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Physical Sciences and Mathematics Commons

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Theses/Dissertations

Chemistry

Synthesis

University of Missouri, St. Louis

Publication Year

Articles 1 - 3 of 3

Full-Text Articles in Physical Sciences and Mathematics

The Synthesis And Characterization Of Photoluminescent Conjugated Frameworks Containing Silicon And Germanium, Douglas William Hammerstroem Dec 2016

The Synthesis And Characterization Of Photoluminescent Conjugated Frameworks Containing Silicon And Germanium, Douglas William Hammerstroem

Dissertations

Siloles and 9-heterofluorenes (Si, Ge) are conjugated π-electron systems containing Group 14 atoms which demonstrate unique properties such as high electron affinity, mobility, and bathochromically shifted optical spectra relative to their all-carbon analogs. This is due to their low-lying lowest-unoccupied molecular orbital (LUMO) which is resultant of the σ*-π* conjugation between the exocyclic groups at the Group 14 center and the butadiene unit of the ring. As a consequence, they have received considerable attention for their use as components for a wide variety of optical and electronic applications such as organic light emitting diodes (OLEDs), photovoltaic devices, field-effect transistors (FETs), …


Templated Oligosaccharide Synthesis, Jia Guang Xiao Aug 2016

Templated Oligosaccharide Synthesis, Jia Guang Xiao

Dissertations

Glycosyl transfer within the active site of an enzyme involves the arrangement of the gly-cosyl donor and glycosyl acceptor in close proximity to each other. To mimic this pro-cess, intramolecular glycosylations are carried out where the donor and acceptor are linked together via a spacer. Correct orientation, rigidity and position of the spacer play a vital role in the selectivity and yield of reactions in this “molecular clamp method”. Though current methodologies show promising results in terms of yield and selectivity, the need to synthesize different complexes to ensure selectivities in all types of glycosidic linkages is a large deterrent …


Siloles Bearing Coordination-Active 2,5-Substituents: Synthesis, Reactivity, Structural And Spectral Properties., James Bryan Carroll Aug 2013

Siloles Bearing Coordination-Active 2,5-Substituents: Synthesis, Reactivity, Structural And Spectral Properties., James Bryan Carroll

Dissertations

Siloles, or silacyclopentadienes and other group 14 metalloles are structurally analogous to their all-carbon analogue, cyclopentadiene, except for the heavy group 14 element (i.e., Si, Ge, Sn, and Pb) in the 1-position. The placement of the heavy element in this position allows for unique properties, such as high electron affinity, mobility, and bathochromically shifted optical spectra, as compared to cyclopentadienes, and the relatively low-lying lowest-unoccupied molecular orbital (LUMO) helps to account for these properties. The substituents about the silole have a significant impact on the electronics and properties observed, with 2,5-substituents inducing the most substantive changes. Even as many 2,5-substituents …