title: Synthesis of gem-difluoromethylenated polycyclic cage compounds.
abstract: The synthesis of gem-difluoromethylenated polycyclic cage compounds, utilizing PhSCF2SiMe3 as a gem-difluoromethylene building block, is described. The fluoride-catalyzed nucleophilic addition of PhSCF2SiMe3 to both maleic anhydride-cyclopentadiene and maleic anhydride-cyclohexadiene adducts was accomplished with high stereoselectivity to provide the corresponding adducts that were treated with Grignard reagents, followed by acid-catalyzed lactonization to afford the corresponding γ-butyrolactones, each as a single isomer. These γ-butyrolactones underwent intramolecular radical cyclization to give the corresponding tetracyclic cage γ-butyrolactones, which were employed as precursors for the synthesis of gem-difluoromethylenated tetracyclic cage lactols or tetracyclic cage furans, upon treatment with Grignard reagents.
authors.affiliation: Center of Excellence for Innovation in Chemistry (PERCH-CIC) and Department of Chemistry, Faculty of Science, Mahidol University , Rama VI Road, Bangkok 10400, Thailand.
authors.forename: Chonticha
authors.initials: C
authors.lastname: Masusai
authors.forename: Darunee
authors.initials: D
authors.lastname: Soorukram
authors.forename: Chutima
authors.initials: C
authors.lastname: Kuhakarn
authors.forename: Patoomratana
authors.initials: P
authors.lastname: Tuchinda
authors.forename: Chaveng
authors.initials: C
authors.lastname: Pakawatchai
authors.forename: Saowanit
authors.initials: S
authors.lastname: Saithong
authors.forename: Vichai
authors.initials: V
authors.lastname: Reutrakul
authors.forename: Manat
authors.initials: M
authors.lastname: Pohmakotr