title: Low-Pressure Cobalt-Catalyzed Enantioselective Hydrovinylation of Vinylarenes.
abstract: An efficient and practical protocol for the enantioselective cobalt-catalyzed hydrovinylation of vinylarenes with ethylene at low (1.2 bar) pressure has been developed. As precatalysts, stable [L2 CoCl2 ] complexes are employed that are activated in situ with Et2 AlCl. A modular chiral TADDOL-derived phosphine-phosphite ligand was identified that allows the conversion of a broad spectrum of substrates, including heterocyclic vinylarenes and vinylferrocene, to smoothly afford the branched products with up to 99 % ee and virtually complete regioselectivity. Even polar functional groups, such as OH, NH2 , CN, and CO2 R, are tolerated.
authors.affiliation: Department of Chemistry, University of Cologne, Greinstrasse 4, 50939, Cologne, Germany.
authors.forename: Sohajl
authors.initials: S
authors.lastname: Movahhed
authors.affiliation: Department of Chemistry, University of Cologne, Greinstrasse 4, 50939, Cologne, Germany.
authors.forename: Julia
authors.initials: J
authors.lastname: Westphal
authors.affiliation: Department of Chemistry, University of Cologne, Greinstrasse 4, 50939, Cologne, Germany.
authors.forename: Mehmet
authors.initials: M
authors.lastname: Dindaroğlu
authors.affiliation: Department of Chemistry, University of Cologne, Greinstrasse 4, 50939, Cologne, Germany.
authors.forename: Anna
authors.identifier: http://orcid.org/0000-0003-1634-8610
authors.initials: A
authors.lastname: Falk
authors.affiliation: Department of Chemistry, University of Cologne, Greinstrasse 4, 50939, Cologne, Germany. Schmalz@uni-koeln.de.
authors.forename: Hans-Günther
authors.initials: HG
authors.lastname: Schmalz
keywords: C−C bond formation; alkenes; asymmetric catalysis; chirality; cobalt