Magnesiate Addition/Ring-Expansion Strategy To Access the 6–7–6 Tricyclic Core of Hetisine-Type C20-Diterpenoid Alkaloids
2017
A synthetic strategy to access the fused 6–7–6 tricyclic core of hetisine-type C20-diterpenoid alkaloids is reported. This strategy employs a Diels–Alder cycloaddition to assemble a fused bicyclic anhydride intermediate, which is elaborated to a vinyl lactone-acetal bearing an aromatic ring in five steps. Aromatic iodination is followed by magnesium–halogen exchange with a trialkyl magnesiate species, which undergoes intramolecular cyclization. Subsequent oxidation provides the desired 6–7–6 tricyclic diketoaldehyde, with carbonyl groups at all three positions for eventual C–N bond formation and subsequent elaboration.
Keywords:
- Correction
- Source
- Cite
- Save
- Machine Reading By IdeaReader
26
References
5
Citations
NaN
KQI