Thesis - Open Access
Master of Science (MS)
As analyzed by mass spectrometry, ultraviolet spectroscopy, and gas liquid chromatography, the unconjugated thiones prepared were composed of mainly monomer in the presence of some dimer. Certain literature reports on the ultraviolet absorption spectra of unconjugated thiones are erroneous. The monomeric thiones have two electronic transitions at 500nm and at 2J0nm. A transition observed at 210nm was assigned to the transition of the thione dimers (l,J-dithietanes). Nuclear magnetic resonance studies showed that the hydrogens cl to the thione chromophore resonate at lower field than do hydrogens of the corresponding ketones. The chemical shift of the methyl group next to the tbione chromophore was observed to be at 2.75owith respect to TMS in carbon tetrachloride. Mass spectral studies indicated that the thiones have fragmentation patterns similar to the corresponding ketones. Dimers (l,3-dithietanes) of monomeric thiones form via a photosynthetic pathway. The mechanism was suggested as occurring by an excited state.
Library of Congress Subject Headings
South Dakota State University Theses
Number of Pages
South Dakota State University
Nicols, Patrick, "Physical and Chemical Properties of Unconjugated Thiones" (1970). Electronic Theses and Dissertations. 3819.