| Autor: |
Spivey AC; Department of Chemistry, Imperial College, London SW7 2AY, UK. a.c.spivey@imperial.ac.uk, Laraia L, Bayly AR, Rzepa HS, White AJ |
| Jazyk: |
angličtina |
| Zdroj: |
Organic letters [Org Lett] 2010 Mar 05; Vol. 12 (5), pp. 900-3. |
| DOI: |
10.1021/ol9024259 |
| Abstrakt: |
SnBr(4)-promoted oxonium-Prins cyclizations to form 2,3-disubstituted tetrahydrofurans (THFs) are reported. In the absence of an internal nucleophile, the carbocation intermediates are trapped by bromide to give 2,3-cis- and 2,3-trans-configured products; two variations with intramolecular trapping are also reported. One of these allows a single-step stereocontrolled synthesis of the core 2,3-cis-THF ring system of cordigol, a fungicidal polyphenol from the stem bark of Cordia goetzei. For this latter transformation, a stepwise oxonium-Prins/cation trapping pathway rather than orthoquinonemethide formation/hetero-Diels-Alder cycloaddition is supported computationally. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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