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Remarkable stereoselectivity in the alkylation of a hydroazulenone: progress towards the total synthesis of guanacastepene

โœ Scribed by Gregory B Dudley; Derek S Tan; Guncheol Kim; Joseph M Tanski; Samuel J Danishefsky

Publisher
Elsevier Science
Year
2001
Tongue
French
Weight
68 KB
Volume
42
Category
Article
ISSN
0040-4039

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โœฆ Synopsis

exo-Methylene ketone 6 serves as a vehicle for elaboration of the C8 quaternary center en route to guanacastepene via a conjugate addition-alkylation sequence. Methylation of the cycloheptadienolate derived from 7 is highly selective for the desired relative stereochemistry, as determined by NMR and crystallographic analysis.

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