| Autor: |
Leber PA; Department of Chemistry, Franklin & Marshall College, Lancaster, Pennsylvania 17604-3003, USA. phyllis.leber@fandm.edu, Lasota CC, Strotman NA, Yen GS |
| Jazyk: |
angličtina |
| Zdroj: |
The Journal of organic chemistry [J Org Chem] 2007 Feb 02; Vol. 72 (3), pp. 912-9. |
| DOI: |
10.1021/jo0621017 |
| Abstrakt: |
Over the temperature range 250-300 degrees C, 8-exo-methoxybicyclo[4.2.0]oct-2-ene (1a) undergoes a [1,3] sigmatropic rearrangement to 5-exo- and 5-endo-methoxybicyclo[2.2.2]oct-2-enes, 2a and 2b, respectively, with a clear preference for the si product: si/sr = 3.2. Both 1a and its 8-endo epimer 1b experience appreciable epimerization and fragmentation. A long-lived intermediate with weakly interacting diradical centers, one of which is stabilized by a methoxy substituent, can account for all such observations. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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