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dc.contributor.advisor Stevens, Robert V.
dc.creatorMaehlum, Ellen Viggen
dc.date.accessioned 2016-04-21T12:01:30Z
dc.date.available 2016-04-21T12:01:30Z
dc.date.issued 1968
dc.identifier.citation Maehlum, Ellen Viggen. "Phenolate radical coupling as a method of triterpene synthesis." (1968) Master’s Thesis, Rice University. https://hdl.handle.net/1911/89113.
dc.identifier.urihttps://hdl.handle.net/1911/89113
dc.description.abstract The dienone [B] is a possible precursor for the synthesis of tetra- and pentacyclic triterpenes. In this investigation a synthesis of the dimeric phenol [A] and the conversion of [A] to [B] by a phenolate radical coupling reaction is presented. The intermediate 5-hydroxy-o-toluic acid is prepared in two ways. The best method consists of heating 2-naphthol-6, 8-disulfonic acid dipotassium salt with sodium hydroxide in an autoclave. In the other method, o-xylene is treated with chlorosulfonic acid, and the resultant sulfonylchloride exposed to ammonium carbonate to yield the corresponding sulfonamide. Oxidation of the sulfonamide with potassium permanganate gives o-toluic acid-5-sulfonamide, which is fused with potassium hydroxide to yield 5-hydroxyotoluic acid. After protecting the phenol group, esterification and subsequent reduction with lithium aluminum hydride gives 2-methyl-5-methoxybenzyl alcohol. This alcohol is treated with phosphorus tribromide yielding the corresponding bromide which reacts with magnesium in the presence of ferric chloride to give a dimeric ether. The ether is finally converted to the dimeric phenol [A]. Several different oxidizing agents are tried to transfer the phenol [A] to the dienone [B]. No useful method is found for preparative work, but the dienone is obtained in poor yield by oxidation with manganese dioxide.
dc.format.extent 65 pp
dc.language.iso eng
dc.title Phenolate radical coupling as a method of triterpene synthesis
dc.type Thesis
dc.identifier.digital RICE0150
dc.type.material Text
thesis.degree.department Chemistry
thesis.degree.discipline Natural Sciences
thesis.degree.grantor Rice University
thesis.degree.level Masters
thesis.degree.name Master of Arts
dc.format.digitalOrigin reformatted digital
dc.identifier.callno Thesis Chem. 1968 Maehlum


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