Doctor of Philosophy / Department of Chemistry / Duy H. Hua / The discovery of new methodologies to advance the fields of synthetic organic, nanoclusters, and polymer chemistry is critical in the asymmetric synthesis of organic compounds. Particularly, catalytic asymmetric oxidation reactions are economic. The oxidation reactions provide chiral molecules and additional functionality onto the molecules for functional group manipulation. New kinds of polymers, namely chiral-substituted poly-N-vinylpyrrolidinones (CSPVPs), stabilize the bimetallic nanoclusters such as Pd/Au or Cu/Au and induce chirality. These chiral polymers wrap around the nanometer-sized (~3 nm) bimetallic nanoclusters and catalyze a number of enantioselective oxidation reactions using oxygen or hydrogen peroxide as the oxidant. Cycloalkanediols were asymmetrically oxidized by 1 atm of oxygen gas to yield the corresponding hydroxyl ketone under the catalysis of Pd/Au (3:1) – CSPVP nanoclusters. Alkenes were oxidized by Pd/Au (3:1)-CSPVP nanoclusters under 2 atmospheric of oxygen in water to give the syn-dihydroxylated products in high chemical and excellent optical yields. Various cycloalkanes underwent regio- and enantio-selective C-H oxidation with Cu/Au (3:1)-CSPVP and 30% hydrogen peroxide to produce the corresponding chiral oxo-molecules in very good to excellent chemical and optical yields. We further discovered an enantioselective desymmetrization of , -dialkenyl-alkanols and , -dialkenyl-amino acid ethyl esters to give chiral disubstituted lactones and lactams, respectively. A number of medium-sized natural products and drugs were also oxidized regioselectively to give the corresponding mono-oxygenated products. A broad-spectrum predictive C-H oxidation of complex molecules is possible. Chapter 1 mainly discussed the synthesis and characterization of the new classes of chiral substituted PVP and bimetallic nanoclusters. Chapter 2 focus on various kind of oxidation reactions by the catalysis of CSPVP stabilized bimetallic nanoclusters. Among various bioluminescence assays, firefly luciferase based bioluminescence assays are popular due to their high specific activity, low background noise and ease of use. However, it has been found that some aromatic carboxylic acid substantially inhibited the firefly luciferase reporter enzyme’s activity. In order to study firefly luciferase inhibition and the proteins associated with inhibition mechanism, we designed two 6-(dimethylamino)-2-phenylisoindolin-1-one derivatives as probe molecules. The synthesis of one probe molecule is discussed in Chapter 3 and the further investigation of its inhibitory activity on firefly luciferase is being conducted by our collaborate.

Doctor of Philosophy / Department of Physics / Talat S. Rahman / In this work we present a study of the geometric, electronic, vibrational and magnetic properties of several nanostructured systems for which experimental data call for a theoretical understanding. In order to investigate the effect of magnetic dipolar interactions on the magnetization of nanomagnets arranged in finite lattices, we utilize a phenomenological classical approach, which is based on the Landau-Lifshitz equation. Dipolar interactions lead to hysteretic behavior of the magnetization curves and established that the external field sweep rate, sample temperature, and shape anisotropy play a role in determining the specifics. Our results (derived from a classical approach) for magnets arranged in a square lattice suggest that stepped hysteresis curves do not have necessarily a quantum origin (quantum tunneling of the magnetization). We also find that in the square lattice small changes in the dipolar strength introduce sudden transitions in the magnetic hysteresis. For the examination of geometric vibrational and electronic structure of systems of interest, we turn to density functional theory (DFT), which is the leading technique for modeling nanoscale systems from first principles. We have applied DFT to either address some old queries of surface science, such as the dynamics of the CO-chemisorbed Cu(001) surface, or to contribute to the forefront of hydrogen-based economy through the comprehension of the growth and diffusion of Pt islets on Ru(0001), or to predict the geometric and electronic properties of materials to-be-created, as in the case of core-shell bimetallic nanoclusters. In the case of CO on Cu(001), although the bond has been considered to be weak enough so as to treat the adsorbate and substrate separately, our calculations are able to reproduce measurements and provide evidence that the dynamics of the molecule is influenced by the substrate and vice versa, as well as by intermolecular interactions. Taking into account the adsorbate-substrate interplay, has furthermore clarified issues that were pending for the clean surface and led to the correct interpretation of some features in the phonon dispersion of the chemisorbed surface. DFT has also directed us to the conclusion that the catalytic properties of few-atom Pt islets on Ru nanoclusters are preserved by the low probability of these islets to diffuse through the edges of the Ru nanoclusters. Moreover, the analysis of the Ag_{27}Cu_7 nanoalloy from ab initio methods has opened a wide panorama in terms of the geometry, coordination, energetics, and electronic structure of alloyed phases, in general,that may aid in the assembling on new materials.