dc.contributor.advisor |
Associate Professor P.S. Rutledge |
en |
dc.contributor.author |
Marsh, Nicholas Francis |
en |
dc.date.accessioned |
2007-11-14T22:19:05Z |
en |
dc.date.available |
2007-11-14T22:19:05Z |
en |
dc.date.issued |
1992 |
en |
dc.identifier.citation |
Thesis (PhD--Chemistry)--University of Auckland, 1992 |
en |
dc.identifier.uri |
http://hdl.handle.net/2292/2090 |
en |
dc.description |
Restricted Item. Print thesis available in the University of Auckland Library or may be available through Interlibrary Loan. |
en |
dc.description.abstract |
A new synthetic route to the half-ester (14), usually prepared from a Stobbé Condensation has been investigated. Both of the cis and trans paraconic esters, (25) and (26) respectively, can be ring-opened with sodium methoxide in methanol to give a good yield of the half-ester (14). This also provides further evidence for the intermediacy of paraconic esters in the Stobbé Condensation. A number of partially methylated compounds, (81), (82) and (85) have been isolated from the synthetic route leading to the dimethoxy aldehyde (55). The aldehyde (55) has been successfully employed in a Wittig reaction with the dimethoxy ylide (70), giving a 96% yield of the α,β-unsaturated ester (86). If left in solution, this alkene photoisomerises to a 1:1 mixture containing the E and Z esters, (86) and (87). Reduction of the E isomer (86) with 10% Pd/C, gives a product (93) of over-reduction. The desired product (96) was obtained when the catalyst was pre-hydrogenated and washed with a dilute base solution. The yield of the half-ester (59) has been improved to 85%. A two step reductive methylation of the quinone carbonyls has been used with moderate success to prepare (106) and (110). Asymmetric hydrogenation of the half-ester (14) was successful giving a 53.5% ee using a rhodium-DIOP catalyst. The dimethoxy ester (86) was less successful as a substrate giving a quantitative yield of the reduction product, but the absence of any optical activity. A Diels-Alder route has been linked to a synthetic route developed in this department involving sequential reductive Claisen rearrangements. A "one pot" route to the key intermediate (164) has been developed. A new preparation of 1,2-anthracenedione (192) in a 73% yield from alizarin is reported. A synthetic route to the aldehyde (194) from 1,2,5-trihydroxyanthraquinone (177) involving protection of 1,2-diphenols as benzophenone ketals is discussed. A number of unexpected products on this sequence are reported. |
en |
dc.language.iso |
en |
en |
dc.publisher |
ResearchSpace@Auckland |
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dc.relation.ispartof |
PhD Thesis - University of Auckland |
en |
dc.relation.isreferencedby |
UoA9947171914002091 |
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dc.rights |
Restricted Item. Print thesis available in the University of Auckland Library or may be available through Interlibrary Loan. |
en |
dc.rights.uri |
https://researchspace.auckland.ac.nz/docs/uoa-docs/rights.htm |
en |
dc.title |
Synthetic intermediates for anthracyclinones and lignans |
en |
dc.type |
Thesis |
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thesis.degree.discipline |
Chemistry |
en |
thesis.degree.grantor |
The University of Auckland |
en |
thesis.degree.level |
Doctoral |
en |
thesis.degree.name |
PhD |
en |
dc.subject.marsden |
Fields of Research::250000 Chemical Sciences |
en |
dc.rights.holder |
Copyright: The author |
en |
dc.rights.accessrights |
http://purl.org/eprint/accessRights/ClosedAccess |
en |
dc.identifier.wikidata |
Q112852839 |
|