title: C-F Activation in Perfluorinated Arenes with Isonitriles under UV-Light Irradiation.
abstract: Due to the great value of fluorinated arenes in agrochemistry, medicinal chemistry and materials science, development of methods for preparation of fluorinated arenes is of high importance. They can be either accessed by arene fluorination or by partial arene defluorination. However, the carbon-fluorine bond belongs to the strongest σ-bonds, which renders C-F activation highly challenging. Here it is shown that aryl and alkyl isonitriles efficiently activate the strong C-F bond in perfluoroarenes by simple UV irradiation under mild conditions. Reactions proceed by formal direct insertion of the isonitrile into the C-F bond without any transition metal. Activation occurs at arene C-F bonds whereas aliphatic C-F bonds remain unreacted. For selected perfluoroarenes C-F activation occurs with high regioselectivity and resulting imidoyl fluorides are transformed into other valuable compounds. Theoretical studies give insights into the reaction mechanism.
authors.affiliation: Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149 Münster (Germany).
authors.forename: Abhishek
authors.initials: A
authors.lastname: Dewanji
authors.affiliation: Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149 Münster (Germany).
authors.forename: Christian
authors.initials: C
authors.lastname: Mück-Lichtenfeld
authors.affiliation: Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149 Münster (Germany).
authors.forename: Klaus
authors.initials: K
authors.lastname: Bergander
authors.affiliation: Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149 Münster (Germany).
authors.forename: Constantin G
authors.initials: CG
authors.lastname: Daniliuc
authors.affiliation: Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149 Münster (Germany). studer@uni-muenster.de.
authors.forename: Armido
authors.initials: A
authors.lastname: Studer
keywords: CF activation; fluorine; perfluoroarene; photochemistry; transition-metal free