✦ LIBER ✦
Allo-, Epiallo- und Pseudoyohimbane sowie Heteroyohimbane durch Reaktion eines tetracyclischen Aldehyds mit Acetessigester in verschiedenen Lösungsmitteln
✍ Scribed by Rosenmund, Peter ;Casutt, Michael ;Wittich, Michael
- Book ID
- 102902257
- Publisher
- John Wiley and Sons
- Year
- 1990
- Tongue
- English
- Weight
- 671 KB
- Volume
- 1990
- Category
- Article
- ISSN
- 0947-3440
No coin nor oath required. For personal study only.
✦ Synopsis
Allo‐, Epiallo‐, and Pseudoyohimbanes as well as Heteroyohimbanes by Reaction of a Tetracyclic Aldehyde with Acetoacetate in Different Solvents
The reaction of methyl acetoacetate with 4 in CH~3~OH/ CH~3~ONa leads to 11 and 12 with yohimbane skeleton but bicyclo ring E. In DMF/__t__BuOK, the epialloheteroyohimbane 13 is produced in fairly good yield, whereas in THF/NaH the allo‐19‐hydroxyyohimbinone 17 is formed, which undergoes thermal decomposition to the alloyohimb‐18‐enone 19. Finally, a full description of an early mentioned synthesis of rac‐de‐plancheine (7) is given.