title: Enantiospecific synthesis of the cubitane skeleton.
abstract: The fully substituted 12-membered macrocycle of the cubitane-type diterpenoids has been assembled in an enantioselective manner following a novel "bridge-and-cut" strategy. Hydroxyalkylation of (S)-carvone afforded a carvonylgeraniol, which underwent transannular cyclization on treatment with samarium diiodide in THF. Fragmentation of one of the shorter bridges of the resulting [8.2.2]bicycle liberated the 12-membered ring with the desired cis-arrangement of the isopropenyl side chains.
authors.affiliation: TU Braunschweig, Institutes of Organic, Inorganic and Analytical Chemistry, Hagenring 30, 38106 Braunschweig, Germany.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Schöttner
authors.forename: Maren
authors.initials: M
authors.lastname: Wiechoczek
authors.forename: Peter G
authors.initials: PG
authors.lastname: Jones
authors.forename: Thomas
authors.initials: T
authors.lastname: Lindel
mesh_terms: D002384:Catalysis; D003500:Cyclization; D004224:Diterpenes / Q000138:chemical synthesis* / Q000737:chemistry*; D015394:Molecular Structure; D013237:Stereoisomerism
chemical_list: D004224:Diterpenes