title: Divergent Reactivity of Thioalkynes in Lewis Acid Catalyzed Annulations with Donor-Acceptor Cyclopropanes.
abstract: Efficient methods for the convergent synthesis of (poly)cyclic scaffolds are urgently needed in synthetic and medicinal chemistry. Herein, we describe new annulation reactions of thioalkynes with phthalimide-substituted donor-acceptor cyclopropanes, which gave access to highly substituted cyclopentenes and polycyclic ring systems. With silyl-thioalkynes, the Lewis acid catalyzed [3+2] annulation reaction with donor-acceptor cyclopropanes took place to afford 1-thio-cyclopenten-3-amines. On the other hand, an unprecedented polycyclic compound was formed with alkyl-thioalkynes through a reaction pathway directly involving the phthalimide group. The two transformations proceeded in good yields and tolerated a large variety of functional groups.
authors.affiliation: Laboratory of Catalysis and Organic Synthesis, Ecole Polytechnique Fédérale de Lausanne, EPFL SB ISIC LCSO, BCH 4306, 1015, Lausanne, Switzerland.
authors.forename: Sophie
authors.initials: S
authors.lastname: Racine
authors.affiliation: Laboratory of Catalysis and Organic Synthesis, Ecole Polytechnique Fédérale de Lausanne, EPFL SB ISIC LCSO, BCH 4306, 1015, Lausanne, Switzerland.
authors.forename: Bence
authors.initials: B
authors.lastname: Hegedüs
authors.affiliation: Laboratory of Catalysis and Organic Synthesis, Ecole Polytechnique Fédérale de Lausanne, EPFL SB ISIC LCSO, BCH 4306, 1015, Lausanne, Switzerland.
authors.forename: Rosario
authors.initials: R
authors.lastname: Scopelliti
authors.affiliation: Laboratory of Catalysis and Organic Synthesis, Ecole Polytechnique Fédérale de Lausanne, EPFL SB ISIC LCSO, BCH 4306, 1015, Lausanne, Switzerland. jerome.waser@epfl.ch.
authors.forename: Jérôme
authors.identifier: http://orcid.org/0000-0002-4570-914X
authors.initials: J
authors.lastname: Waser
keywords: Lewis acids; alkynes; annulation; donor-acceptor cyclopropanes; polycycles