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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.
11

Investigations on the synthesis of new photochromic oxazine derivatives

Pritchard, Martin David January 2000 (has links)
Initial studies were based on previous work at Edinburgh in which the reaction of the lithium salt of 1,2-naphthalenedione 1-oxime with 2-bromo-2,2-diphenylacetaldehyde was found to afford an oxime ether which was reduced with triphenylphosphine to afford 3,3-diphenyl-3<i>H</i>-naphth[2,1-<i>b</i>]-1, 4-oxazine. Similarly, 2,2-diphenyl-2<i>H</i>-naphth[1,2-<i>b</i>]-1,4-oxazine was prepared in a parallel synthetic strategy using 1,2-naphthalenedione 2-oxime as key starting material. To facilitate the expansion of this strategy, further bromo-aldehydes functionalised with variously substituted aromatic moieties were prepared. Reaction of these bromo-aldehydes with 1,2-naphthalenedione 1-oxime lithium salt, followed by reduction of the resulting oxime ethers, facilitated the synthesis of a number of novel 3,3-diaryl-3<i>H</i>-naphth[2,1-<i>b</i>]-1,4-oxazine derivatives. On encountering problems in the synthesis of certain diaryl bromo-aldehydes, the synthesis of alternative diarylacetaldehyde derivatives amenable to reaction with naphthalenedione oxime lithium salts was previously inaccessible halogeno-aldehydes was investigated. Using 1,2-naphthalenedione 2-oxime and 9, 10-phenanthrenedione 9-oxime as starting materials the aforementioned methodologies were applied to the respective syntheses of 2,2-diaryl-2<i>H -</i>naphth[1,2-<i>b</i>]-1,4-oxazines and 2,2-diaryl-2<i>H</i>-phenanthro[9,10-<i>b</i>]-1,4-oxazines. Investigations were also made into the mechanism of the formation of these novel photochromic species. The chemistry of certain novel naphth-1, 4-oxazines and phenanthro-1, 4-oxazines was investigated and they were found to behave as cyclic imines. Photochromic 3,3-diaryl-3<i>H</i>-pyrido[3,2-<i>f</i>]-1, 4-benzoxazines were also prepared. However, the attempted synthesis of 2,2-diphenyl-2<i>H</i>-acenaphtho[1,2-<i>b</i>]-1, 4-oxazine was unsuccessful. Work was also undertaken on various synthetic routes to diarylnaphth-1, 3-oxazine derivatives. Initial attempts were based on the preparation and cyclisation of 1-benzoylaminomethyl-2-naphthol. This having failed, an alternative approach involving the reaction of diarylketimines with 2-hydroxy-1-naphthaledhyde was investigated and successfully afforded 3,3-diaryl-3<i>H</i>-naphth[1,2-<i>e</i>]-1, 3-oxazines. In parallel with these studies the analogous syntheses of 2,2-diphenyl-2<i>H</i>-naphth[2,1-<i>e</i>]-1, 3-oxazine and 2,2-diaryl-2<i>H</i>-phenanthro[9,10-<i>e</i>]-1, 3-oxazines were also achieved.
12

Photochemical reactions of acetylene and hydrogen sulphide

Morton, John January 1966 (has links)
No description available.
13

Elementary Computing with Luminescent Molecules

West, M. E. S. January 2011 (has links)
No description available.
14

Applications of Low-Level Beta Emitters to Radiocarbon Dating and to Kinetic Studies on Reissert Compounds

Lowe, S. P. January 1977 (has links)
No description available.
15

The effect of electrolytes upon the light absorption of aromatic compounds

Rogers, A. R. January 1963 (has links)
No description available.
16

Pulse length dependence of optical damage in ADP and KD*P

Scott, J. C. January 1978 (has links)
No description available.
17

Radiochemical studies of the oxidation of natural rubber

Houseman, Terence Henry January 1970 (has links)
No description available.
18

Routes towards photochemically initiated gas release in polymeric systems

Davies, Paul R. January 1995 (has links)
No description available.
19

Photophysics and fluorescence imaging of dye sensitisers

Petrasek, Zdenek January 2000 (has links)
No description available.
20

Heterogeneous photocatalytic degradation studies of organic compounds in water

Ngwang, Helen Chonde January 1996 (has links)
No description available.

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