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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.
51

Studies on preparation of aromatic amines and their synthetic and biological applications /

Wang, Xuan. January 2005 (has links)
Thesis (Ph.D.)--Hong Kong University of Science and Technology, 2005. / Includes bibliographical references (leaves 252-274). Also available in electronic version.
52

The nucleic acid adducts of the hepatocarcinogenic aromatic amines and amides related to N-methyl-4-aminoazobenzene and N-hydroxy-2-acetylaminofluorene

Tarpley, W. Gary. January 1982 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1982. / Typescript. Vita. Description based on print version record. Includes bibliographical references.
53

The chemistry of dibenzo(a, e)cyclodeca-1,5-diene-3,8-diyne-7,10-diol

Reed, Jack Kellogg, January 1968 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1968. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
54

Surface properties of binary mixtures of benzene, toluene, and ethylbenzene with decane at the air-liquid and water-liquid interfaces

Gumkowski, Michael Jon. January 1983 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1983. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 103-108).
55

The chemistry of bicyclo(2,2,2)-2,5,7-octatriene (barrelene)

Grunewald, Gary L. January 1966 (has links)
Thesis (Ph. D.)--University of Wisconsin, 1966. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographies.
56

Sorption of synthetic aromatic anions onto polymeric ion exchangers : genesis of selectivity and effects of equilibrium process variables on sorption kinetics /

Li, Bing, January 1999 (has links)
Thesis (Ph. D.)--Lehigh University, 2000. / Includes vita. Includes bibliographical references (leaves 205-221).
57

Some reactions of methyl octadecenoates and related compounds

Perera, Buvipali Srima January 1972 (has links)
Part I: The Methyl trans-Methyleneoctadecanoates. The sixteen isomeric methyl trans-methyleneoctadecanoates have been synthesised from the corresponding methyl trans alkenoates by the Simmons-Smith reaction, and some of their physical properties examined. Only one isomer (methyl trans-9,10-methyleneoctadecanoates) has previously been reported. The gas liquid chromatographic data are interesting in that on both polar and non-polar columns the cis and trans isomers are well separated. The methyl trans-methyleneoctadecanoates show diagnostic nuclear magnetic resonance signals around 9.8 to 9.6r. The 2,3-; 3,4-; 5,6-; 16,17-; and 17,18- isomers differ from one another, but the remainder are very similar to each other. The mass spectra of some of the isomers were examined but they do not provide much useful information. Our data, along with that previously reported for the corresponding cis isomers (see ref 21), should assist in the recognition of these compounds. For complete identification, however it may be necessary, in addition to examine the mass spectrum of the hydrogenated ester. Part II: Halogenation of Unsaturated Long-chain Hydroxy Compounds. Neighbouring group participation in unsaturated hydroxy compounds occurring during reaction at the unsaturated centre has already been observed in appropriate long-chain compounds during various oxidation reactions and during oxymercuration. The halogenation of certain hydroxyalkenoates, octadecenols and octadecenoic acids has now been examined with a view to finding out if neighbouring group participation occurs during these reactions. The halogenating agents employed were iodine monochloride, bromine and chlorine giving rise to the electrophilic reagents I+, Br+ and C1+ respectively. In most reactions only the simple addition products (vic-dihalides) were observed and these were converted into ene-halides by dehydro- halogenation since the latter have been reported previously in only a few cases. The hydroxyl group was involved in halogenation in only a few instances - mainly in iodochlorination - to give substituted tetrahydrofurans (1,4-epoxides). Lactones were obtained during the halogenation of some unsaturated acids. Attempts to obtain N-heterocyclic compounds by the reaction of long-chain amines were less successful but the conversion of methyl ricinoleate to methyl 12-amino-oleate was satisfactorily achieved.
58

Excited state reactions of some aromatic carbonyl compounds

Ireland, John Frame January 1972 (has links)
The pK values for xanthone protonation in the S0, S1 and T1 states have been determined by direct measurement and by Forster Cycle calculation. Both methods for determining pK give the order for xanthone of pK(T1) > pK(S1) > pK(S0). A study of benzophenones and acetophenones showed this pK order to be a common one for aromatic carbonyl compounds. The pK order for these compounds has been explained in terms of the type of transitions involved and the S1-T1 splitting of these transitions. In the case of substituted aromatic carbonyl compounds the pK order reflects the effect of substitution on the lowest S0-S1 and transitions. Results are also presented on the effect of inorganic anions solvenli and temperature on xanthone fluorescence. Spectral details are reported for several xanthones, benzophenones, acetophenones, and anthraquinones.
59

Internal rotation about C-C and C-N bonds

Hamlin, Sally-Anne January 1978 (has links)
A study of the historical and more recent work on rotation about carbon-carbon and carbon-nitrogen bonds was the basis for the further investigation of three series of compounds: 1. 2,2'-disubstituted biphenyls, 2. N-benzyl-N-tosyl substituted anilines, 3. substituted quinone-anils. From this work it was established that, in certain compounds, the free energy (ΔG*) for hindered rotation cannot be discussed solely in steric terms but that electronic influences should also be considered. In. the substituted aniline series, it was concluded that a Hammett type correlation existed between the electronegativity of the substituents para to the amino group and the value of ΔG*. This correlation was extrapolated to explain the electronic influence of the substituents ortho to the amino group. Consideration was paid to the possibility that, for the ortho substituents, steric factors may outweigh electronic factors. An attempt was made to extend this correlation to explain the electronic influence of 2'- and 4'-substituents upon the ΔG* values and rates of racemization of-substituted biphenyls. However, it was found that the simple Hammett correlation was not followed and that, for the racemization studies, the entropy of activation (ΔS*) became a significant factor. The values of ΔG* for hindered rotation were obtained from the analysis of 100MHz n.m.r. spectra. The validity of these ΔG* values was discussed with respect to their accuracy and with respect to the effect of entropy. The synthetic routes used to obtain the three series of compounds were also discussed. The discussion of the synthetic routes includes the attempted preparations of a number of quinone-anils via the condensation of 2,6-di-t-butyl-l,4-benzoquinone with 4-substituted 2-benaylanilines. This was complicated by the production of impure samples of 2-benzylaniline and 2-benayl-4-chloroaniline. The synthesis of 2-benzyl-4-nitroaniline was not reproducible. The condensation reaction resulted in a number of products. These were separated by crystallization techniques and identified by high pressure liquid chromatography, I.R. spectroscopy, -13C and proton n.m.r. The structure of a new compound based on a dihydroindole containing one spiro carbon joined to a substituted quinone ring is proposed.
60

Reactive intermediates in the reactions of aryl halides with bases

Hall, Julia Kathleen Aylmer January 1969 (has links)
The reaction of a series of 2,6-dimethylaryl halides with strong base has been investigated. Debromination to give polymethylbenzenes has been found to occur in all the systems studied and varying amounts of higher-boiling products, mainly polymethyl-bibenzyls, have also been obtained. Various mechanisms for these new reactions are discussed and the participation of an unusual triplet carbene intermediate is suggested. The related thermal decomposition of sodium o-halophenates has also been investigated. The participation of a similar carbene intermediate in this reaction appears to be unlikely. Possible mechanisms for the formation of diphenylmethanes obtained in the decomposition of sodium pentachlorophenate in methylbenzenes, are discussed.

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