| Summary: | Thesis (Ph.D.)--Memorial University of Newfoundland, 2010. Chemistry Includes bibliographical references (leaves 155-166) The projects outlined in this thesis were aimed at the synthesis and characterization of π-extended tetrathiafulvalene (TTF) derivatives, and exploration of their applications in materials chemistry. In these five projects, the synthetic targets have been successfully synthesized, and their electronic and electrochemical properties have been extensively explored and elucidated by CV, UV-Vis and fluorescence techniques. -- The donor-acceptor (D-A) systems containing anthraquinone-type TTF analogues in the first and fourth projects exhibited obvious electronic push-pull effect within the molecules. This property renders them potential candidates for intramolecular charge-transfer and nonlinear optical materials. In these two projects, a TTFAQ donor was attached to a series of D/A groups such as anthraquinone, t-butylthiophenyl, amino and carboxyl ester groups via two acetylene bridges. -- In the third project, thiophene was employed as π-spaces to spatially expand the conjugation paths between TTFs. It was expected that this could contribute many beneficial molecular properties, such as increased dimensionality, improved donor ability, intimate solid-state packing, minimized on-site Coulombic repulsion in the di- or polycationic states, and enhanced stability of the corresponding cation radical or dication species. -- The fourth chapter focused on developing effective saccharide sensors using a TTFAQ-boronic acid as a platform. The work has demonstrated that phenylboronic acid and TTFAQ moieties can be efficiently tethered together via the CuAAC (click) reaction and TTFAQ-diboronic acid was found to give different voltammetric responses to the four saccharides tested. -- The fifth and sixth chapters are concerned with TTF-based chemical sensors for metal cations. The signal transduction mechanism adopted in the fifth project is an internal charge-transfer mechanism (ICT), while a photoinduced electron-transfer mechanism (PET) in the system is described in the sixth chapter. The products in the fifth project displayed high sensitivity and selectivity for Cu²⁺ cation. The crown ether-annulated TTFAQ prepared in the sixth project showed decent sensitivity to Ag⁺, Mg²⁺, Li⁺ and Ba²⁺, and particularly high selectivity for Ba²⁺ ion.
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