Department of Chemistry

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Start date: 2004End date: 2009

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Now showing 1 - 7 of 7
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    Studies on adsorption of Ethyl Acetate Vapor in molecular sieves.
    (BITS, Pilani, 2004) Manjare, Sampatrao Dagu
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    Novel Applications of Conceptual Density Functional Theory Based Descriptors in Explaining Chemical Reactivity of Organic Reactions
    (BITS Pilani, 2008) Bagaria, Priyanka
    The thesis deals with novel applications of conceptual density functional theory (DFT) based reactivity descriptors to yield detailed information about chemical reaction s thermodynamics, kinetics, and mechanism. In particular, an altogether new approach has been adopted in this thesis to describe chemical reactions for a given substrate with another reactant under different conditions (in gas-phase and in solvent), formation of major and minor products, reaction mechanism including interpretation of rate-determining step, enhancement of rate and yield using these descriptors at qualitative level. Essentially, we have demonstrated how the correlation between experimental data and these reactivity descriptors can explain the kinetic aspects and the mechanism of chemical reactions. We have further generalized the adopted approach to particular type of reactions for which it is applicable. The reactivity descriptor developed by Parr et al. known as global electrophilicity index, has been considered mainly in the present thesis along with the other global and local reactivity descriptors since the majority of the reactions can be analyzed through the concept of electrophilicity/nucleophilicity of various species involved. newline In chapter 1, the brief review of literature, objectives and motivation for the present thesis are given. An overview on the theoretical developments of the conceptual density functional theory (DFT) based global and local chemical reactivity and selectivity descriptors (such as, electronegativity, chemical potential, hardness, softness, Fukui function, electrophilicity index, etc.) and the related electronic structure principles (i.e., electronegativity equalization principle, hard-soft acid-base principle, maximum hardness principle) have been presented.
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    Novel Applications of Some Hypervalent Iodine Reagents in Organic Transformations
    (BITS Pilani, 2009) Swapna Sundaree, M
    The thesis explores the novel applications of commonly used hypervalent iodine(III) newlinereagents in the synthesis of some key Intermediates and heterocyclic compounds ranging newlinefrom classical five-membered rings to small indole containing natural products. newlineThe first chapter briefly summarizes the development of hypervalent iodine chemistry newlinealong with their general aspects of bonding, structure, chemical properties and synthetic newlineapplications. newlineThe second chapter describes the utility of benign [hydroxy(tosyloxy)iodo]benzene newlinereagent (HTIB) in the solvent-free synthesis of and#945;-azidoketones in the presence of newlinetetrabutyl ammonium bromide (TBAB). newlineThe third chapter comprises of two parts: Part A deals with a one-pot solvent-free newlinesynthesis of and#946;-keto sulfones from enolizable ketones using [hydroxy(tosyloxy)iodo]benzene. newlinePart B describes the solvent-free synthesis of novel and#945;-tosyloxy-and#946;-keto sulfones from newlinecorresponding and#946;-keto sulfones using HTIB at room temperature. newlineIn the fourth chapter, Part A focuses on HTIB-mediated simple and efficient synthesis of newlinenaturally occurring 5-(3and#8242;-indolyl)azoles. Formation of 3-tosyloxyacetyl-1-benzenesulfonylindole newlineutilizing HTIB and cyclodehydration of and#945;-acylaminoketone in the presence newlineof p-toluenesulfonic acid, are the key-steps of this novel synthesis. The present work newlinehighlights the formation of hitherto unknown 3-tosyloxyacetyl-1-benzenesulfonylindole newlineby the reaction of 3-acetyl-1-benzenesulfonylindole with HTIB. The intermediate newlineand#945;-acylaminoketone was also utilized in the synthesis of 5-(3and#8242;-indolyl)thiazoles and newline5-(3and#8242;-indolyl)imidazoles, known as bioisosteres of naturally occurring newline5-(3and#8242;-indolyl)oxazoles. Part B of this chapter discusses the direct synthesis of newline5-(3and#8242;-indolyl)oxazoles from 3-acetyl-1-benzenesulfonylindole using appropriate nitrile in newlinethe presence of [hydroxy(2,4-dinitrobenzenesulfonyloxy)iodo]benzene (HDNIB). newlineIn the fifth chapter, synthesis and anticancer activity of novel 5-(3and#8242;-indolyl)-2-substituted- newline1,3,4-oxadiazoles, bioisosteres of naturally occurring 5-(3and#8242;-indolyl)oxazole