A polymer photodetector is fabricated using polythiophene with chiral alkyl side chains. The Cotton effect is observed in the CD spectrum of the photodetector, indicating an unequal absorbance of left- and right-handed circular polarized light (CPL). The photodetector is proven to be able to identify incident left- and right-handed CPL. Polymer photodetectors that are made from R- and S-limonene induced achiral polymers are fabricated. A “hot spin-coating” process is introduced to cast uniform limonene induced polymer films. As a result of chirality transfer, Cotton effects are also observed in these photodetectors’ CD spectra. A model is suggested to explain the chirality generation of the polythiophene with chiral alkyl side chains and limonene induced achiral polymers. / Thesis (Master, Chemistry) -- Queen's University, 2014-03-25 14:37:23.168

En el curso de esta Tesis Doctoral, se sintetizaron librerías de (1,2)-diaminas enantiopuras y 2,2’-bifenoles pro-quirales. La transferencia de quiralidad desde la diamina al bifenol, mediante puentes de hidrógeno o coordinación a un metal (ZnII, CuII), fue demostrada por dicroísmo circular (DC). El comportamiento en disolución de los complejos supramoleculares (usando puentes de hidrógeno), así como sus constantes de asociación, fue estudiado mediante valoraciones de RMN, UV-vis y ITC. La determinación de las configuraciones absolutas de los complejos de ZnII se consiguió mediante la resolución de las estructuras de rayos-X y los estudios de DC, tanto a un nivel teórico como experimental. Un nuevo ligando fosforado, potencialmente catalítico, fue preparado a partir de 2,2’-bifenol, mostrando el camino para el desarrollo de nuevos catalizadores supramoleculares. / During the course of the thesis libraries of chiral (1,2)-diamines and prochiral 2,2’-biphenol derivatives were synthesised. The transfer of chirality from the diamine to the biphenol moiety mediated either by hydrogen bonding or coordination to a metal centre (ZnII, CuII) was demonstrated by CD (circular dicroism). The behaviour in solution of the hydrogen bonded complexes was investigated by NMR spectroscopy, UV-vis and ITC titrations (determination of association constants. The determination of absolute configurations of the ZnII complexes was achieved by X-ray structure determination and CD analyses both on the experimental and theoretical level. Last but not least, a new potentially catalytic phosphane ligand was derived from a dynamically racemic 2,2’-biphenol derivative.

Une approche hors ‘pool chiral' du système tricyclique 8b-azaacenaphthylène de l'alcaloïde (-)-205B a été développé. Cet alcaloïde, caractérisé par son squelette tricyclique rarement rencontré dans les produits naturels, a suscité un intérêt scientifique important ces dernières années du à son activité biologique potentiel vis à vis de maladies neurodégénératives. Cependant, due à sa très faible bio-disponsibilitié son mode d'action détaillée est actuellement inconnue. Notre stratégie se caractérise par plusieurs transformations remarquables. Une cycloaddition thermique [2 + 2] hautement stéréosélective et une expansion de cycle via un réarrangement de Beckmann donnent accès à un lactame fonctionnalisé. Une réaction de Mannich vinylogue fournit efficacement un buténolide qui est ensuite rapidement transformé en un motif indolizidinone. Après méthylation de cet intermediaire bicyclique, une réaction de cyclisation de type aza-Prins, rarement utilisée en synthèse, conduit à un intermédiaire avancé possédant le système tricyclique qui caractérise le produit naturel. Ainsi, cette approche défini une base solide pour une nouvelle voie d'accès à cet important et particulièrement rare alcaloïde isolé à partir de peau de grenouille néotropicales Dendrobates pumilio considerée comme espèce protégée. / A non-chiral pool approach to the 8b-azaacenaphthylene ring system of the frog poison alkaloid (-)-205B has been developed. This rare tricyclic alkaloid has been of considerable synthetic interest in recent years owing to its potential biological activity against neuronal disorders. However, due to lack of material, a detailed study of the mode of action of this natural product has not yet been reported. Our strategy features several noteworthy transformations. A highly diastereoselective thermal [2+2] cycloaddition and a ring expansion through Beckmann rearrangement generates the functionalised lactam intermediate. An efficient vinylogous Mannich reaction then provides access to a butenolide, which subsequently leads to an indolizidinone ring system. After installation of a methyl group on this bicyclic intermediate, a relatively unexplored aza-Prins cyclization has been successfully employed to obtain an advanced intermediate, possessing the desired tricyclic system found in the natural product. This approach has laid a solid foundation for a novel access to this potentially important but scarce alkaloid extracted from a neotropical frog Dendrobatus pumilio that is threatened to be endangered.

No description available.

Owing to the growing demand for enantiopurity in biological and chemical processes, tremendous efforts have been devoted to the synthesis of homochiral metal-organic materials (MOMs) because of their potential applications in chiral separation and asymmetric catalysis. In this dissertation, the synthetic strategies for homochiral MOMs are discussed keeping the focus on their applications. Two distinct approaches have been taken to synthesize chiral structures with different topologies and accessible cavities. The chiral MOMs have been utilized in enantioselective separation of racemates. Chiral variants of the prototypal metal-organic framework MOF-5, δ-CMOF-5 and [lambda]-CMOF-5, have been synthesized by preparing MOF-5 in the presence of L-proline or D-proline, respectively. CMOF-5 crystallizes in chiral space group P213 instead of Fm-3m as exhibited by MOF-5. The phase purity of CMOF-5 was validated by single crystal and powder X-ray diffraction, IR spectroscopy, TGA, N2 adsorption, microanalysis and solid-state CD. CMOF-5 undergoes a reversible single crystal to single crystal phase change to MOF-5 when immersed in a variety of organic solvents although N-methyl-2-pyrolidone, NMP, does not induce loss of chirality. Indeed, MOF-5 undergoes chiral induction when immersed in NMP, affording racemic CMOF-5. A pair of homochiral network materials (CNMs), [Co2(S-man)2(bpy)3](NO3)2·guests (1S) and [Co2(R-man)2(bpy)3](NO3)2·guests (1R) based upon S-mendelic acid and R-mendelic acid were synthesized and characterized, respectively. The cationic networks contain 1D homochiral channels with the cross section of 8.0 Å × 8.0 Å. The chiral amphiphilic channel surfaces lined with hydrophilic nitrate anions and hydrophobic phenyl groups are capable for multiple interactions with guest species. Chiral resolution of 1-phenyl-1-propanol (PP) enantiomers was performed utilizing the homochiral porosity of 1S and 1R through different time period at different temperatures with/without additives. The mechanism for enantioselective separation of PP was fully investigated through single crystal structural analysis of guest exchanged 1S and 1R. Chiral resolution of PP revealed enhanced performance with additive, which can significantly improve the ee value from 32% to 60%.

No description available.

No description available.

No description available.

No description available.