title: A [2+2+2]-Cyclotrimerization Approach to Selectively Substituted Fluorenes and Fluorenols, and Their Conversion to 9,9'-Spirobifluorenes.
abstract: Synthesis of selectively substituted fluorenes and fluorenols was achieved by using catalytic [2+2+2]cyclotrimerization. Various starting diynes were reacted with different alkynes in the presence of a catalytic amount of Wilkinson's catalyst (RhCl(PPh3)3) providing the compounds possessing the fluorene scaffold in good isolated yields. A set of four regioselectively substituted fluorenols was converted to the corresponding 9,9'-spirobifluorenes and their spectral characteristics were measured.
authors.affiliation: Department of Organic Chemistry, Faculty of Science, Charles University in Prague, Albertov 6, 128 43 Praha 2 (Czech Republic).
authors.forename: Reinhard P
authors.initials: RP
authors.lastname: Kaiser
authors.affiliation: Department of Organic Chemistry, Faculty of Science, Charles University in Prague, Albertov 6, 128 43 Praha 2 (Czech Republic).
authors.forename: Filip
authors.initials: F
authors.lastname: Hessler
authors.affiliation: Department of Inorganic Chemistry, Faculty of Science, Charles University in Prague, Albertov 6, 128 43 Praha 2 (Czech Republic).
authors.forename: Jiří
authors.initials: J
authors.lastname: Mosinger
authors.affiliation: Department of Inorganic Chemistry, Faculty of Science, Charles University in Prague, Albertov 6, 128 43 Praha 2 (Czech Republic).
authors.forename: Ivana
authors.initials: I
authors.lastname: Císařová
authors.affiliation: Department of Organic Chemistry, Faculty of Science, Charles University in Prague, Albertov 6, 128 43 Praha 2 (Czech Republic). kotora@natur.cuni.cz.
authors.forename: Martin
authors.initials: M
authors.lastname: Kotora
keywords: aromatic compounds; catalysis; cycloaddition; rhodium; spiro compounds