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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
141

Synthesis of o-isotoluenes, o-quinodimethanes, and benzoenynyl carbodiimides and their cyclizations to polycyclic and heterocyclic compounds

Zhang, Quan, January 1999 (has links)
Thesis (Ph. D.)--West Virginia University, 1999. / Title from document title page. Document formatted into pages; contains xvi, 108 p. : ill. Includes abstract. Includes bibliographical references (p. 98-108).
142

The isotopological homodesmotic reaction a further refinement to the quantification of aromaticity /

Olguin, Marco Augusto, January 2009 (has links)
Thesis (M.S.)--University of Texas at El Paso, 2009. / Title from title screen. Vita. CD-ROM. Includes bibliographical references. Also available online.
143

The chemistry of nickel on the edge of polycyclic aromatic hydrocarbons /

Brown, James S., January 2004 (has links)
Thesis (M.S.)--University of Missouri-Columbia, 2004. / Typescript. Includes bibliographical references (leaves 58-63). Also available on the Internet.
144

Investigation of the chemoselectivity and efficiency of the benzannulation reaction of electron poor aryl Fischer carbene complexes : synthetic studies toward (+)-olivn /

Liptak, Vincent Paul. January 2000 (has links)
Thesis (Ph. D.)--University of Chicago, Dept. of Chemistry, August 2000. / Includes bibliographical references. Also available on the Internet.
145

The anaerobic, phototrophic metabolism of 3-chlorobenzoate by Rhodopseudomonas Palustris.

Kamal, Varsha Subhash, Carleton University. Dissertation. Biology. January 1992 (has links)
Thesis (Ph. D.)--Carleton University, 1993. / Also available in electronic format on the Internet.
146

Synthesis of novel polycyclic aromatic compounds via cascade cyclizations of benzannulated enyne-allenes

Zhang, Yanzhong, January 1900 (has links)
Thesis (Ph. D.)--West Virginia University, 2005. / Title from document title page. Document formatted into pages; contains x, 165 p. : ill. Includes abstract. Includes bibliographical references (p. 65-71).
147

The chemistry of nickel on the edge of polycyclic aromatic hydrocarbons

Brown, James S., January 2004 (has links)
Thesis (M.S.)--University of Missouri-Columbia, 2004. / Typescript. Includes bibliographical references (leaves 58-63). Also available on the Internet.
148

The NMR properties, photochromism and efficient syntheses of several [e]-annelated dimethyldihydropyrenes

Ward, Timothy Robbins 07 August 2018 (has links)
A systematic and efficient route to [e]-annelated derivatives of 2,7-di-t- butyl-trans-10b, 10c-dimethyl-10b,10c-dihydropyrene 34 has been achieved which provides access to the benzo, naphtho, and anthro derivatives of 34, by means of a Diels - Alder reaction of an aryne with a furan. Reaction of the annulyne derived from bromide 50 with furan gave adduct 52 which could be both deoxygenated to benzo derivative 53 and reacted with tetrazine 54 to yield the annuleno furan 55 which subsequently with benzyne and 2,3-naphthalyne yielded adducts which were deoxygenated to naphtho and anthro derivatives 57 and 59. Reaction of the furan 55 with the benzoannulyne derived from 65 gave the cyclophane fused pyrene 68, while reaction of the annulyne derived from 50 with the bisfuran 62 gave the chrysene bis pyrene 60. These fused dihydropyrene derivatives are all photochromic, and the photoisomerizations were studied In each case. Dihydropyrenes 53, 57, 59, and 65 are simple photoswitches, while 60 and 68 are more complex multiple state switches. In each case the kinetics of the MOD to DMDHP reaction was followed to obtain the activation energy, enthalpy, and entropy. It was found that the activation enthalpies and energies decreased through the series, from the benzo to the naphtho to the anthro system. This suggested that the transition states for the MCD to DMDHP reactions were stabilized by resonance with the respective annelated fragments. Detailed analysis of the NMR data of all compounds yielded an experimental aromaticity scale in which δ(Me) or δ(H4) could yield information to obtain the relative resonance energy of the annelating fragment. Correlations between methyl and H4 protons were obtained and compared to related systems. / Graduate
149

Formation and reactions of ipso adducts from chlorination of 2-methyl-2-aryloxypropanoic acids

Ji, Ruizhi 20 June 2018 (has links)
Chlorination of 2-methyl-2-aryloxypropanoic acids with aqueous hypochlorous acid gives spiro chloro adducts in moderate to high yields. In chlorination of 2-methyl-2-(2-methylphenoxy)propanoic acids, 1,2-adducts are formed, while in the case of 2-methyl-2-(4-methylphenoxy)propanoic acids, 1,4-adducts are obtained. In addition to the spiro adducts, 2-methyl-2-(4-chlorophenoxy)propanoic acids in the former case, and 2-methyl-2-(2-chlorophenoxy)propanoic acids in the latter case are formed, respectively. No 6-chlorosubstituted products are detected on chlorination of any of the substrates. Chlorination of 2-methyl-2-(2,4-dimethylphenoxy)propanoic acid affords only the 1,4-adduct. However, chlorination of 2-methyl-2-(5-chloro-2,4-dimethylphenoxy)propanoic acid gives both the 1,2- and the 1,4-adduct. 2-Methyl-2-(3,5-di-t-butylphenoxyl)propanoic acid on chlorination yields the diastereomeric secondary chloro adduct, 8-chloro-7,9-di-t-butyl-3,3-dimethyl-1,4-dioxaspiro (4,5) deca-6,9-dien-2-one. Under neutral and non-polar conditions, most of the 1,2-adducts undergo a thermal rearrangement of the chlorine which is shown to be a (1,5) sigmatropic chlorine shift. The rearrangement rates are highly dependent on the nature of the substituents in the diene systems. Under acidic and non-nucleophilic conditions, most of the 1,4-adducts undergo an intramolecular 1,2 chlorine shift followed by aromatization to give the 3-chloro-substituted products. For the dienes in which the 3-position is originally substituted, successive 1,2 chlorine migrations and/or side chain substitution are observed. On the other hand, the 1,2-adducts under similar reaction conditions undergo an intermolecular 1,4 chlorine shift to give the 5-chlorosubstituted products. In the case that the 5-position is substituted by a methyl group, side chain substitution at the 5-methyl takes place. In the presence of added base, solvolyses of the 1,4-adducts in methanol affords simple solvolysis products and/or 1,2 carboxyl rearranged products. The kinetic studies of the solvolyses of the 1,4-adducts have been carried out. The results reveal the substituent effects on both the simple solvolysis displacement and the rearrangement reactions. / Graduate
150

The chemistry of flavins and related systems

Higgins, Raymond January 1965 (has links)
No description available.

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