title: Versatile route to centro-substituted triquinacene derivatives: synthesis of 10-phenyltriquinacene.
abstract: [reaction: see text] A versatile route to prepare centro-substituted triquinacene derivatives (1, R = various substituents), as exemplified by the preparation of 10-phenyltriquinacene (1, R = Ph), is reported. The quaternary, centro substituent (C-10) was installed by a trimethylsilyl chloride-promoted conjugate addition reaction of an organocuprate, derived from phenylmagnesium bromide, and the protected bicyclic enone (11). The resultant trimethylsilyl enol ether was then converted regioselectively to the C-2-allylated conjugate addition products (13, R = Ph). The allyl moiety, following oxidative cleavage of the carbon-carbon double bond, was used to elaborate the tricyclic ring system by an intramolecular aldol/acetal deprotection reaction. The product of this reaction was then converted to the target compound using a standard series of functional group transformation reactions.
authors.affiliation: Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby, British Columbia V5A 1S6, Canada.
authors.forename: Jay A
authors.initials: JA
authors.lastname: Cadieux
authors.forename: Donovan J
authors.initials: DJ
authors.lastname: Buller
authors.forename: Peter D
authors.initials: PD
authors.lastname: Wilson