title: [1+1+1] Cyclotrimerization for the Synthesis of Cyclopropanes.
abstract: The synthesis of small rings by functionalization of C(sp(3) )-H bonds remains a great challenge. We report for the first time a copper-catalyzed [1+1+1] cyclotrimerization of acetophenone derivatives under mild reaction conditions. The reaction has a broad scope for the stereoselective synthesis of cyclopropanes by trimerization of acetophenone. The developed transformation is based on an extraordinary copper-catalyzed cascade process that allows saturated carbocycles to be obtained for the first time by cyclotrimerization through functionalization of C(sp(3) )-H bonds. The cascade of sixfold C(sp(3) )-H bond functionalization allows the synthesis of cyclopropanes in a highly stereoselective approach.
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 4a, 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 4a, 44227, Dortmund, Germany. andrey.antonchick@mpi-dortmund.mpg.de.
authors.forename: Andrey P
authors.initials: AP
authors.lastname: Antonchick
keywords: copper; cyclopropanes; cyclotrimerization; oxidative coupling; radicals