph₂ was performed. The percentage yield of addition products were fairly high, ranging from 63 % to 67 %.</p>

Dicycloproparenes 1 and 2 were synthesized by treating the Diels-Alder adducts of 1-bromo-2-chlorocyclopropene and either 2,3,5,6-tetramethylidene-bicyclo[2.2.2]octane (3) or 1,2,4,5-tetramethylenecyclohexane (4) with potassium t-butoxide in tetrahydrofuran.* The silver catalyzed polymerization of each dicycloproparene was investigated. The dimers 5a and 5b were observed and isolated at an early stage during the polymerization of dicycloproparene 1.* The ladder polymer formed by treating the linearly fused dicyclopropanthracene 2 with silver ion in chloroform was characterized by solid state nuclear magnetic resonance spectroscopy. The insoluble dimer of 2 could not be isolated.* *Please refer to dissertation for diagrams.

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The structure of the yellow form of arsenomethane has been studied by single crystal x-ray techniques at reduced temperature. The crystals are monoclinic and belong to the space group C2h5 - P21/n, with a = 8.88 A, b = 12.55 A, c = 11.61 A, and beta = 101&deg;46'. The unit cell contains four molecules. Harker synthesis, Patterson section and Fourier projection methods were used to locate the arsenic atoms. Geometrical considerations were combined with the difference Fourier method to find the carbon atoms. The parameters were refined by application of the least-squares procedure to three dimensional diffraction data. The molecule consists of a puckered, five-membered ring of arsenic atoms to each of which is attached a methyl group. The As-As bond length varies significantly from 2.42 A to 2.45 A, and the C-As bond length varies from 1.94 A to 1.98 A. The As-As-As bond angle varies from 971/2&deg; to 1051/2&deg; and the C-As-As bond angle from 94&deg; to 1021/2&deg;.

Within the past dozen years skilled investigators in several laboratories have achieved considerable success in detecting distinct crystalline modifications of both pure and mixed sodium soaps. Some measure of the resulting clarification of knowledge pertaining to soap crystals is general acceptance of the Thiessen and Stauff alpha sodium stearate as a hemihydrate with monoclinic crystal symmetry established by Buerger and his coworkers. Unfortunately, however, such wide agreement does not extend over proposals for at least nine other crystalline phases said to exist at room temperature and atmospheric pressure. This present investigation had been undertaken with the hope not of solving the multitudinous problems pertaining to soap structures, but more simply of demonstrating the possibilities for applying refined techniques of water vapor sorption and desorption in conjunction with x-ray diffraction measurements to these problems.

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