Ingenane system

Scheme 8.48 Construction of the ingenane ABCD ring system.

Rigby, J. H., Bazin, B., Meyer, J. H., Mohammadi, E. Synthetic Studies on the Ingenane Diterpenes. An Improved Entry into a trans-Intrabridgehead System. Org. Lett. 2002,4, 799-801. 

Bicyclic 2-vinylcyclopropyllithium substrates allow tricyclic systems containing a cyclohepladi-ene moiety to be constructed. Thus, dienone 64, containing the backbone of the tigliane, daphnane. and ingenane families of natural products, can be prepared from 61 by the reaction sequence shown868. 

SCHEME 19.44 Synthesis of the BC ring system of ingenane diteipenes. 

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