Acid-Catalyzed Rearrangement of 9-Hydroxyfuranoeremophilanes to Eremophilanlactones 9-Hydroxyfuranoeremophilanes 1-3 are the main components of freshly harvested rhizomes of P. hybridus Ifuranopetasin chemovar, Table, Fig. I ) . They easily and quantitatively rearrange in the presence of traces of a
Säurekatalysierte umlagerung von 1.2-bismethoxycarbonylcyclopropenen
✍ Scribed by Lutz Schrader
- Publisher
- Elsevier Science
- Year
- 1971
- Tongue
- French
- Weight
- 138 KB
- Volume
- 12
- Category
- Article
- ISSN
- 0040-4039
No coin nor oath required. For personal study only.
✦ Synopsis
der Farbenfabrlken Bayer AG, Bei Versuchen, die photolytisch aus den entsprechenden 3H-Pyrazolen ') u a . . entstandenen Cyclopropene $ -2 durch S~ulenchromatographie an Kleselgel mlt Benz01 zu lsolleren, stellten wlr Ilberraschend fest, dalj dlese sich berelts unter den Bedlngungen der Chromatographle in die Lactone der 4-Hydroxy-buten-2-bzw. -penten-2-sguren @,a -$) umlagern. Wnnschlchtchromatographlsche sowle NMR-spektroskoplsche Untersuchungen der Reaktionsgemische zeigen, da13 die Umlagerung i -+ 2 praktlsch quantitativ verlluft.
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