title: Copper-Catalyzed (2+1) Annulation of Acetophenones with Maleimides: Direct Synthesis of Cyclopropanes.
abstract: A practical copper-catalyzed direct oxidative cyclopropanation of electron-deficient alkenes with acetophenone derivatives is reported. The dehydrogenative annulation involves a double C-H bond functionalization at the α-position of the ketone using di-tert-butyl peroxide as oxidant. The broad scope of the reaction and excellent functional-group tolerance is demonstrated for the stereoselective synthesis of fused cyclopropanes. The developed transformation revealed an unprecedented reactivity for copper-catalyzed processes.
authors.affiliation: Abteilung Chemische Biologie, Max-Planck-Institut für Molekulare Physiologie, Otto-Hahn-Strasse 11, 44227 Dortmund (Germany).|Fakultät Chemie und Chemische Biologie, Technische Universität Dortmund, Otto-Hahn-Strasse 6, 44227 Dortmund (Germany).
authors.forename: Srimanta
authors.initials: S
authors.lastname: Manna
authors.affiliation: Abteilung Chemische Biologie, Max-Planck-Institut für Molekulare Physiologie, Otto-Hahn-Strasse 11, 44227 Dortmund (Germany). andrey.antonchick@mpi-dortmund.mpg.de.|Fakultät Chemie und Chemische Biologie, Technische Universität Dortmund, Otto-Hahn-Strasse 6, 44227 Dortmund (Germany). andrey.antonchick@mpi-dortmund.mpg.de.
authors.forename: Andrey P
authors.initials: AP
authors.lastname: Antonchick
keywords: annulation; copper; heterocycles; small-ring compounds; synthetic methods