Studies on nucleoside H-phosphonoselenoate chemistry and chalcogen exchange reaction between P(V) and P(III) compounds
2005 (English)Doctoral thesis, comprehensive summary (Other academic)
In this thesis, the chemistry of compounds containing P-Se bonds has been studied. As a new addition to this class of compounds, H-phosphonoselenoate monoesters, have been introduced and two synthetic pathways for their preparation have been developed.
The reactivity of H-phosphonoselenoate monoesters towards a variety of condensing agents has been studied. From these, efficient conditions for the synthesis of H-phosphonoselenoate diesters have been developed. The produced diesters have subsequently been used in oxidative transformations, which gave access to the corresponding P(V) compounds, e.g. dinucleoside phosphoroselenoates or dinucleoside phosphoroselenothioates.
Furthermore, a new selenizing agent, triphenyl phosphoroselenoate, has been developed for selenization of P(III) compounds. This reagent has high solubility in organic solvents and was found to convert phosphite triesters and H-phosphonate diesters efficiently into the corresponding phosphoroselenoate derivatives.
The selenization of P(III) compounds with triphenyl phosphoroselenoate proceeds through a selenium transfer reaction. A computational study was performed to gain insight into a mechanism for this reaction. The results indicate that the transfer of selenium or sulfur from P(V) to P(III) compounds proceeds most likely via an X-philic attack of the P(III) nucleophile on the chalcogen of the P(V) species. For the transfer of oxygen, the reaction may also proceed via an edge attack on the P=O bond.
Place, publisher, year, edition, pages
Stockholm: Institutionen för organisk kemi , 2005. , 38 p.
Phosphorus chemistry, H-phosphonate, H-phosphonoselenoate, nucleotide analogues, selenization, selenium transfer, phosphoroselenoate
IdentifiersURN: urn:nbn:se:su:diva-736ISBN: 91-7155-163-8OAI: oai:DiVA.org:su-736DiVA: diva2:198120
2005-12-02, Magnélisalen, Kemiska övningslaboratoriet, Svante Arrhenius väg 12 A, Stockholm, 14:00
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